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U.S. Department of the Interior U.S. Geological Survey Open-File Report 2018–1180 Prepared in cooperation with the National Park Service Optimizing Historical Preservation Under Climate Change— An Overview of the Optimal Preservation Model and Pilot Testing at Cape Lookout National Seashore
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U.S. Department of the InteriorU.S. Geological Survey

Open-File Report 2018–1180

Prepared in cooperation with the National Park Service

Optimizing Historical Preservation Under Climate Change—An Overview of the Optimal Preservation Model and Pilot Testing at Cape Lookout National Seashore

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Front Cover. Portsmouth Life-Saving Station (circa 1894) in Portsmouth Village (photograph credit: Erin Seekamp, 2015)

Back Cover. 1873 Keeper’s Quarters (circa 1873) and Cape Lookout Lighthouse (circa 1812; 1859) within the Light Station Complex of Cape Lookout Village, taken from the Atlantic Ocean dunes (photograph credit: Erin Seekamp, 2015)

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Optimizing Historical Preservation Under Climate Change—An Overview of the Optimal Preservation Model and Pilot Testing at Cape Lookout National Seashore

By Erin Seekamp, Max Post van der Burg, Sandra Fatorić, Mitchell J. Eaton, Xiao Xiao, and Allie McCreary

Prepared in cooperation with the National Park Service

Open-File Report 2018–1180

U.S. Department of the InteriorU.S. Geological Survey

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U.S. Department of the InteriorDAVID BERNHARDT, Acting Secretary

U.S. Geological SurveyJames F. Reilly II, Director

U.S. Geological Survey, Reston, Virginia: 2019

For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit https://www.usgs.gov or call 1–888–ASK–USGS.

For an overview of USGS information products, including maps, imagery, and publications, visit https://store.usgs.gov.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.

Suggested citation:Seekamp, E., Post van der Burg, M., Fatorić, S., Eaton, M.J., Xiao, X., and McCreary, A., 2019, Optimizing historical preservation under climate change—An overview of the optimal preservation model and pilot testing at Cape Lookout National Seashore: U.S. Geological Survey Open-File Report 2018–1180, 46 p., https://doi.org/10.3133/ofr20181180.

ISSN 2331-1258 (online)

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Acknowledgments

The authors would like to thank all the individuals who participated in the workshops, meetings, and online elicitation exercises. We are particularly appreciative of the time, creative energy, and support provided by specific National Park Service personnel: Pat Kenney, former Cape Lookout National Seashore Park Superintendent; Jeri DeYoung, former Cape Lookout National Seashore Chief of Resources; Curtis Rintz, former Cape Lookout National Seashore Exhibits Specialist; Janet Cakir, Southeast Region Climate Change, Socioeconomics, and Adaptation Coordinator; Cat Hoffman-Hawkins, Climate Response Program Chief; Marcy Rockman, former Climate Change Adaptation Coordinator for Cultural Resources; and Brian Goeken, Technical Preservation Services Chief. We are also particularly appreciative of the time, creative energy, and support provided by the North Carolina State Historic Preservation Office (Ramona Bartos, Deputy State Historic Preservation Officer; and John Wood, Preservation/Restoration Specialist).

This document was developed as part of the Connecting Landscape Adaptation and National Cultural Resource Policy to Climate Change and Cultural Resource Adaptation Decisions research project. The research was supported by the U.S. Geological Survey (https://www.usgs.gov) through the National Climate Change and Wildlife Science Center (https://casc.usgs.gov/) and the Department of Interior Southeast Climate Adaptation Science Center (https://globalchange.ncsu.edu/secsc/) through grant agreement G15AP00141. Additional funding for model development was provided by the National Park Service Climate Change Response Program through U.S. Department of Interior Inter-Agency Agreement P17PG00197 (project title: Optimization Model to Support NPS Cultural Resource Management). See also Xiao and others (2019) for more additional model outputs than those reported here.

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ContentsAcknowledgments ........................................................................................................................................iiiAbstract ...........................................................................................................................................................1Introduction.....................................................................................................................................................1Study Area.......................................................................................................................................................2Model Development ......................................................................................................................................3The Optimal Preservation Model ................................................................................................................5Model Results and Interpretations .............................................................................................................8

Scenario 1—No Action ........................................................................................................................8Scenario 2—An Uncertain Budget ....................................................................................................9

Portfolio for a Budget of $50,000 ...............................................................................................9Portfolio for a Budget of $222,000 ...........................................................................................11Portfolio for a Budget of $500,000 ...........................................................................................14

Scenario 3—Accounting For Periodic Funding Increases ..........................................................16Portfolio For A Budget Of $70,000 With A Surge Of $225,000 Every 5 Years .....................16Portfolio For A Budget Of $222,000 With A Surge Of $225,000 Every 5 Years ...................16

Scenario 4—Ignoring Vulnerability .................................................................................................16Portfolio For A Budget Of $222,000 Without Vulnerability ...................................................16

Scenario 5—Excluding The Attributes Of “Use Potential” ..........................................................16Portfolio For A Budget Of $222,000 Without Use Potential .................................................16

Comparing Scenarios ..................................................................................................................................21Insights From The Pilot Study ....................................................................................................................21Considerations For Advancing The Optipres Model ..............................................................................24References Cited..........................................................................................................................................25Appendix 1. Optimal Preservation Model Objectives, Attributes, Weights, Actions, and

Costs .................................................................................................................................................28Appendix 2. Value of Condition, Remaining Significance, and Use Potential for 17 Buildings

Among Different Scenarios ..........................................................................................................37Appendix 3. Computer Code for Optimal Preservation Model ..........................................................46

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Figures

1. Timeline of the structured process used in the pilot study at Cape Lookout National Seashore ........................................................................................................................................5

2. Adaptation actions included in the Optimal Preservation Model ........................................7 3. Optimal Preservation Model dynamics .....................................................................................8 4. Scenario 1: Accumulated resource values ..............................................................................9 5. Scenario 1: Percentages of total resource value for each building ..................................10 6. Scenario 2: Expected total resource value ............................................................................11 7. Scenario 2: Optimal policy under a $50,000 annual budget allocation ..............................12 8. Scenario 2: Proportional value and cost under a $50,000 annual budget .........................12 9. Scenario 2: Optimal policy under a $222,000 annual budget allocation ............................13 10. Scenario 2: Proportional value and cost under a $222,000 annual budget .......................13 11. Scenario 2: Optimal policy under a $500,000 annual budget allocation ............................15 12. Scenario 2: Proportional value and cost under a $500,000 annual budget .......................15 13. Scenario 3: Optimal policy under a $70,000 annual budget allocation with surges

of $225,000 every 5 years ...........................................................................................................17 14. Scenario 3: Proportional value and cost under a $70,000 annual budget with

surges of $225,000 every 5 years ..............................................................................................17 15. Scenario 3: Optimal policy under a $222,000 annual budget allocation with surges

of $225,000 every 5 years ...........................................................................................................18 16. Scenario 3: Proportional value and cost under a $222,000 annual budget with

surges of $225,000 every 5 years ..............................................................................................18 17. Scenario 4: Optimal policy under a $222,000 annual budget allocation without

consideration of vulnerability ...................................................................................................19 18. Scenario 4: Proportional value and cost under a $222,000 annual budget without

consideration of vulnerability ...................................................................................................19 19. Scenario 5: Optimal policy under a $222,000 annual budget allocation without

consideration of use potential ..................................................................................................20 20. Scenario 5: Proportional value and cost under a $222,000 annual budget allocation

without consideration of use potential ...................................................................................20 21. Accumulated value and total cost of all buildings for all budget scenarios ....................22 22. Comparison of allocated budget versus actual expenditures for all budget

scenarios ......................................................................................................................................23

Appendix Figures

2.1–2.7. Components of resource value under annual allocation of— 2.1. $50,000 ..........................................................................................................................................38 2.2. $222,000 ........................................................................................................................................39 2.3. $500,000 ........................................................................................................................................40 2.4. $70,000 with an additional $225,000 every 5 years ................................................................41 2.5. $222,000 with an additional $225,000 every 5 years ..............................................................42 2.6. $222,000 assuming no vulnerability ..........................................................................................43 2.7. $222,000 assuming no use potential ........................................................................................44 2.8. Accumulated values and total costs of individual buildings under each scenario .........45

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Table

1. Details of 17 buildings selected for pilot study ........................................................................4

Appendix Tables

1.1. Historical significance’s attributes, subattributes, and metrics with scores including weights among the attributes and subattributes .................................................29

1.2. Use potential’s attributes and metrics with scores including weights among the attributes ......................................................................................................................................30

1.3. Use potential’s attributes and metrics with scores including weights among the attributes. Exposure’s subattributes and corresponding data sources ............................31

1.4. Sensitivity’s subattributes and corresponding data sources ..............................................311.5. Vulnerability’s metrics and scores ...........................................................................................311.6. Optimal Preservation Model adaptation actions and model dynamics .............................321.7. Adaptation actions and maintenance costs for each of the 17 historic buildings ..........36

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Optimizing Historical Preservation Under Climate Change—An Overview of the Optimal Preservation Model and Pilot Testing at Cape Lookout National Seashore

By Erin Seekamp,1 Max Post van der Burg,2 Sandra Fatorić,1 Mitchell J. Eaton,2 Xiao Xiao,1 and Allie McCreary1

1Department of Parks, Recreation and Tourism Management, College of Natural Resources, North Carolina State University.

2U.S. Geological Survey.

AbstractAdapting cultural resources to climate-change effects

challenges traditional cultural resource decision making because some adaptation strategies can negatively affect the integrity of cultural resources. Yet, the inevitability of climate-change effects—even given the uncertain timing of those effects—necessitates that managers begin prioritiz-ing resources for climate-change adaptation. Prioritization imposes an additional management challenge: managers must make difficult tradeoffs to achieve desired management out-comes related to maximizing the resource values. This report provides an overview of a pilot effort to integrate vulnerabil-ity (exposure and sensitivity), significance, and use potential metrics in a decision framework—the Optimal Preservation (OptiPres) Model—to inform climate adaptation planning of a subset of buildings in historic districts (listed on the National Register of Historic Places) at Cape Lookout National Sea-shore. The OptiPres Model uses a numerical optimization algorithm to assess the timing and application of a portfolio of adaptation actions that could most effectively preserve an assortment of buildings associated with different histories, intended uses, and construction design and materials over a 30-year planning horizon. The outputs from the different bud-get scenarios, though not prescriptive, provide visualizationsof and insights to the sequence and type of optimal actions andthe changes to individual building resource values and accu-mulated resource values. Study findings suggest the OptiPresModel has planning utility related to fiscal efficiency by identi-fying a budget threshold necessary to maintain the historicalsignificance and use potential of historical buildings whilereducing vulnerability (collectively, the accumulated resourcevalue). Specifically, findings identify that a minimum of theindustry standard ($222,000 annually for the 17 buildings) isneeded to maintain the current accumulated resource value.Additionally, results suggest that additional appropriationsprovided on regular intervals when annual appropriations are

at the industry standard are nearly as efficient as annual appro-priations at twice the rate of industry standards and increase the amount of accumulated resource values to nearly the same level. However, periodic increases in funding may increase the risks posed to buildings from the probability of a natural hazard (that is, damage or loss from a hurricane). Suggestions for model refinements include developing standardized cost estimations for adaptation actions based on square footage and building materials, developing metrics to quantify the historical integrity of buildings, integrating social values data, including additional objectives (such as public safety) in the model, refining vulnerability data and transforming the data to include risk assessment, and incorporating stochastic events (that is, hurricane and wind effects) into the model.

IntroductionCultural resources include physical and intangible aspects

of what is significant about our heritage, having important historical, cultural, scientific, or technological associations that provide societal meanings (National Park Service [NPS], 1995). The U.S. Department of the Interior NPS is mandated “to identify, protect, and share the cultural resources under its jurisdiction” (NPS, 1998, p. 5), and decision making is predicated on recognizing variations in meaning, integrity (that is, “retains material attributes associated with its social values”), and threats (NPS, 1995, p. 11). One threat that is of concern to the NPS is climate change because changing temperatures, changing precipitation patterns, and rising seas increase the exposure of cultural resources to typical decay patterns and rates, and deferred maintenance and repair make them more sensitive to climate change (Rockman and oth-ers, 2016). Natural hazards, such as hurricanes and nor’easter storms, also increase the exposure of cultural resources in the near term. Moreover, the uncertainties of the timing and sever-ity of climate change-related effects complicate managers’

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2 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

ability to enhance the resilience of physical cultural resources, particularly when managers must simultaneously consider an assortment of vulnerable resources. The purpose of this study was to develop and test a decision model framework, the Optimal Preservation (OptiPres) Model, to integrate multiple considerations (including budget constraints, cultural resource vulnerabilities to climate-change effects, cultural resource conditions, heritage values, and the use potential of cultural resources) to inform planning decisions for adapting cultural resources to climate change.

Adapting cultural resources to climate-change effects challenges traditional cultural resource decision making because some adaptation strategies can negatively affect the integrity of cultural resources, and the timing of many climate-change effects are uncertain. In other words, effects to social values and the uncertainties of climate change increase the complexity of adaptation because managers may need to apply actions that tradeoff potential or uncertain future effects against more near-term maintenance of cultural resources. Such challenges increase the complexity of long-term plan-ning, particularly when cultural resources exist in dynamic landscapes like coastal systems where stochastic storms occur. Additionally, the lack of sufficient financial resources to adequately manage all cultural resources—as evidenced by the backlog of deferred maintenance—necessitates that decision makers must consider prioritizing some resources over others. Prioritization imposes an additional management challenge: managers must make difficult tradeoffs to achieve desired management outcomes related to maximizing the resource values (for example, significance, integrity, and use poten-tial) within cultural landscapes. Yet, when approached with a systematic process for addressing such complex decisions, a management agency can enhance the transparency of values embedded within planning and decision making and increase its ability to preserve cultural resource values for present and future generations.

Current policy guidance (NPS, 2014) for the stewardship of cultural resources in relation to climate change states that management decisions should be directed toward resources that are “both significant and most at risk.” The NPS has since implemented a process for assessing climate change vulner-ability of coastal park assets, which includes facilities, infra-structure, and cultural resources (NPS, 2016; Peek and others, 2017). Additionally, Fatorić and Seekamp (2017a, 2018) developed a framework for measuring the significance and use potential of one specific type of cultural resource: historic buildings. This report provides an overview of a pilot effort to integrate vulnerability (exposure and sensitivity), significance, and use potential metrics in a decision framework to inform climate adaptation planning of a subset of buildings in historic districts (listed on the National Register of Historic Places) at Cape Lookout National Seashore, North Carolina.

The decision framework, the OptiPres Model, developed and piloted at Cape Lookout National Seashore is an innova-tive approach for climate adaptation planning of an assortment of resources, advancing single-resource planning approaches

described in the NPS’s Cultural Resources Climate Change Strategy (Rockman and others, 2016) and the Interagency Climate-Smart Conservation (Stein and others, 2014) guid-ance document. More specifically, the OptiPres Model uses numerical optimization methods (that is, an algorithm) to assess the timing and application of a portfolio of adaptation actions that could most effectively preserve an assortment of buildings associated with different histories, intended uses, and construction design and materials over a 30-year planning horizon. Such optimization approaches are widely used in landscape planning. For example, Westphal and others (2007) used an optimization model to identify sites for landscape reconstruction to maximize the number of bird species in the Mount Lofty Ranges, South Australia.

The modeling effort described in this report is the cul-mination of the structured decision-making (SDM) process implemented at Cape Lookout National Seashore that began with Fatorić and Seekamp’s (2017b, 2018) measurement framework, a project funded by the U.S. Department of the Interior Southeast Climate Science Center. It is our intention that the OptiPres Model outputs can enhance NPS managers’ ability to make more informed and transparent climate adapta-tion decisions given various uncertainties and management constraints. Yet, it is important to note that the OptiPres Model is not intended to be prescriptive. Rather, it should be used as one of several information sources (for example, stakeholder studies) for guiding climate adaptation planning and manage-ment. Additional model outputs, with slight modifications to the algorithm, can be found in Xiao and others (2019).

It also is important to note that the cultural resources addressed in the decision framework are physical historic assets (buildings). Although intangible cultural resources (for example, community practices and knowledge) are impor-tant considerations for adaptation planning, they are not addressed in this study. Additional research is needed that specifically addresses how to integrate intangible resources into climate adaptation planning. For example, see Henderson and Seekamp (2018) for a community engagement study that provides a first step towards developing an approach for cli-mate adaptation planning of intangible cultural resources.

Study AreaCape Lookout National Seashore is located on a 56-mile

long chain of barrier islands (about 29,000 acres) on the coast of North Carolina. The barrier islands are subject to coastal dynamics that change the location of sands, tidal marshes and flats, and inlets; historical records document the effects of storm-related flooding and erosion on the islands’ evolution and migration over the past two centuries (Riggs and Ames, 2007). The park unit has two settlements that have been des-ignated on the National Register of Historic Places (NRHP) as historic districts: (1) Portsmouth Village (designated in 1976) and (2) Cape Lookout Village (designated in 2000). Most

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Model Development 3

buildings in these villages experience periodic but recurring flooding after storms. Portsmouth Village has a traditional village feeling, with community buildings (church, post office and general store, and school) and private residences, as well as a former Life-Saving Service station. Although Cape Lookout Village also has ties to Federal maritime history (that is, the Cape Lookout Light Station Complex was listed on the NRHP in 1972, and the Cape Lookout Coast Guard Station Complex was listed on the NRHP in 1988), and some former residences are linked to this history, the 14 residential build-ings (one of which is a former Life-Saving Service station) are not arranged as a traditional village but rather as separate vacation and secondary homes or seasonal fishing camps.

Although Cape Lookout National Seashore has archeo-logical sites, cemeteries, and cultural artifacts associated with World War II military installments, we restricted our pilot study to a subset of historic buildings (n=17), predominately pre-World War II, to test the OptiPres Model before invest-ing further into its development. With the guidance of park managers, we selected the buildings to represent a range of historic periods and occupational uses. During the selection discussions with the park superintendent and the park chief of resources, we sought variability in the current physical condition of buildings and vulnerability (that is, exposure and sensitivity) to climate-change effects (table 1). This initial assessment of exposure and sensitivity (that is, vulnerability) was based on park managers’ knowledge of prior flooding and storm-related damage. It is important to note that few buildings at Cape Lookout National Seashore were of low or moderate vulnerability, which was confirmed by the vulner-ability assessment by Peek and others (2017).

Model DevelopmentThe development of the OptiPres Model represents a

continuation of a SDM process described by Fatorić and Seekamp (2017b). SDM is rooted in decision analysis and behavioral decision theory (Gregory and others, 2011; Runge and others, 2013) and is considered a transparent and col-laborative approach for supporting informed and defensible decisions (Irwin and others, 2011). The SDM process breaks complex decisions into six primary components that can be addressed individually and then reintegrated to identify a solution: (1) problem—defining a clear problem statement; (2) objectives—identifying participants’ values and translating these into measurable objectives; (3) alternatives—specifying a set of available actions that are viewed as possible alterna-tives for achieving defined objectives; (4) consequences—predicting and quantifying the outcomes of alternative actions in terms of stated objectives; (5) tradeoffs—when objectives are in competition, a value-based evaluation of tradeoffs among objectives for any given action is required; and(6) decision—integrating the previous components allows the decision maker to select the action that provides the highest

likelihood of achieving the specified objectives (Runge and others, 2013).

This structured process can facilitate transparency and, hence, legitimacy and buy-in for climate adaptation decisions, particularly in situations with high uncertainty (for example, financial and climate). The advantage of using such a decision process is the explicit valuation of decision makers’ and stake-holders’ preferences and distinguishing these from predictions of the outcomes of implementing a decision (that is, objective science; Gregory and others, 2011; Runge and others, 2013). To the best of our knowledge, this project represents the first application of an SDM process in the context of climate change adaptation for cultural resource preservation.

Because the purpose of this report is to present the OptiPres Model and describe how its outputs may inform climate adaptation planning efforts, we provide an overview of the structured process used that resulted in the OptiPres Model in figure 1. This process included an initial workshop at Cape Lookout National Seashore, followed by iterative meetings with Cape Lookout National Seashore managers and North Carolina State Historic Preservation Office managers and staff, online expert elicitations, and two workshops to expand the expert elicitation to broader audiences at (1) the 2016 George Wright Society annual conference and (2) the National Conference of State Historic Preservation Officers. Additional details on the earlier stages of the process that resulted in the historical significance and use potential attributes and metrics were provided in Fatorić and Seekamp (2017a, 2017b, 2018).

The problem statement that was finalized at the first workshop at Cape Lookout National Seashore (together with its relevant elements shown in parentheses) stated the following: climate change is threating cultural resource preservation at coastal national park units. The NPS (decision maker) wants to develop a transparent and objective deci-sion framework that will help guide their funding allocations (action) toward cultural resource adaptation efforts within Cape Lookout National Seashore that includes two historic districts, Portsmouth and Cape Lookout Villages, and their associated buildings (scope). Although the funding allocation decisions (within budget constraints) for cultural resource maintenance or additional preservation treatments are made annually, the NPS’ vision for managing cultural resources looks forward over the next 30 years (timing) and aims to incorporate fiscal, climate, and environmental uncertainties (uncertainty). Given legal requirements (constraint) and NPS’ mission (trigger), the decision framework would consider the nature and intent of the National Historic Preservation Act and the NPS’ stewardship responsibilities.

The objectives that were refined throughout the process included maintaining historical significance, maximizing the use of historic buildings (hereafter “maximizing use poten-tial”), maximizing financial efficiency, and minimizing climate vulnerability (exposure and sensitivity to sea level rise and storm-related flooding effects) in adapting historic buildings. The first three objectives (maintaining historical signifi-cance, maximizing use potential, and maximizing financial

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4 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Table 1. Details of 17 buildings selected for pilot study.Selection criteria

Historic district Building (circa) Building abbreviation Condition1 Vulnerability2 Use3

Iconic buildings

Cape Lookout Village Cape Lookout Lighthouse (1812; 1859)

Lighthouse Fair Moderate Open to public visitation

Portsmouth Village Methodist Church (1840; 1915)

Church Fair High Open to public visitation

Early Federal maritime history

Cape Lookout Village Cape Lookout Life-Saving Station (1887; 1958)

Lifesaving Station CLV Poor Moderate No use

Portsmouth Village Portsmouth Life-Saving Station (1894)

Lifesaving Station PLV Fair High Open to public visitation

Mid-Federal maritime history

Cape Lookout Village 1873 Keeper's Quarters (1873)

Keeper's Quarters Fair High Open to public visitation and operational use

Cape Lookout Village 1907 Keeper's Quarters (1907; 1958)

1907 Keeper's Quarters Fair Moderate No use

Late maritime history

Cape Lookout Village Jetty Workers House I (1915)

Jetty Workers House 1 Fair High No use

Cape Lookout Village Jetty Workers House II (1920)

Jetty Workers House 2 Poor High No use

Secondary buildings within a complex of buildings

Cape Lookout Village Coast Guard Station Galley (1917)

Galley Fair Low No use

Portsmouth Village Portsmouth Life-Saving Station Summer Kitchen (1894)

Summer Kitchen Good High Operational use

Community buildings

Portsmouth Village Portsmouth Island Schoolhouse (1910)

School Fair High Open to public visitation

Portsmouth Village Portsmouth Island Post Office and General Store (1900)

Post Office Fair High Open to public visitation

Residential buildings

Cape Lookout Village Gordon Willis House (1950)

Gordon Willis House Fair High No use

Cape Lookout Village O'Boyle Bryant House (1938)

O'Boyle Bryant House Poor Moderate No use

Portsmouth Village Washington–Roberts House (1840)

Washington–Roberts House

Good High Open to public visitation

Portsmouth Village Frank Gaskill House (1930) Frank Gaskill House Poor High No usePortsmouth Village Henry Pigott House (1902) Henry Pigott House Good High Open to public

visitation1Condition was determined by using the List of Classified Structures (LCS) condition scores and reviewed by the park superintendent and chief of resources

to confirm or modify current condition status.2Vulnerability was determined by the park superintendent and park chief of resources and confirmed by the vulnerability assessment conducted by Peek and

others (2017).3Visitation and operational use were determined by the park superintendent and chief of resources.

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The Optimal Preservation Model 5

efficiency) are considered fundamental objectives (the ends to be achieved). The fourth objective (minimizing climate vul-nerability) is a means objective (the way in which the funda-mental objectives can be achieved).

Other terminology used in this report include “attribute” (that is, an important and measurable characteristic of an objective that helps define its meaning and value; synonymous with “performance metric”), “metric” (the unit of measure-ment that is applied to each attribute), “score” (the numeric value that represents each level of a metric and the scaled difference between each level of a metric), and “weight” (the importance of each attribute relative to all other attributes).

The Optimal Preservation ModelThe purpose of the OptiPres Model is to provide deci-

sion makers with guidance on how to best manage multiple historic buildings over time. More specifically, the model uses an optimization algorithm to evaluate tradeoffs among (1) investing in actions that maintain or preserve resources in situ, (2) investing in actions that preserve a structure but remove it from its historical context, or (3) making triage deci-sions to free up resources for more costly actions. The model

selects the combination of investments that provides the most resource value to the decision maker over a specified period and budget constraint.

We have provided visual descriptions of optimal invest-ment portfolios (sequences of actions applied to a set of build-ings; hereafter “portfolio” or “portfolios”) to aid with data interpretation. Managers using this model should recognize that the model outputs (that is, visualizations) are not prescrip-tive (that is, do not provide a specific path for implementing adaptation actions) but rather are descriptive (that is, dem-onstrate the patterns of, or strategic approaches for, optimal actions given specific budget constraints) and should be used to inform decision making. In this report, we demonstrate the use of this model assuming the objective is to maximize total resource value (historical significance and use potential) over a 30-year planning horizon.

It is important to note specific limitations related to the use of a 30-year planning horizon. For example, climate change scenarios and land-cover change projections change as forecasting science becomes more fine-tuned, and current models highlight that drastic sea level rise effects may not be actualized in 30 years. Managers may find that inunda-tion will occur at increased or decreased rates compared to the forecasting scenario used in this study (Representative Concentration Pathway [RCP] 8.5), which will enhance or

Figure 1. Timeline of the structured process used in the pilot study at Cape Lookout National Seashore.

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6 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

limit the effectiveness of some adaptation strategies in a 30-year planning horizon.

We developed an objective function, or a numericalexpression of the statement above, which integrates weighted resource value attributes related to historical significance and use potential (for specific details, see Fatorić and Seekamp, 2017a, 2018), and nonweighted vulnerability attributes (that is, exposure and sensitivity data) for flooding-related coastal climate change threats (for specific details, see NPS, 2016; Peek and others, 2017).

The historical significance attributes include the following:

• Association with fundamental purpose of the park unit,

• Condition of the building,

• Historic character (a weighted average of two subat-tributes: defining character and uniqueness to the park),and

• National Register (a weighted average of two subattrib-utes: spatial significance and eligibility).

The use potential attributes include the following:• Operational use,

• Visitor use,

• Interpretive use,

• Third-party use, and

• Scientific use.The exposure attributes include the following:• Flooding exposure (based on Federal Emergency Man-

agement Agency flood maps),

• Storm surge estimates (mean high tide during cat-egory 3 hurricanes),

• Sea level rise projections for 2050 (under a high,RCP 8.5 emission scenario),

• Erosion and coastal proximity, and

• Evidence of historical flooding.The sensitivity attributes include the following:• Flood damage potential,

• Storm resistance,

• Prior storm damage, and

• The presence of protective engineering.The vulnerability attributes include the following:• Exposure and

• Sensitivity.

More details for the historical significance, use poten-tial, exposure, sensitivity, and vulnerability attributes, including metrics and scores, are provided in appendix 1 (tables 1.1–1.5).

Under specific budget allocations, the model searches for optimal combinations of adaptation action applied to each building over a 30-year time horizon. Adaptation actions were developed based on those listed in the NPS Cultural Resource Climate Change Strategy (Rockman and others, 2016). The cost of each action is building-specific, and the total annual cost of these actions must stay under the annual budget cap or constraint. The available adaptation actions (fig. 2) include the following:

• Preservation (core and shell) using historic materials,

• Preservation (core and shell) using resilient materials,

• Elevate,

• Relocate,

• Relocate and elevate,

• Document and monitor, and

• Active removal.It is important to note that “relocate and elevate” was included as one adaptation action for the buildings in Portsmouth Village. The most ideal relocation zones (mapped by proj-ect collaborators in the Program for the Study of Developed Shorelines at Western Carolina University who conducted the Vulnerability Assessment for the NPS) were in an area that experiences periodic standing water after storms (verified by Cape Lookout National Seashore staff), which made relocation as a stand-alone adaptation action unfeasible. Additionally, the relocation zone maps illustrated that there is not a suitable location to move the Lighthouse or the Keeper’s Quarters at the Light Station Complex area within Cape Lookout Village; the Galley at the Cape Lookout Coast Guard Complex was the only building with a low vulnerability score and, thus, reloca-tion was not an applicable adaptation strategy.

All the adaptation action cost estimates include costs affiliated with documenting each building in its new condi-tion (and for a historic structures report if one has yet to be written), as well as interpreting (minimally or extensively) the way the park has adapted each building to minimize climate-change effects. Additional actions that can be applied within the model include no action and annual maintenance. We did not include annual inflation rates within the cost estimates or within the annual budget allocations. A full description of the actions is provided in appendix 1, table 1.6, and the costs applied for each action to each building are provided in appendix 1, table 1.7. It is important to note that the costs esti-mated for each type of action being applied to each building are conservative (understated) given the additional burden of transportation and lodging needed at Cape Lookout National

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The Optimal Preservation Model 7

Seashore and that they were developed with the assumption of the NPS performing the work (not contracted work); however, the costs were consistently estimated based on building type and size. More research is needed to enhance the accuracy of these costs when the OptiPres Model is transferred to other park units.

The model uses a stochastic search algorithm (that is, simulated annealing) that randomly picks 1 year and one building and then randomly selects an action. It then projects the effect of that single change on each of the metrics, begin-ning with the initial conditions, over all 30 years. If the total resource value improves because of the change, then the change is retained until a better one is found. If the resource value does not improve, then the change is rejected and another one is selected. Additional model parameters are used to control how selective the algorithm is about how large an improvement is required for acceptance. If run many millions of times, the algorithm should converge on a near-optimal solution. In order to ensure this was the case, we also applied a local search algorithm in between runs of the simulated annealing algorithm. The dynamics of the projection over time are specific to the actions applied. As such, each action can affect the relative resource value of any given building (posi-tively or negatively), as well as reduce the vulnerability of a

specific building (fig. 3). More specific details on the model dynamics are provided in appendix 1, table 1.6.

We performed all our analyses in the R programming environment (R Core Development Team, 2017). Because of the large number of possible combinations of resources and actions, running the optimization algorithm in R would have taken a prohibitively long time. Instead, we wrote both the simulated annealing and local search algorithms in C++ and used the Rcpp (Eddelbuettel and Francois, 2011) and RcppArmadillo (Eddelbuettel and Sanderson, 2014) packages to embed the code in R as a function (see appendix 3 docu-ments available for download at https://doi.org/10.3133/ofr20181180). We then ran each of the different scenarios in R on the YETI High Throughput Computing System maintained by the U.S. Geological Survey.

We based the range of budget allocations included in this pilot study on realistic assumptions, including a no action sce-nario. We estimated the industry standard for continual pres-ervation of buildings in these districts (inspection, corrective maintenance, preventative maintenance, cyclic maintenance, and recurring maintenance) to be $222,000 annually. We set the “low” range of budget allocations at $50,000 (nearly $20,000 less than what would be required to perform only

Figure 2. Annual alternative actions considered in the Optimal Preservation Model. Primary categories included deferring action on a structure for a given year (no action), actions that are considered routine maintenance (annual maintenance), and proactive or reactive alternatives designed to adapt buildings to climate impacts (adaptation actions). The latter category includes seven distinct alternatives available to managers (middle column), each of which may share component subactions with other alternatives (right column).

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8 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

annual maintenance on each of the 17 buildings within a year). We set the “high” range of budget allocations at $500,000 (roughly twice the industry standard). To explore the uncer-tainty related to budget allocations, we ran 11 budget scenarios ranging from the low to the high allocations in $50,000 inter-vals, including one at $222,000.

Additionally, we included several other planning sce-narios in the model runs. Specifically, we explored the outcome if annual budgets were substantially increased (for example, through competitive grants or donation funding) every 5 years. For this scenario, we set the annual alloca-tion at $222,000 with $250,000 additional funding added in years 5, 10, 15, 20, 25, and 30. We ran a similar scenario with a reduced annual allocation of $70,000 (more realistic in terms of actual park budget funding received in recent years) and the same $250,000 increase every 5 years. In another scenario, we removed vulnerability from the model to explore how sensitive the model is to the vulnerability metrics. In a final scenario, we set the weight of the use potential value to zero so that the model only considers the buildings’ historical significance when calculating total resource values. We used this last scenario to test the importance of use potential, which received a lower weight than historical significance and was not as dynamic a variable as historical significance in terms of the effect of actions.

Model Results and InterpretationsWe tested the behavior and summarized the output of

the OptiPres Model under five different planning scenarios: (1) a baseline scenario of expected dynamics if no actions areimplemented to maintain buildings in the historic districts,(2) an uncertain budget, (3) periodic funding increases,(4) ignoring buildings’ vulnerability, and (5) excluding build-ings’ use potential from the calculation of resource value.Resource value (that is, weighted sum of historical signifi-cance attributes and use potential attributes) is a measurementof overall management performance, where higher resource

values mean better performance. The accumulated resource value 90 serves as the reference point for all scenarios because it is the sum of all 17 buildings’ historical significance scores and use potential scores, divided by the buildings’ vulnerability scores, in planning year 1.

The five planning scenarios were selected because NPS personnel perceived these as feasible future managerial con-texts, they were eventualities that the NPS personnel involved in the study wanted to explore during this pilot project, or both. Limited and uncertain budgets are status quo for many cultural resource managers, and periodic budget allocations enable special projects. Exploring the exclusion of vulnerabil-ity and use potential allows managers to better understand the effect of these objectives on model outcomes and enables the research team to evaluate the model’s performance. To assist in the interpretation of the results, we have included the costs of each action for the 17 buildings in appendix 1, table 1.7.

It is important to note that the modeling scenario results did not select some adaptation actions. The negative effect to overall resource value for two actions (that is, document and monitor, and active removal) seems to be driving the elimination of these actions for the optimal solutions, despite document and monitor having relatively low costs. Addition-ally, core and shell preservation with resilient materials did not appear in the modeling results. Because flooding is the primary climate-change effect included in the vulnerability attributes, a building’s vulnerability score is not substantially affected by this action, which includes costs more likely affili-ated with preventing rain and wind damage (for example, tin roofs and hurricane roof clips). Therefore, it is logical that the model finds the core and shell preservation with historic mate-rials more optimal because historic materials do not negatively affect a building’s resource value to the same extent as using more modern, storm-resistant materials.

Scenario 1—No Action

To illustrate the changes in resource values of buildings under different planning scenarios, a baseline scenario was

Figure 3. A conceptual diagram of the Optimal Preservation Model dynamics and the relations between actions, objectives, and values.

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Model Results and Interpretations 9

created. Under this scenario, no actions are applied to any buildings over the 30-year period. We estimated the accumu-lated resource values of all buildings at the beginning of the 30-year period (“beginning values” =90) and the accumulated values of all buildings at the end of 30-year period (“ending values”=52; fig. 4). The accumulated resource value of the historic buildings decreases rapidly with no adaptation actions taken, resulting in less than 60 percent of the original value remaining at the end of 30-year period. The substantial decline of resource value is caused by continuous decay of the build-ings’ condition and the lack of improvement in vulnerability scores under the “no action” scenario.

We also estimate the percentage of current and future resource value for each building under the “no action” sce-nario (fig. 5). The percentages that each building contributes to the accumulated resource value at the beginning of 30-year period is displayed in the chart on the left side of figure 5; percentages at the end of 30-year period are displayed to the right. The individual resource values of buildings were nearly

equivalent at the beginning of the period, whereas substantial differences in remaining value are expected by the end of the 30-year period with no actions applied. This finding suggests that dynamics of vulnerability and buildings’ condition are operating asymmetrically across the study area. The Light-house, Galley, Lifesaving Station, and 1907 Keepers Quarters at Cape Lookout Village account for larger percentages of the accumulated resource value than other buildings, whereas several buildings at Cape Lookout Village (O’Boyle Bryant, Jetty Workers House 1, Jetty Workers House 2, and Gordon Willis House) account for relatively small percentages of resource values.

Scenario 2—An Uncertain Budget

We simulated the effect of an uncertain budget by run-ning the model under a range of budget levels, from $50,000 to $500,000 in steps of $50,000. The expected total resource value of the optimal portfolio of actions applied across the 17 historic buildings for the budget levels is displayed in figure 6. These results suggest at least three things: (1) that spending any money to manage even a subset of buildings is better than doing nothing; (2) that spending more money leads to improved management performance; and (3) that for this range of budgets examined, the relation between budget and expected benefit does not result in an obvious “shoul-der” in the curve, making it difficult to identify the budget level at which the cost-benefit ratio changes. In the following sections, we present the management portfolios used to gener-ate figure 6. Because the analysis of these portfolios requires examining multiple parts of the model, we will only present results for the $50,000, $222,000, and $500,000 budget levels.

Portfolio for a Budget of $50,000The total annual costs for maintenance of all build-

ings, $67,800 (appendix 1, table 1.7), was more than avail-able under this scenario, limiting the number of buildings that could receive even minimal attention. The optimal set of actions under the $50,000 budget suggests that a focus on maintaining 13 of the 17 buildings leads to the best manage-ment outcome (fig. 7). The percentage of total resource value and relative total cost of each building is provided in figure 8. The resource values of two unmanaged buildings (Gordon Willis House and O’Boyle Bryant House at Cape Lookout Vil-lage) declined substantially and accounted for approximately 1 percent of the accumulated resource value of all buildings. This budget allocation results in declining condition for all the buildings, declining significance for the four unmanaged buildings (“remaining significance” curve), stable use poten-tial of all the buildings (“use potential” curve), and slightly declining resource value for each of the buildings, with most drastic declines for the four unmanaged buildings (“resource value” curve; appendix 2, fig. 2.1). Despite the relatively stable “use potential” curve, the declines in condition of all

Figure 4. Accumulated resource values of all buildings at the beginning and end of the 30-year planning horizon under a “no action” scenario. Units of accumulated resource values are relative and on a constructed, composite scale.

Beginning values Ending valuesScenarios

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10 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

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Model Results and Interpretations 11

17 buildings suggest that an annual budget of $50,000 is insufficient to enable the continued use of buildings for park operations, for public visitation, or both.

The optimal solution seems to suggest that two of the buildings (Gordon Willis House and O’Boyle Bryant House at Cape Lookout Village) with the lowest beginning significance scores (the “remaining significance” curve begins near 0.2), which also have low use potential scores (the “use poten-tial” curve begins near 0.0), are not high-priority buildings (see appendix 2, fig. 2.1). However, the two other buildings selected to be unmaintained during the 30-year planning horizon (the Keeper’s Quarters at Cape Lookout Village and the Church at Portsmouth Village) are likely high priorities for park managers, and the loss of significance could represent an undesired management situation because the Keeper’s Quar-ters functions as a visitor center and houses volunteers, and the Church, an iconic building in Portsmouth Village, serves as a meeting place for the Friends of Portsmouth Island. It is important to note that this finding is likely related to the fact that managers placed higher weight on historical significance than on use potential. If use potential was given more weight, it is possible that buildings that are used for operations or open for visitation would be selected when annual budget alloca-tions are insufficient to simply maintain all buildings. Given the current weighting scheme, the model prioritizes build-ings and management options in such a way that (1) the full $50,000 annual budget is expended and (2) the highest total resource value can be achieved. This suggested that the four

buildings selected for “no action” minimized losses to total resource value and—under the current specification of objec-tives, attributes, and their weights—should go unmanaged for the entire 30-year horizon. However, the declines in condition for all buildings (even those receiving annual maintenance) indicates that none will be suitable for park operations, visitor access, or third-party use within 20 years; we recognize that this model is not fully accounting for declines in use potential and are working to rectify this limitation for future applica-tions of the OptiPres Model.

Portfolio for a Budget of $222,000The optimal strategy under this budget allocation

suggested relocation (or elevation and relocation) of some buildings during the planning period and that other buildings should receive core and shell preservation treatments early in the planning window (fig. 9). Funds to perform annual maintenance are sufficient for each of the 17 buildings under this scenario. However, foregoing annual maintenance on some buildings provided enough savings in some years to enable higher-cost adaptation actions (for example, reloca-tion, elevation, and core and shell preservation) to be applied to other buildings; in this scenario, the budget was only large enough to consider those buildings that had the lowest costs for this class of actions. The consequence of trading off management of some buildings and not managing others, is that the resource value of those structures not receiving preservation or adaptation treatments (that is, those receiving ‘no action’ or ‘annual maintenance’) tended to decline slightly faster. Thus, actions that required short-term neglect of some buildings seemed to be pushed to the end of the planning horizon because that preserved the most resource value for the longest period.

Under this budget allocation, the Gordon Willis House and O’Boyle Bryant House at Cape Lookout Village are now candidates for relocation. This had the effect of increasing their condition, while simultaneously lowering their remain-ing historical significance (appendix 2, fig. 2.2). This same pattern of changes to condition and historical significance also occurred for the Frank Gaskill House and Summer Kitchen at Portsmouth Village and Jetty Worker’s House 1 at Cape Lookout Village. The buildings selected are associated with relatively low costs for relocation (most cost-effective way to reduce vulnerability and improve accumulated resource value).

The total resource value under this scenario increased by nearly 50 percent of the value under the previous scenario of a $50,000 annual budget. The relative proportion of accu-mulated value of each building under this budget differed from the previous scenario (fig. 10). Relative to all buildings, the Summer Kitchen at Portsmouth Village had the highest accumulated value. The Galley Lighthouse at Cape Lookout Village and Frank Gaskill House at Portsmouth Village also

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Figure 6. Expected total resource value of the optimal management portfolio at the end of the 30-year period, as a function of annual budget and compared to expected total resource value when no management is applied during the same period. Units of accumulated resource values are relative and on a constructed, composite scale.

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12 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

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Model Results and Interpretations 13

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illis

Hou

se C

LV (3

%)

Jetty

Wor

kers

Hou

se 2

CLV

(3%

)

Chur

ch P

V (5

%)

Scho

ol P

V (4

%)

Post

Offi

ce P

V (4

%)

Life

savi

ng S

tatio

n PV

(5%

)Su

mm

er K

itche

n PV

(13%

)

Was

hing

ton−

Robe

rts H

ouse

PV

(4%

)

Fran

k Ga

skill

Hou

se P

V (7

%)

Henr

y Pi

gott

Hous

e PV

(4%

)

Sum

mer

Kitc

hen

PV (8

%)

Life

savi

ng S

tatio

n CL

V (7

%)

O’Bo

yle

Brya

nt H

ouse

CLV

(9%

)

Galle

y (C

oast

Gua

rd C

LV) (

4%)

Jetty

Wor

kers

Hou

se 1

CLV

(9%

)

Gord

on W

illis

Hou

se C

LV (7

%)

Jetty

Wor

kers

Hou

se 2

CLV

(2%

)

Chur

ch P

V (6

%)

Scho

ol P

V (4

%)

Post

Offi

ce P

V (4

%)

Life

savi

ng S

tatio

n PV

(9%

)

1907

Kee

per’s

Qua

rters

CLV

(5%

)

K eep

er’s

Qua

rters

CLV

(6%

)

Ligh

thou

se C

LV (1

6%)

Was

hing

ton−

Robe

rts H

ouse

PV

(4%

)

Fran

k Ga

skill

Hou

se P

V (9

%)

Henr

y Pi

gott

Hous

e PV

(3%

)

Figu

re 1

0.

The

prop

ortio

n of

eac

h bu

ildin

g’s

accu

mul

ated

val

ue a

nd to

tal c

ost u

nder

sce

nario

2 a

nd a

n an

nual

bud

get o

f $22

2,00

0. T

otal

acc

umul

ated

reso

urce

val

ue a

nd to

tal

scen

ario

exp

endi

ture

are

pro

vide

d in

par

enth

eses

afte

r the

figu

re ti

tles,

resp

ectiv

ely.

[CLV

, Cap

e Lo

okou

t Vill

age;

%, p

erce

nt; P

V, P

orts

mou

th V

illag

e]

Figu

re 9

. Op

timal

act

ions

iden

tifie

d un

der S

cena

rio 2

and

a $

222,

000

annu

al b

udge

t allo

catio

n. [C

LV, C

ape

Look

out V

illag

e; P

V, P

orts

mou

th V

illag

e]

Year

13

57

911

1315

1719

2123

2527

29

No

actio

n

Annu

al m

aint

enan

ce

Docu

men

t and

mon

itor

Activ

e re

mov

al

Core

and

she

ll pr

eser

vatio

n (h

isto

ric m

ater

ials

)

Core

and

she

ll pr

eser

vatio

n (re

silie

nt m

ater

ials

)

Elev

ate

Relo

cate

Elev

ate

and

relo

cate

Ligh

thou

se C

LV

Keep

er’s

Qua

rters

CLV

1907

Kee

per’s

Qua

rters

CLV

Life

savi

ng S

tatio

n CL

V

Galle

y (C

oast

Gua

rd C

LV)

O’Bo

yle

Brya

nt H

ouse

CLV

Gord

on W

illis

Hou

se C

LV

Jetty

Wor

kers

Hou

se 1

CLV

Jetty

Wor

kers

Hou

se 2

CLV

Chur

ch P

V

Scho

ol P

V

Post

Offi

ce P

V

Life

savi

ng S

tatio

n PV

Sum

mer

Kitc

hen

PV

Was

hing

ton−

Robe

rts H

ouse

PV

Fran

k Ga

skill

Hou

se P

V

Henr

y Pi

gott

Hous

e PV

Historic buildings

Page 24: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

14 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

contributed disproportionately to accumulated resource value under this scenario.

This scenario’s results (that is, the industry standard) illustrate that the available budget context affects the deci-sion; that is, buildings regarded as not worth managing when budgets are low (figs. 7–8) may be worth managing when additional resources are available (figs. 9–10). Also, the addi-tional funding made four structures (Lifesaving Station, Post Office, and School at Portsmouth Village; and Galley [Coast Guard] at Cape Lookout Village) eligible for core and shell preservation actions at the beginning of the planning period (fig. 9). Applying core and shell preservation actions earlier in the planning period seems to result in larger marginal gains of condition improvement for buildings than applying this action later.

Additionally, the timing of relocation actions seems to reflect the tradeoffs inherent in receiving a large boost in resource value from removing vulnerability and the reduc-tion in relative value by lowering historical significance. The results specifically suggest that buildings that have high initial resource values and are more affordable to relocate (that is, those buildings that enable fewer tradeoffs by requir-ing a limited number of buildings to receive “do nothing” actions in the same year as relocations), should be moved earlier, whereas those that are more expensive to move should be moved later in the planning period (appendix 2, fig. 2.2). Buildings that have less resource value but also have more potential for large relative condition increases should be moved midway through the period for what seems to be the following reasons: they retain more relative resource value because it delays the decay rates, and they reduce long-term effects of not being able to maintain some buildings in the year during which relocation occurs.

To further explain these findings, we provide a couple specific examples to explain the pattern of results. The original significance value for the Summer Kitchen at Portsmouth Village was much higher than any of the other relocated buildings. However, relocating this building early reduced its significance but not by as much as the other relocated buildings. Therefore, more resource value could be main-tained over time by relocating this building early in the planning period, whereas relocating the other four buildings earlier would have resulted in a larger penalty and lowered the ending accumulated resource value. In fact, in test runs (not presented), reducing the strength of the effect of reloca-tion on historical significance resulted in relocation actions being applied earlier in the sequence. Additionally, some of the lower resource values were caused by the budget con-straint. For example, relocating the O’Boyle Bryant House at Cape Lookout Village meant some other buildings could not be managed in the relocation year. The model seemed to be pushing this effect toward the end of the planning period, likely because the declines in historical significance were accumulated more slowly during the 30-year planning period.

Portfolio for a Budget of $500,000The optimal portfolio for the largest budget we con-

sidered was very similar to the $222,000 budget outputs, except that the increase in potential spending meant more buildings could be managed (fig. 11). Relocation and annual maintenance actions dominated this solution, as in the $222,000 allocation, but “core and shell preservation (historic materials)” was chosen by the model for one building, the Galley (Coast Guard) at Cape Lookout Village. It is likely that this action was selected for the Galley because of the relatively low cost affiliated with this action for this building; the Galley (Coast Guard) at Cape Lookout Village and Summer Kitchen at Portsmouth Village have the lowest costs for core and shell preservation (historic materials). The Summer Kitchen at Portsmouth Village receives this preservation treatment as part of the relocate and elevate action applied in the same year. Therefore, this action alone seems to be a good strategy for improving the condition of a building, while maintaining its historical significance, for buildings already in low vulner-ability locations (that is, the Galley [Coast Guard] at Cape Lookout Village).

The accumulated value of buildings under this scenario (fig. 12) increases by 37 percent of accumulated value under the scenario of annual allocation of $222,000 (fig. 10). The percentage contribution of resource value for each build-ing was similar with the $222,000 scenario, except for the noticeable increase in relative value of a few buildings in Portsmouth Village, which were eligible for relocation and elevation under this budget scenario. Total expenditures under this scenario were about 70 percent higher than that spent under the $222,000 scenario.

The effect of this budget allocation on the aspect of resource value were virtually the same as those in the $222,000 budget scenario, with a few notable exceptions: the optimal timing of the relocation action for some buildings seems to have been moved earlier in the planning window (fig. 11 compared to fig. 9). For example, under a larger budget, moving the O’Boyle Bryant House at Cape Lookout Village occurs earlier in the planning period. This could be because the budget constraint under the previous $222,000 allocation caused two other buildings to go unmanaged when the O’Boyle Bryant House was moved. These results also are reflected in the total accumulated resource value (fig. 12) for this budget allocation, which was substantially higher than for the previous $222,000 allocation (fig. 10). Additional details on each building are provided in appendix 2, figure 2.3.

Page 25: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Model Results and Interpretations 15

Year

13

1113

1517

1921

2325

2729

Ligh

thou

se C

LV

Keep

er’s

Qua

rters

CLV

1907

Kee

per’s

Qua

rters

CLV

Life

savi

ng S

tatio

n CL

V

Galle

y (C

oast

Gua

rd C

LV)

O’Bo

yle

Brya

nt H

ouse

CLV

Gord

on W

illis

Hou

se C

LV

Jetty

Wor

kers

Hou

se 1

CLV

Jetty

Wor

kers

Hou

se 2

CLV

Chur

ch P

V

Scho

ol P

V

Post

Offi

ce P

V

Life

savi

ng S

tatio

n PV

Sum

mer

Kitc

hen

PV

Was

hing

ton−

Robe

rts H

ouse

PV

Fran

k Ga

skill

Hou

se P

V

Henr

y Pi

gott

Hous

e PV

No

actio

n

Annu

al m

aint

enan

ce

Docu

men

t and

mon

itor

Activ

e re

mov

al

Core

and

she

ll pr

eser

vatio

n (h

isto

ric m

ater

ials

)

Core

and

she

ll pr

eser

vatio

n (re

silie

nt m

ater

ials

)

Elev

ate

Relo

cate

Elev

ate

and

relo

cate

Historic buildings

57

9

Figu

re 1

1.

Optim

al a

ctio

ns id

entif

ied

unde

r sce

nario

2 a

nd a

$50

0,00

0 an

nual

bud

get a

lloca

tion.

[CLV

, Cap

e Lo

okou

t Vill

age;

PV,

Por

tsm

outh

Vill

age]

Ligh

thou

se C

LV (6

%)

Keep

er’s

Qua

rters

CLV

(4%

)

1907

Kee

per’s

Qua

rters

CLV

(8%

)

Life

savi

ng S

tatio

n CL

V (8

%)

O’Bo

yle

Brya

nt H

ouse

CLV

(2%

)Ga

lley

(Coa

st G

uard

CLV

) (7%

)

Jetty

Wor

kers

Hou

se 1

CLV

()5%

)

Gord

on W

illis

Hou

se C

LV (2

%)

Jetty

Wor

kers

Hou

se 2

CLV

(5%

)

Chur

ch P

V (4

%)

Scho

ol P

V (7

%)

Post

Offi

ce P

V (8

%)

Life

savi

ng S

tatio

n PV

(4%

)Su

mm

er K

itche

n PV

(10%

)

Was

hing

ton−

Robe

rts H

ouse

PV

(8%

)

Fran

k Ga

skill

Hou

se P

V (5

%)

Henr

y Pi

gott

Hous

e PV

(7%

)

Acc

umul

ated

val

ue (1

38)

Ligh

thou

se C

LV (3

%)

Keep

er’s

Qua

rters

CLV

(4%

)

1907

Kee

per’s

Qua

rters

CLV

(11%

)

Life

savi

ng S

tatio

n CL

V (1

3%)

O’Bo

yle

Brya

nt H

ouse

CLV

(5%

)Ga

lley

(Coa

st G

uard

CLV

) (2%

)

Jetty

Wor

kers

Hou

se 1

CLV

(5%

)

Gord

on W

illis

Hou

se C

LV (4

%)

Jetty

Wor

kers

Hou

se 2

CLV

(6%

)

Chur

ch P

V (4

%)

Scho

ol P

V (7

%)

Post

Offi

ce P

V (6

%)

Life

savi

ng S

tatio

n PV

(4%

)Su

mm

er K

itche

n PV

(5%

)W

ashi

ngto

n−Ro

berts

Hou

se P

V (8

%)

Fran

k Ga

skill

Hou

se P

V (5

%)

Henr

y Pi

gott

Hous

e PV

(8%

)

Tota

l cos

t ($5

,073

,700

)

Figu

re 1

2.

The

prop

ortio

n of

eac

h bu

ildin

g’s

accu

mul

ated

val

ue a

nd to

tal c

ost u

nder

Sce

nario

2 a

nd a

n an

nual

bud

get o

f $50

0,00

0. T

otal

acc

umul

ated

reso

urce

val

ue a

nd to

tal

scen

ario

exp

endi

ture

are

pro

vide

d in

par

enth

eses

afte

r the

figu

re ti

tles,

resp

ectiv

ely.

[CLV

, Cap

e Lo

okou

t Vill

age;

%, p

erce

nt; P

V, P

orts

mou

th V

illag

e]

Page 26: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

16 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Scenario 3—Accounting For Periodic Funding Increases

Portfolio For A Budget Of $70,000 With A Surge Of $225,000 Every 5 Years

The optimal portfolio for this scenario with a low budget allocation (but one in which annual maintenance could be performed on all buildings in any given year) suggested that some buildings could be moved when a surge in total budget allocated occurred every 5 years (fig. 13). Under this scenario, all buildings were managed but not in every year of the plan-ning period. Unlike the $222,000 scenario (fig. 9), which targeted relocation and elevation actions at the beginning or the end of the 30-year period, the optimal strategy of this sce-nario ($70,000 annually with $225,000 surges every 5 years) dispersed the action of relocation and elevation actions more evenly over time (fig. 13). Similarly, lower-cost relocations occurred early, and higher-cost relocations were postponed towards the end of the planning horizon.

The outcomes of a budget allocation that included periodic funding increases (appendix 2, fig. 2.4) were similar to those of the $222,000 scenario (appendix 2, fig. 2.2), with the exception of the relative significance losses for several of the buildings. The similarities in total accumulated resource value between these scenarios (slightly lower values for this budget allocation compared to the $222,000 scenario; figs. 14 and 10, respectively) may be caused by fact that the relocation and annual maintenance actions dominated the solutions for both scenarios.

Portfolio For A Budget Of $222,000 With A Surge Of $225,000 Every 5 Years

The optimal portfolio for this budget allocation (fig. 15) suggests that more buildings could be candidates for reloca-tion or relocation and elevation actions than in the scenario of annual budget of $222,000 (fig. 9). Similar to the $70,000 annual budget allocation with additional funding (fig. 13), relocation or relocation and elevation actions were selected in the years when the additional funding was allocated.

Interestingly, the core and shell preservation using historic materials action was not selected in this budget allocation (it was selected for one building, the Galley at Cape Lookout Village, under the annual budget allocation of $500,000; fig. 11). It is possible that the marginal gain in resource value for these buildings under this budget allo-cation (fig. 16) compared to that of the $500,000 scenario (fig. 12) might be greater for the relocation or relocation and elevation adaptation strategies than for the core and shell preservation treatment. Although the actual expendi-tures under this scenario were about 87 percent of the actual expenditures of $500,000 annual allocation scenario (about $4.48 million compared to about $5.07 million), the total accumulated resource value under this scenario was very

similar (130 compared to 138, respectively) with the scenario of annual budget of $500,000 (figs. 16 and 12, respectively). Additional information for each building’s relative resource value is provided in appendix 2, figure 2.5.

Scenario 4—Ignoring Vulnerability

Portfolio For A Budget Of $222,000 Without Vulnerability

The optimal management strategy under this scenario is to select actions of core and shell preservation using historic materials and annual maintenance (fig. 17). Relocation and elevation actions were likely not selected under this scenario because these actions included the same historic preserva-tion treatment (that is, they both increase the condition of the building to NPS standards) but would reduce the relative significance of the buildings. Because vulnerability was not considered, the additional costs for actions that address sea level rise and storm-related flooding were not justified. The buildings selected seem to be a function of cost (fig. 18) and condition (improved condition ratings; see appendix 2, fig. 2.6); however, it is not quite clear why the preservation treatments typically occurred in the middle of the planning horizon but it is likely related to reducing the effect of decay rates posttreatment.

In this scenario, the total accumulated resource value (fig. 18) is calculated by accumulating the annual resource value over the planning horizon but not penalizing the final score by a building’s vulnerability assessment. As a result, the model does not attempt to lower a building’s vulnerability and the resulting accumulated resource value for this scenario (fig. 18) is higher than in the $222,000 with vulnerability (fig. 10) scenario (305 compared to 101, respectively).

Scenario 5—Excluding The Attributes Of “Use Potential”

Portfolio For A Budget Of $222,000 Without Use Potential

The optimal portfolio for this scenario suggested that the core and shell preservation using the historic materials action was more likely to be chosen if the historical significance of buildings were given more weight (fig. 19). Four buildings with high historical significance (the Life-Saving Station, Post Office, and School at Portsmouth Village; and Galley at Cape Lookout Village) were candidates for historical preservation action at the beginning of 30-year period. Unlike the earlier $222,000 scenario with use potential in which relocation and elevation was selected for the Summer Kitchen at Portsmouth Village at the beginning of the planning horizon (fig. 9), this action was selected for the Summer Kitchen at the end of 30-year period under this scenario (fig. 19). We infer that

Page 27: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Model Results and Interpretations 17

Figu

re 1

3.

Optim

al a

ctio

ns id

entif

ied

unde

r sce

nario

3 a

nd a

$70

,000

ann

ual b

udge

t allo

catio

n w

ith a

n ad

ditio

nal $

225,

000

ever

y 5

year

s. [C

LV, C

ape

Look

out V

illag

e; P

V,

Ports

mou

th V

illag

e]

Yea

r

13

57

911

1315

1719

2123

2527

29

Ligh

thou

se C

LV

Keep

er’s

Qua

rter

s CL

V

1907

Kee

per’s

Qua

rter

s CL

V

Life

savi

ng S

tatio

n CL

V

Gal

ley

(Coa

st G

uard

CLV

)

O’B

oyle

Bry

ant H

ouse

CLV

Gor

don

Will

is H

ouse

CLV

Jetty

Wor

kder

Hou

se 1

CLV

Jetty

Wor

kers

Hou

se 2

CLV

Chur

ch P

V

Scho

ol P

V

Post

Offi

ce P

V

Life

savi

ng S

tatio

n PV

Sum

mer

Kitc

hen

PV

Was

hing

ton−

Robe

rts

Hou

se P

V

Fran

k G

aski

ll H

ouse

PV

Hen

ry P

igot

t Hou

se P

V

No

actio

n

Ann

ual m

aint

enan

ce

Doc

umen

t and

mon

itor

Act

ive

rem

oval

Core

and

she

ll pr

eser

vatio

n (h

isto

ric m

ater

ials

)

Core

and

she

ll pr

eser

vatio

n (r

esili

ent m

ater

ials

)

Elev

ate

Relo

cate

Elev

ate

and

relo

cate

Historic buildings

Ligh

thou

se C

LV (8

%)

Keep

er’s

Qua

rters

CLV

(5%

)

1907

Kee

per’s

Qua

rters

CLV

(6&

)Li

fesa

ving

Sta

tion

CLV

(6%

)O’

Boyl

e Br

yant

Hou

se C

LV (2

%)

Galle

y (C

oast

Gua

rd C

LV) (

8%)

Jetty

Wor

kers

Hou

se 1

CLV

(6%

)

Gord

on W

illis

Hou

se C

LV (1

%)

Jetty

Wor

kers

Hou

se 2

CLV

(6%

)

Chur

ch P

V (4

%)

Scho

ol P

V (8

%)

Post

Offi

ce P

V (9

%)

Life

savi

ng S

tatio

n PV

(5%

)Su

mm

er K

itche

n PV

(11%

)

Was

hing

ton−

Robe

rts H

ouse

PV

(4%

)

Fran

k Ga

skill

Hou

se P

V (6

%)

Henr

y Pi

gott

Hous

e PV

(4%

)

Acc

umul

ated

val

ue (1

10)

Ligh

thou

se C

LV (5

%)

Keep

er’s

Qua

rters

CLV

(5%

)

1907

Kee

per’s

Qua

rters

CLV

(4%

)

Life

savi

ng S

tatio

n CL

V (7

%)

O’Bo

yle

Brya

nt H

ouse

CLV

(3%

)Ga

lley

(Coa

st G

uard

CLV

) (3%

)Je

tty W

orke

rs H

ouse

1 C

LV (8

%)

Gord

on W

illis

Hou

se C

LV (2

%)

Jetty

Wor

kers

Hou

se 2

CLV

(10%

)

Chur

ch P

V (5

%)

Scho

ol P

V (1

0%)

Post

Offi

ce P

V (9

%)

Life

savi

ng S

tatio

n PV

(6%

)Su

mm

er K

itche

n PV

(7%

)

Was

hing

ton−

Robe

rts H

ouse

PV

(3%

)

Fran

k Ga

skill

Hou

se P

V (8

%)

Henr

y Pi

gott

Hous

e PV

(3%

)

Tota

l cos

t ($3

,246

,700

)

Figu

re 1

4.

The

prop

ortio

n of

eac

h bu

ildin

g’s

accu

mul

ated

val

ue a

nd to

tal c

ost u

nder

sce

nario

3 a

nd a

n an

nual

bud

get o

f $70

,000

with

an

addi

tiona

l $22

5,00

0 ev

ery

5 ye

ars.

To

tal a

ccum

ulat

ed re

sour

ce v

alue

and

tota

l sce

nario

exp

endi

ture

are

pro

vide

d in

par

enth

eses

afte

r the

figu

re ti

tles,

resp

ectiv

ely.

[CLV

, Cap

e Lo

okou

t Vill

age;

%, p

erce

nt; P

V,

Ports

mou

th V

illag

e]

Page 28: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

18 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

No

actio

n

Ann

ual m

aint

enan

ce

Doc

umen

t and

mon

itor

Act

ive

rem

oval

Core

and

she

ll pr

eser

vatio

n (h

isto

ric m

ater

ials

)

Core

and

she

ll pr

eser

vatio

n (r

esili

ent m

ater

ials

)

Elev

ate

Relo

cate

Elev

ate

and

relo

cate

Year

Ligh

thou

se C

LV

Keep

er’s

Qua

rter

s CL

V

1907

Kee

per’s

Qua

rter

s CL

V

Life

savi

ng S

tatio

n CL

V

Gal

ley

(Coa

st G

uard

CLV

)

O’B

oyle

Bry

ant H

ouse

CLV

Gor

don

Will

is H

ouse

CLV

Jetty

Wor

kers

Hou

se 1

CLV

Jetty

Wor

kers

Hou

se 2

CLV

Chur

ch P

V

Scho

ol P

V

Post

Offi

ce P

V

Life

savi

ng S

tatio

n PV

Sum

mer

Kitc

hen

PV

Was

hing

ton−

Robe

rts

Hou

se P

V

Fran

k G

aski

ll H

ouse

PV

Hen

ry P

igot

t Hou

se P

VHistoric buildings

1113

1517

1921

2325

2729

13

57

9

Figu

re 1

5.

Optim

al a

ctio

ns id

entif

ied

unde

r sce

nario

3 a

nd a

$22

2,00

0 an

nual

bud

get a

lloca

tion

with

an

addi

tiona

l $22

5,00

0 ev

ery

5 ye

ars.

[CLV

, Cap

e Lo

okou

t Vill

age;

PV,

Po

rtsm

outh

Vill

age]

Ligh

thou

se C

LV (6

%)

Keep

er’s

Qua

rters

CLV

(4%

)

1907

Kee

per’s

Qua

rters

CLV

(9%

)

Life

savi

ng S

tatio

n CL

V (5

%)

O’Bo

yle

Brya

nt H

ouse

CLV

(2%

)Ga

lley

(Coa

st G

uard

CLV

) (7%

)Je

tty W

orke

rs H

ouse

1 C

LV (5

%)

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on W

illis

Hou

se C

LV (3

%)

Jetty

Wor

kers

Hou

se 2

CLV

(5%

)

Chur

ch P

V (4

%)

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ol P

V (7

%)

Post

Offi

ce P

V (7

%)

Life

savi

ng S

tatio

n PV

(4%

)Su

mm

er K

itche

n PV

(11%

)W

ashi

ngto

n−Ro

berts

Hou

se P

V (8

%)

Fran

k Ga

skill

Hou

se P

V (6

%)

Henr

y Pi

gott

Hous

e PV

(7%

)

Acc

umul

ated

val

ue (1

30)

Ligh

thou

se C

LV (3

%)

Keep

er’s

Qua

rters

CLV

(4%

)

1907

Kee

per’s

Qua

rters

CLV

(13%

)

Life

savi

ng S

tatio

n CL

V (5

%)

O’Bo

yle

Brya

nt H

ouse

CLV

(6%

)Ga

lley

(Coa

st G

uard

CLV

) (2%

)Je

tty W

orke

rs H

ouse

1 C

LV (6

%)

Gord

on W

illis

Hou

se C

LV (5

%)

Jetty

Wor

kers

Hou

se 2

CLV

(7%

)

Chur

ch P

V (3

%)

Scho

ol P

V (7

%)

Post

Offi

ce P

V (7

%)

Life

savi

ng S

tatio

n PV

(4%

)Su

mm

er K

itche

n PV

(5%

)W

ashi

ngto

n−Ro

berts

Hou

se P

V (9

%)

Fran

k Ga

skill

Hou

se P

V (6

%)

Henr

y Pi

gott

Hous

e PV

(9%

)

Tota

l cos

t ($4

,486

,300

)

Figu

re 1

6.

The

prop

ortio

n of

eac

h bu

ildin

g’s

accu

mul

ated

val

ue a

nd to

tal c

ost u

nder

sce

nario

3 a

nd a

n an

nual

bud

get o

f $22

2,00

0 w

ith a

n ad

ditio

nal $

225,

000

ever

y 5

year

s.

Tota

l acc

umul

ated

reso

urce

val

ue a

nd to

tal s

cena

rio e

xpen

ditu

re a

re p

rovi

ded

in p

aren

thes

es a

fter t

he fi

gure

title

s, re

spec

tivel

y. [C

LV, C

ape

Look

out V

illag

e; %

, per

cent

; PV,

Po

rtsm

outh

Vill

age]

Page 29: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Model Results and Interpretations 19

111

1315

1719

2123

2527

293

57

9

No

actio

n

Ann

ual m

aint

enan

ce

Doc

umen

t and

mon

itor

Act

ive

rem

oval

Core

and

she

ll pr

eser

vatio

n (h

isto

ric m

ater

ials

)

Core

and

she

ll pr

eser

vatio

n (r

esili

ent m

ater

ials

)

Elev

ate

Relo

cate

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ate

and

relo

cate

Ligh

thou

se C

LV

Keep

er’s

Qua

rter

s CL

V

1907

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per’s

Qua

rter

s CL

V

Life

savi

ng S

tatio

n CL

V

Gal

ley

(Coa

st G

uard

CLV

)

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oyle

Bry

ant H

ouse

CLV

Gor

don

Will

is H

ouse

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Jetty

Wor

kers

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se 1

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Jetty

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kers

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se 2

CLV

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ch P

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ol P

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Post

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ce P

V

Life

savi

ng S

tatio

n PV

Sum

mer

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hen

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Was

hing

ton−

Robe

rts

Hou

se P

V

Fran

k G

aski

ll H

ouse

PV

Hen

ry P

igot

t Hou

se P

VHistoric buildings

Year

Figu

re 1

7.

Optim

al a

ctio

ns id

entif

ied

unde

r sce

nario

4 a

nd a

$22

2,00

0 an

nual

bud

get a

lloca

tion

with

out c

onsi

dera

tion

of v

ulne

rabi

lity.

[CLV

, Cap

e Lo

okou

t Vill

age;

PV,

Por

tsm

outh

Vi

llage

]

Ligh

thou

se C

LV (8

%)

Keep

er’s

Qua

rters

CLV

(8%

)

1907

Kee

per’s

Qua

rters

CLV

(7%

)Li

fesa

ving

Sta

tion

CLV

(7%

)O’

Boyl

e Br

yant

Hou

se C

LV (2

%)

Galle

y (C

oast

Gua

rd C

LV) (

6%)

Jetty

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kers

Hou

se 1

CLV

(4%

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on W

illis

Hou

se C

LV (2

%)

Jetty

Wor

kers

Hou

se 2

CLV

(4%

)

Chur

ch P

V (7

%)

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ol P

V (6

%)

Post

Offi

ce P

V (6

%)

Life

savi

ng S

tatio

n PV

(7%

)Su

mm

er K

itche

n PV

(8%

)

Was

hing

ton−

Robe

rts H

ouse

PV

(6%

)

Fran

k Ga

skill

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se P

V (5

%)

Henr

y Pi

gott

Hous

e PV

(6%

)

Acc

umul

ated

val

ue (3

05)

Ligh

thou

se C

LV (5

%)

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er’s

Qua

rters

CLV

(10%

)

1907

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per’s

Qua

rters

CLV

(7%

)Li

fesa

ving

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tion

CLV

(12%

)

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yle

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nt H

ouse

CLV

(5%

)

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y (C

oast

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rd C

LV) (

4%)

Jetty

Wor

kers

Hou

se 1

CLV

(5%

)

Gord

on W

illis

Hou

se C

LV (4

%)

Jetty

Wor

kers

Hou

se 2

CLV

(7%

)

Chur

ch P

V (9

%)

Scho

ol P

V (3

%)

Post

Offi

ce P

V (3

%)

Life

savi

ng S

tatio

n PV

(9%

)Su

mm

er K

itche

n PV

(3%

)

Was

hing

ton−

Robe

rts H

ouse

PV

(5%

)

Fran

k Ga

skill

Hou

se P

V (3

%)

Henr

y Pi

gott

Hous

e PV

(5%

)

Tota

l cos

t ($3

,142

,700

)

Figu

re 1

8.

The

prop

ortio

n of

eac

h bu

ildin

g’s

accu

mul

ated

val

ue a

nd to

tal c

ost u

nder

sce

nario

4 a

nd a

n an

nual

bud

get o

f $22

2,00

0 w

ithou

t con

side

ratio

n of

vul

nera

bilit

y.

Tota

l acc

umul

ated

reso

urce

val

ue a

nd to

tal s

cena

rio e

xpen

ditu

re a

re p

rovi

ded

in p

aren

thes

es a

fter t

he fi

gure

title

s, re

spec

tivel

y. [C

LV, C

ape

Look

out V

illag

e; %

, per

cent

; PV,

Po

rtsm

outh

Vill

age]

Page 30: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

20 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Ligh

thou

se C

LV (7

%)

Keep

er’s

Qua

rters

CLV

(5%

)

1907

Kee

per’s

Qua

rters

CLV

(6%

)

Life

savi

ng S

tatio

n CL

V (6

%)

O’Bo

yle

Brya

nt H

ouse

CLV

(4%

)Ga

lley

(Coa

st G

uard

CLV

) (10

%)

Jetty

Wor

kers

Hou

se 1

CLV

(9%

)

Gord

on W

illis

Hou

se C

LV (4

%)

Jetty

Wor

kers

Hou

se 2

CLV

(4%

)

Chur

ch P

V (4

%)

Scho

ol P

V (5

%)

Post

Offi

ce P

V (5

%)

Life

savi

ng S

tatio

n PV

(5%

)Su

mm

er K

itche

n PV

(11%

)

Was

hing

ton−

Robe

rts H

ouse

PV

(4%

)

Fran

k Ga

skill

Hou

se P

V (8

%)

Henr

y Pi

gott

Hous

e PV

(4%

)

Acc

umul

ated

val

ue (1

11)

Ligh

thou

se C

LV (6

%)

Keep

er’s

Qua

rters

CLV

(6%

)

1907

Kee

per’s

Qua

rters

CLV

(5%

)

Life

savi

ng S

tatio

n CL

V (7

%)

O’Bo

yle

Brya

nt H

ouse

CLV

(9%

)Ga

lley

(Coa

st G

uard

CLV

) (4%

)

Jetty

Wor

kers

Hou

se 1

CLV

(9%

)

Gord

on W

illis

Hou

se C

LV (7

%)

Jetty

Wor

kers

Hou

se 2

CLV

(2%

)

Chur

ch P

V (5

%)

Scho

ol P

V (4

%)

Post

Offi

ce P

V (4

%)

Life

savi

ng S

tatio

n PV

(9%

)Su

mm

er K

itche

n PV

(8%

)

Was

hing

ton−

Robe

rts H

ouse

PV

(4%

)

Fran

k Ga

skill

Hou

se P

V (9

%)

Henr

y Pi

gott

Hous

e PV

(3%

)

Tota

l cos

t ($2

,941

,300

)

Figu

re 2

0.

The

prop

ortio

n of

eac

h bu

ildin

g’s

accu

mul

ated

val

ue a

nd to

tal c

ost u

nder

sce

nario

5 a

nd a

n an

nual

bud

get o

f $22

2,00

0 w

ithou

t con

side

ratio

n of

use

pot

entia

l. To

tal a

ccum

ulat

ed re

sour

ce v

alue

and

tota

l sce

nario

exp

endi

ture

are

pro

vide

d in

par

enth

eses

afte

r the

figu

re ti

tles,

resp

ectiv

ely.

[CLV

, Cap

e Lo

okou

t Vill

age;

%, p

erce

nt; P

V,

Ports

mou

th V

illag

e]

111

1315

1719

2123

2527

293

57

9Ye

ar

No

actio

n

Ann

ual m

aint

enan

ce

Doc

umen

t and

mon

itor

Act

ive

rem

oval

Core

and

she

ll pr

eser

vatio

n (h

isto

ric m

ater

ials

)

Core

and

she

ll pr

eser

vatio

n (r

esili

ent m

ater

ials

)

Elev

ate

Relo

cate

Elev

ate

and

relo

cate

Ligh

thou

se C

LV

Keep

er’s

Qua

rter

s CL

V

1907

Kee

per’s

Qua

rter

s CL

V

Life

savi

ng S

tatio

n CL

V

Gal

ley

(Coa

st G

uard

CLV

)

O’B

oyle

Bry

ant H

ouse

CLV

Gor

don

Will

is H

ouse

CLV

Jetty

Wor

kers

Hou

se 1

CLV

Jetty

Wor

kers

Hou

se 2

CLV

Chur

ch P

V

Scho

ol P

V

Post

Offi

ce P

V

Life

savi

ng S

tatio

n PV

Sum

mer

Kitc

hen

PV

Was

hing

ton−

Robe

rts

Hou

se P

V

Fran

k G

aski

ll H

ouse

PV

Hen

ry P

igot

t Hou

se P

VHistoric buildings

Figu

re 1

9.

Optim

al a

ctio

ns id

entif

ied

unde

r sce

nario

5 a

nd a

$22

2,00

0 an

nual

bud

get a

lloca

tion

with

out c

onsi

dera

tion

of u

se p

oten

tial.

[CLV

, Cap

e Lo

okou

t Vill

age;

PV,

Po

rtsm

outh

Vill

age]

Page 31: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Insights From The Pilot Study 21

relocating this building earlier in the planning horizon would have resulted in a larger penalty on the resource value because of the greater weight on historical significance in this scenario (appendix 2, fig. 2.7) than the scenario that included use potential (appendix 2, fig. 2.2).

The total accumulated resource value (fig. 20) was computed as in the other scenarios except that use potential was not included in the calculation. We accomplished this by allocating all the weight to historical significance. Therefore, the accumulated resource values displayed in figure 20 are not directly comparable to the other scenarios’ accumulated resource value because it reflects an optimal strategy assuming only historical significance was to be maximized; yet, compar-ing this solution to the others indicates how much use potential affected the optimal strategy.

Comparing ScenariosTo compare effects of applied actions on the resource

values of buildings under different scenarios, we created a figure to show the composite, accumulated values of all build-ings and total expenditures under the eight scenarios (fig. 21; the resource values by building for each of the scenarios can be viewed in appendix 2, fig. 2.8). The resource values of all buildings under the scenarios of “no action” and annual allocation of $50,000 were lower than the original value of all buildings. The scenarios with higher budget allocations (scenarios 3–8) could improve the original resource values of all buildings, which suggests that adaptation actions can help maintain and (or) enhance historical significance and use potential of historic buildings.

Generally, a higher budget allocation results in higher accumulated resource value. However, the accumulated resource value of the scenario of allocation of $70,000 every year with an additional fund of $225,000 every 5 years was higher than the scenario of allocation of $222,000 every year. This finding is caused by the fact that the allocated budgets are not fully spent in several scenarios; for example, the scenario with a periodic funding increase uses 94 percent of allocated budget, whereas the constant funding scenario uses only 44 percent of the total allocated budget (fig. 22). The periodic allocation of additional funding makes efficient use of larger, more costly adaption actions for several buildings, resulting in slightly higher total accumulated resource value relative to the constant budget scenario. In addition, the high accumulated resource value achieved when disregarding vulnerability indi-cates that, based on current model specification, the quantifica-tion of resource value may be highly sensitive to vulnerability scores.

Insights From The Pilot StudyBuilding the OptiPres Model in its current state was

completed by using the best available data and iteratively examining the model assumptions. The model was constructed based on the objective of maximizing the total resource value of 17 buildings. Additionally, we ran four broad scenarios, including two with multiple budget allocations, to test the model’s assumptions, dynamics, and constraints with the goal of providing decision-making insights for managers and other relevant NPS personnel.

It is important to note that, for any optimization problem, there is a tradeoff between computational speed and closeness to some global optimum. In conservation planning, finding one exact, optimum solution is not essential, but it is important to generate many good solutions in a reasonable amount of time using the iterative heuristics for optimization problems. The simulated annealing algorithm is nondeterministic; each run will generate a different solution. For each scenario in this study, we ran the algorithm 100 times, which was aligned with the run times in other studies about conservation plan-ning using the simulated annealing algorithm (Westphal and others, 2007).

Additionally, it is important to note that, as with any modeling effort, we iterated through several revisions of model dynamics and associated metrics based on new infor-mation obtained during the project period. However, we could not address all considerations and limitations, but several key insights were gained through model exploration. These insights are described below.

Sufficient annual budget allocations are necessary to implement climate adaptation actions to historic buildings. Adaptation actions are costly and if park personnel are to maintain at least the current accumulated resource value, then sufficient fiscal appropriations (minimum of the industry standard) are necessary. Additionally, our results suggest that additional appropriations provided on regular intervals when annual appropriations are at the industry standard are nearly as efficient as annual appropriations at twice the rate of industry standards and increase the amount of accumulated resource value maintained to nearly the same level. However, periodic increases in funding may increase the risks posed to build-ings from the probability of a natural hazard (that is, damage or loss from a hurricane). Therefore, the OptiPres Model has planning utility related to fiscal efficiency by identifying a budget threshold necessary to maintain the historical signifi-cance and use potential of historical buildings while reducing vulnerability. Nevertheless, it will be important for managers to continue seeking additional stakeholder input to ensure that the adaptation actions selected align with the values of stakeholder groups and (or) are applied to buildings that hold relatively high importance for stakeholder groups. For the latter, it will be important to update the model to weight the adaptation actions by acceptability to a variety of external stakeholders (for example, community members, partner orga-nizations, and visitors) because certain actions may alter the

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22 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Figure 21. Accumulated value and total cost of all buildings for all budget scenarios. Units of accumulated values are on relative and on a constructed, composite scale.

0

2,000

4,000

6,000

0

100

200

300

Budget scenario

Tota

l cos

t, in

thoo

usan

ds o

f dol

lars

Accu

mul

ated

val

ue

Accumulated value Total cost

X−axis represents different budget scenarios.1: No action.2: Allocation of $50,000 every year.3: Allocation of $222,000 every year.4: Allocation of $500,000 every year.5: Allocation of $70,000 every year and an addtional $225,000 every five years.6: Allocation of $222,000 every year and an addtional $225,000 every five years.7: Allocation of $222,000 every year. without considertation of vulnerability.8: Allocation of $222,000 every year. without considertation of use potential.

Original value of all buildings

6 7 81 2 3 4 5

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Insights From The Pilot Study 23

Figure 22. Comparison of allocated budget versus actual expenditures for all budget scenarios.

100%

44%

56%

34%

66%

94%

6%

56%

44%

47%

53%

44%

56%

0

5,000

10,000

15,000

Budget scenario

Tota

l cos

t, in

thou

sand

s of

dol

lars

Remaining budget Used budget

X−axis represents different budget scenarios.1: Annual allocation of $50,000.2: Annual allocation of $222,000.3: Annual allocation of $500,000 every year.4: Annual allocation of $70,000 and an addtional $225,000 every five years.5: Annual allocation of $222,000 and an addtional $225,000 every five years.6: Annual allocation of $222,000 every year without considertation of vulnerability.7: Annual allocation of $222,000 every year without considertation of use potential.

6 71 2 3 4 5

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24 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

intangible resource values associated with people’s connec-tions to specific buildings.

Preferences regarding the valuation of a cultural resource (that is, weights applied to historical significance and use potential) affect the optimal adaptation strategies identified. Because maximizing total resource value of 17 buildings was the purpose behind our development of the OptiPres Model, the relative effect of each objective (based on weighting of historical significance and use potential, including associated attributes) must be clearly understood. We suggest that park managers, and perhaps cultural resource management person-nel at the national NPS Headquarters and (or) personnel at the National State Historic Preservation Office, have focused discussions about their preferences regarding historical resources and how these values relate to each of the attributes and subattributes before future applications of the OptiPres Model. Because objective weights reflect statements of subjec-tive values, they represent an additional source of variability and uncertainty in decision modeling. This uncertainty can be addressed in several ways, including a facilitated, consensus-based approach, surveying multiple stakeholders and calculat-ing average weights (that is, the method applied in this pilot study), and (or) grouping weights into several representative stakeholder “types” and conducting a sensitivity analysis of the effect on the portfolio strategy of variation in values.

Considerations For Advancing The Optipres Model

The NPS’s Climate Change Response Program perceives utility in the OptiPres Model for enhancing national park man-agement and supporting climate adaptation decision-making. After the conclusion of the second workshop at Cape Lookout National Seashore (see fig. 1), the Climate Change Response Program managers decided to provide funding to determine the transferability of the OptiPres Model by applying it to another National Park System unit. We have determined some additional considerations to include as improvements in subsequent model development. These considerations include the following:

• Clearly outlining how current replacement value datacan be integrated with other data from standardFederal databases to refine the cost estimates for the various actions.—We found that considerable effort from NPS staff was needed to determine the adapta-tion costs for buildings because of a high degree of variability in reporting to the various NPS facili-ties management databases. To reduce the burden on NPS staff in future applications of the OptiPres Model, continual work will be needed to determine standard costs per square footage based on dominant building materials.

• Development of a metric framework for assessing thecurrent historic integrity of buildings to include inthe historical significance calculations.—This model advancement may enable us to change the structure of the significance calculations by replacing the attri-bute “building condition” with “historic integrity” and integrating “building condition” into the cost estimates for the various adaptation actions (particu-larly, if it is integrated with the current replacement value of specific buildings). This advancement may also help us deal with the fact that “building condi-tion” and “use potential” are correlated but that the relations are not fully accounted for in this version of the OptiPres Model (that is, buildings in poor and perhaps some in fair condition would not have opera-tional, visitor, or third-party use but may retain some degree of use potential depending on anticipated budget allocations).

• Integrating social values data as a potential modelinput or lens through which to interpret modeloutputs.—For example, social values data collected at Cape Lookout National Seashore as part of a paral-lel research project suggests that specific adaptation actions (for example, moving or elevating buildings) are viewed unfavorably by several stakeholder groups and that the managers may benefit from OptiPres Model scenarios that remove or discount the value of these adaptation actions as options. Although replication of these social values data will likely not be feasible for the second park site to test the model because of the timeframe of review processes for studies that involve members of the public, we will seek opportunities to explore how stakeholders’ values can be used to affect and (or) interpret the model outputs.

• Development of additional objectives.—In ongoingdiscussions, we continue to sense that specifyingadditional objectives could enhance the usefulness of the model. Examples could be objectives related to minimizing “public risk” (for example, removing buildings in poor condition) or increasing “public enjoyment” (for example, prioritizing a building pres-ent on the landscape in good condition).

• Refining vulnerability data.—The limited differencesobserved in the vulnerability scores of the buildingsat Cape Lookout National Seashore suggest that refining the vulnerability analysis to a more localized scale could be advantageous. Specifically, the vulner-ability assessment methodology bins raw scores for exposure and raw scores for sensitivity, adds those binned scores together, and then bins the total score to develop the final static vulnerability metric on a 1–4 scale; additionally, the attributes that com-

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References Cited 25

pose the exposure and sensitivity metrics are added together without first weighting the scores based on different degrees of effect risk or damage. Recon-figuring how the vulnerability scores are computed may increase the model’s sensitivity, but using raw scores may not be particularly meaningful given the uncertainty in the data used to score the attributes and the stochastic nature of storm-related effects. Other considerations to increase model sensitivity include (1) changing the current vulnerability metric to a time-dependent persistence (risk) metric or (2) penal-izing adaptation action costs (for example, moving or elevating buildings) to reflect the time-dependent likelihood for increased risk of inundation at the time an action is applied (costlier if already inundated or greatly impacted by a storm event). Additionally, there will be a need to periodically re-estimate the vulnerability metrics because climate scenarios and projections of land cover change evolve with time.

• Incorporating stochastic storms and wind effects.—Coastal cultural resources—particularly those on bar-rier islands—are at risk from effects associated with natural hazards. These natural hazards are becoming exacerbated (in frequency, intensity, or both) by climate change, which highlights the importance of advancing the model to capture random events such as hurricanes and nor’easters. Integrating storms, with associated flooding and wind effects, as a random variable into the model also will allow us to explore nuances of climate change impacts—particu-larly to the condition class of a building—and adapta-tion actions for historic buildings because the model currently only accounts for chronic flooding effects. Moreover, incorporating stochastic events of natural hazards in the OptiPres Model will provide more information for decision makers and park managers about how to prioritize actions after a natural hazard. As more complete assessments of climate change effects are integrated into the model (for example, storm-related effects from wind and precipitation that penetrates buildings), specific adaptation actions that target nonflooding effects (for example, core and shell preservation treatments to improve adaptability that use resilient materials) may become favored within the model (rather than ignored).

• Enhance visualization and interpretations of model outputs.—Enhancing our data visualization and interpretation efforts may facilitate further think-ing and application of the model results, which may ultimately improve the usability of the model. Visualizations of data that illustrate how significance, use potential, vulnerability, and adaptation costs drive the model and interact across the 30-year forecast window will allow cultural resource managers and

NPS officials to determine optimal (that is, most efficient) annual budget levels. This will be particu-larly important as more buildings are included in any given modeling effort. Ultimately, the ability to clearly communicate data-driven support for specific budgets may enhance the NPS’s ability to receive the appropriations necessary to meet its cultural heritage preservation mandates.

• Incorporating dynamic outputs of vulnerability across the planning horizon.—Although the vulnerability scores for the historic buildings at Cape Look-out National Seashore only have slight changes between 2030 and 2050, the adaptation actions (for example, elevation and relocation) can dramatically change the vulnerability scores of historic buildings. Incorporating the dynamic outputs of vulnerabil-ity at each time step (that is, year) will help NPS officials understand the cultural resource vulner-ability changes across the 30-year planning horizon. More importantly, combining the dynamic outputs of conditions, integrity, use potential, and vulnerability would enable the calculation of annual accumulated resource values. These data could then be visualized as a running average of annual accumulated resource values across the 30-year planning horizon to help NPS officials understand the relative increases and decreases in resource values across the assortment of historic buildings under various budget scenarios.

Additionally, the OptiPres Model also could be used in adaptation planning of other cultural resources (for example, archeological resources), other types of park assets (for example, facilities and roads), or efforts that consider other types of climate change effects (for example, fire and drought). However, considerable effort would be needed to first develop the associated measurement frameworks for other cultural resources and assets to determine the relative importance of those resources and assets.

References Cited

Eddelbuettel, D., and Francois, R., 2011, Rcpp—Seamless R and C++ integration: Journal of Statistical Software, v. 40, no. 8, p. 1–18.

Eddelbuettel, D., and Sanderson, C., 2014, RcppArmadillo—Accelerating R with high-performance C++ linear algebra: Computational Statistics and Data Analysis, v. 71, p. 1054–1063

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26 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Fatorić, S., and Seekamp, E., 2017a, Assessing historical significance and use potential of buildings within historic districts—An overview of a measurement framework developed for climate adaptation planning: Raleigh, N.C., NC State Extension, AG–832, 12 p., accessed December 20, 2017, at https://content.ces.ncsu.edu/show_ep3_pdf/1513776878/23513/.

Fatorić, S., and Seekamp, E., 2017b, Evaluating a decision analytic approach to climate change adaptation of cultural resources along the Atlantic Coast of the United States: Land Use Policy, v. 68, p. 254–263. [Also available at https://doi.org/10.1016/j.landusepol.2017.07.052.]

Fatorić, S., and Seekamp, E., 2018, A measurement framework to increase transparency in historic preservation decision-making under changing climate conditions: Journal of Cultural Heritage, v. 30, p. 168–179. [Also available at https://doi.org/10.1016/j.culher.2017.08.006.]

Gregory, R., Failing, L., Harstone, M., Long, G., and McDaniels, T., 2012, Structured decision making—A practical guide to environmental management choices: Hoboken, N.J., John Wiley & Sons Inc., 312 p.

Henderson, M., and Seekamp, E., 2018, Battling the tides of climate change: The power of intangible cultural resource values to bind place meanings in vulnerable historic dis-tricts: Heritage, v. 1, no. 2, p. 220–238. [Also available at https://doi.org/10.3390/heritage1020015.]

Irwin, B.J., Wilberg, M.J., Jones, M.L., and Bence, J.R., 2011, Applying structured decision making to recreational fisher-ies management: Bethesda, Md., Fisheries, v. 36, no. 3, p. 113–122. [Also available at https://doi.org/10.1080/03632415.2011.10389083.]

National Park Service [NPS], 1995, How to apply the National Register criteria for evaluation: National Park Service, National Register Bulletin, accessed December 20, 2017, at https://www.nps.gov/nr/publications/bulletins/pdfs/nrb15.pdf.

National Park Service [NPS], 1998, Cultural resource man-agement guideline: National Park Service, NPS–28, accessed December 20, 2017, at http://obpa-nc.org/DOI-AdminRecord/0049518-0049814.pdf.

National Park Service [NPS], 2014, Climate change and stewardship of cultural resources: National Park Service, Policy Memorandum 14–02, accessed December 20, 2017, at https://www.nps.gov/policy/PolMemos/PM-14-02.htm.

National Park Service [NPS], 2016, Coastal hazards and climate change asset vulnerability protocol—Project description and methodology: Washington, D.C., National Park Service, NPS 999/132623, 6 p.

Peek, K., Tormey, B., Thompson, H., Young, R., Norton, S., McNamee, J., and Scavo, R., 2017, Cape Lookout National Seashore coastal hazards and climate change asset vul-nerability assessment: National Park Service Sustainable Operations and Climate Change Summary Report, 25 p.

R Core Development Team, 2017, R—A language and environment for statistical computing: Vienna, Austria, R Foundation for Statistical Computing. [Also available at https://www.R-project.org/]

Riggs, S.R., and Ames, D.V., 2007, Effect of storms on barrier island dynamics, Core Banks, Cape Lookout National Sea-shore, North Carolina, 1960–2001: U.S. Geological Survey Scientific Investigations Report 2006–5309, 73 p. [Also available at https://doi.org/10.3133/sir20065309.]

Rockman, M., Morgan, M., Ziaja, S., Hambrecht, G., and Meadow, A., 2016, Cultural resources climate change strat-egy: Washington, D.C., Cultural Resources, Partnerships, and Science and Climate Change Response Program, National Park Service, 60 p. [Also available at https://www.nps.gov/subjects/climatechange/upload/NPS-2016_Cultural-Resoures-Climate-Change-Strategy.pdf.]

Runge, M.C., Cochrane, J.F., Converse, S.J., Szymanski, J.A., Smith, D.R., Lyons, J.E., Eaton, M.J., Matz, A., Barrett, P., Nichols, J.D., Parkin, M.J., Motivans, K., and Brewer, D.C., 2013, Introduction to structured decision making (11th ed.): Shepherdstown, W.V., U.S. Fish and Wildlife Service, National Conservation Training Center.

Stein, B.A., Glick, P., Edelson, N., and Staudt, A., eds., 2014, Climate-smart conservation—Putting adaptation principles into practice: Washington, D.C., National Wildlife Federa-tion, 272 p. [Also available at https://www.nwf.org/~/media/PDFs/Global-Warming/2014/Climate-Smart-Conservation-Final_06-06-2014.pdf.]

Westphal, M.I., Field, S.A., and Possingham, H.P., 2007, Opti-mizing landscape configuration—A case study of woodland birds in the Mount Lofty Ranges, South Australia: Landscape and Urban Planning, v. 81, no. 1–2, p. 56–66. [Also avail-able at https://doi.org/10.1016/j.landurbplan.2006.10.015.]

Xiao, X., Seekamp, E., Post van der Burg, M., Eaton, M., Fatorić, S., and McCreary, A., 2019, Optimizing historic preservation under climate change—Decision support for cultural resource adaptation planning in national parks: Land Use Policy, v. 83, p. 379-389. [Also available at https://doi.org/10.1016/j.landusepol.2019.02.011.]

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27

Appendixes

Appendix 1. Optimal Preservation Model Objectives, Attributes, Weights, Actions, and Costs

Appendix 2. Value of Condition, Remaining Significance, and Use Potential for 17 Buildings Among Different Scenarios

Appendix 3. Computer Code for Optimal Preservation Model

Caption. Jetty Workers House II (circa 1920) in Cape Lookout Village (photograph credit: Erin Seekamp, 2015)

Caption. Jetty Workers House I (circa 1915) with 1907 Keeper’s Quarters (circa 1907) in the background (photograph credit: Erin Seekamp)

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28 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Appendix 1. Optimal Preservation Model Objectives, Attributes, Weights, Actions, and Costs

This appendix provides additional details of the multiple data sources that are used to populate the Optimal Preservation (OptiPres) Model. The OptiPres Model includes measures of a building’s resource value (historical significance and use poten-tial) and vulnerability (sensitivity and exposure), and cost estimates for adaptation actions. Additionally, some adaptation actions affect the attributes, subattributes, or both for resource value and vulnerability. In table 1.1, the objective “historical significance” is presented with descriptions of attributes and subattributes, the metrics and associated scores, and the relative weights assigned to the attributes and subattributes. In table 1.2, the objective “use potential” is presented with descriptions of attributes and subattributes, the metrics and associated scores, and the relative weights assigned to the attributes and subattributes. In table 1.3, the attribute “exposure” is presented with descriptions of subattributes and associated data sources. In table 1.4, the attribute “sensitivity” is presented with descriptions of subattributes and associated data sources. In table 1.5, the objective “vulnerabil-ity” is presented to illustrate how the two attributes (exposure and sensitivity) are combined to create a final binned vulnerability score. In table 1.6, the actions included within the OptiPres Model are defined and the associated model dynamics (changes to a building’s condition, the historic integrity of a building, and the vulnerability of a building). In table 1.7, the total costs for each action to be performed on each building are presented.

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Appendix 1. Optimal Preservation Model Objectives, Attributes, Weights, Actions, and Costs 29

Attr

ibut

es a

nd s

ubat

trib

utes

Ass

ocia

tion

to fu

ndam

enta

l pu

rpos

eCo

nditi

on o

f bui

ldin

gCh

arac

ter

Nat

iona

l reg

iste

r

Def

inin

g ch

arac

ter

Uni

quen

ess

to p

ark

Spat

ial s

igni

fican

ceEl

igib

ility

Desc

riptio

n

This

attr

ibut

e us

es th

e in

form

atio

n on

list

ed

fund

amen

tal r

esou

rce(

s)

in th

e pa

rk’s

foun

datio

n do

cum

ent1 t

o de

term

ine

if a

hist

oric

bui

ldin

g is

co

nsid

ered

a fu

ndam

enta

l or

non

fund

amen

tal

reso

urce

.

The

Nat

iona

l Par

k Se

rvic

e da

taba

se L

ist o

f Cla

ssifi

ed

Stru

ctur

es (L

CS)

2 is u

sed

to a

sses

s the

con

ditio

n of

th

e bu

ildin

g.

This

suba

ttrib

ute

eval

uate

s if

a bu

ildin

g is

the

prim

ary

(his

toric

) rea

son

that

resu

lted

in th

e de

vel-

opm

ent (

or re

settl

emen

t) of

the

hist

oric

dis

trict

or

is p

art o

f the

seco

ndar

y de

velo

pmen

t (or

rese

ttle-

men

t) of

the

dist

rict t

hat

occu

rred

bec

ause

of t

he

orig

inal

con

stru

ctio

n.

This

suba

ttrib

ute

cons

id-

ers t

he o

rigin

al (h

isto

ric)

func

tion

of th

e bu

ildin

g,

if its

func

tion

was

uni

que

with

in th

e pa

rk, o

r if t

here

ar

e a

num

ber o

f bui

ldin

gs

with

the

sam

e or

sim

ilar

func

tion.

The

geog

raph

ical

scal

e of

a

build

ing’

s his

toric

con

text

lis

ted

in th

e N

atio

nal

Reg

iste

r of H

isto

ric

Plac

es (N

RH

P)3 i

s use

d to

as

sess

the

suba

ttrib

ute

of

spat

ial s

igni

fican

ce.

The

elig

ibili

ty su

battr

ibut

e as

sess

es if

the

hist

oric

bu

ildin

g is

elig

ible

for

listin

g in

the

NR

HP.

Met

rics

and

scor

es4

Fund

amen

tal r

esou

rce

(2.2

)N

onfu

ndam

enta

l res

ourc

e (0

.9)

Goo

d co

nditi

on

(2.9

)Fa

ir co

nditi

on

(1.9

)Po

or c

ondi

tion

(1.1

)

Bui

ldin

g as

prim

ary

reas

on

for t

he h

isto

ric d

evel

op-

men

t of t

he d

istri

ct

(2.3

)B

uild

ing

as se

cond

ary

reas

on fo

r the

his

toric

de

velo

pmen

t of t

he

dist

rict

(1.1

)

Bei

ng u

niqu

e bu

ildin

g to

the

regi

on

(4.2

)B

eing

the

only

bui

ldin

g of

th

is ty

pe in

the

park

(3

.1)

Few

(2–3

) sim

ilar t

ypes

of

build

ing

pres

ent i

n th

e pa

rk

(1.9

)M

any

(>3)

sim

ilar t

ypes

of

build

ing

pres

ent i

n th

e pa

rk

(1.0

)

Nat

iona

l sig

nific

ance

(3

.4)

Stat

e si

gnifi

canc

e (2

.1)

Loca

l sig

nific

ance

(1

.1)

Elig

ible

(2

.0)

Non

elig

ible

(0

.0)

Attri

bute

or s

ubat

tribu

te w

eigh

t5

0.26

0.17

0.27

0.30

0.47

50.

525

0.41

0.59

1 Fou

ndat

ion

docu

men

ts fo

r nat

iona

l par

ks a

re a

vaila

ble

at h

ttps:

//par

kpla

nnin

g.np

s.gov

/foun

datio

nDoc

umen

ts.c

fm.

2 The

Lis

t of C

lass

ified

Stru

ctur

es (L

CS)

is a

vaila

ble

at h

ttps:

//hsc

l.cr.n

ps.g

ov/in

side

nps/

sear

ch.a

sp.

3 The

Nat

iona

l Reg

iste

r of H

isto

ric P

lace

s (N

RH

P) is

ava

ilabl

e at

http

s://n

pgal

lery

.nps

.gov

/nrh

p.4 S

core

s wer

e de

rived

usi

ng a

n el

icita

tion

of N

atio

nal P

ark

Serv

ice

(NPS

) and

Sta

te H

isto

ric P

rese

rvat

ion

Offi

ce (S

HPO

) sta

ff an

d re

flect

the

mea

n va

lue

calc

ulat

ed fo

r eac

h m

etric

from

the

elic

itatio

n.5 W

eigh

ts w

ere

deriv

ed u

sing

an

elic

itatio

n of

NPS

and

SH

PO st

aff a

nd re

flect

the

mea

n va

lue

calc

ulat

ed fo

r eac

h m

etric

from

the

elic

itatio

n.

Tabl

e 1.

1.

Hist

oric

al s

igni

fican

ce’s

attri

bute

s, s

ubat

tribu

tes,

and

met

rics

with

sco

res

incl

udin

g w

eigh

ts a

mon

g th

e at

tribu

tes

and

suba

ttrib

utes

.

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30 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National SeashoreTa

ble

1.2.

Us

e po

tent

ial’s

attr

ibut

es a

nd m

etric

s w

ith s

core

s in

clud

ing

wei

ghts

am

ong

the

attri

bute

s.

Use

pot

entia

l’s a

ttrib

utes

Ope

ratio

nal u

seTh

ird

part

y us

eVi

sito

r use

Inte

rpre

tive

use

Scie

ntifi

c us

e

Desc

riptio

n

This

attr

ibut

e ev

alua

tes i

f the

hi

stor

ic b

uild

ing

is u

sed

for p

ark

oper

atio

ns o

r has

pot

entia

l for

it

in th

e fu

ture

. It a

lso

eval

u-at

es p

ossi

ble

inve

stm

ent i

n th

e hi

stor

ic b

uild

ing

for p

ark

oper

a-tio

ns to

redu

ce th

e op

erat

iona

l us

e of

non

hist

oric

(non

cont

rib-

utin

g) b

uild

ing.

This

attr

ibut

e as

sess

es th

e cu

rren

t an

d po

tent

ial f

utur

e us

e of

the

build

ing

by th

e th

ird p

arty

th

roug

h le

ase

agre

emen

ts a

nd

conc

essi

ons.

This

attr

ibut

e ex

plor

es c

urre

nt

and

futu

re a

ctiv

e us

es o

f the

bu

ildin

g fo

r pub

lic v

isita

tion

in th

e hi

stor

ic d

istri

ct (o

r oth

er

spec

ified

are

a) o

f the

par

k.

The

park

’s L

ong-

Ran

ge In

terp

re-

tive

Plan

1 is u

sed

to a

sses

s cur

-re

nt a

nd fu

ture

act

ive

uses

of t

he

build

ing

for c

omm

unic

atin

g st

o-rie

s and

edu

catin

g vi

sito

rs o

f the

pa

rk. T

his a

ttrib

ute

dete

rmin

es

whe

ther

the

build

ing’

s int

erpr

e-tiv

e pl

an c

onve

ys p

rimar

y or

se

cond

ary

inte

rpre

tive

them

es.

This

attr

ibut

e ev

alua

tes i

f the

bu

ildin

g ha

s a p

oten

tial t

o yi

eld

new

scie

ntifi

c in

form

atio

n an

d va

lue.

Met

rics

and

scor

es2

Bui

ldin

g cu

rren

tly in

use

(4

.1)

Inve

stm

ent i

n hi

stor

ic b

uild

ing

for

oper

atio

ns c

an re

duce

non

his-

toric

bui

ldin

g’s u

se

(2.8

)B

uild

ing

has n

o cu

rren

t use

but

po

tent

ial u

se in

nex

t 5 y

ears

(2

.1)

Bui

ldin

g ha

s no

curr

ent u

se n

or

pote

ntia

l use

in n

ext 5

yea

rs

(1.1

)

Bui

ldin

g cu

rren

tly in

use

(1

.5)

Expr

esse

d po

tent

ial t

o us

e bu

ildin

g (1

.0)

No

expr

esse

d po

tent

ial t

o us

e bu

ildin

g (0

.25)

Bui

ldin

g op

en to

pub

lic w

ith h

igh

visi

tatio

n (4

.9)

Bui

ldin

g op

en to

pub

lic w

ith m

od-

erat

e vi

sita

tion

(3.9

)B

uild

ing

open

to p

ublic

with

low

vi

sita

tion

(3.0

)B

uild

ing

clos

ed to

pub

lic b

ut li

ke-

ly to

ope

n in

the

next

5 y

ears

(2

.1)

Bui

ldin

g cl

osed

to p

ublic

and

un

likel

y to

ope

n in

the

next

5

year

s (1

.0)

Prim

ary

them

es in

terp

rete

d cu

r-re

ntly

or i

n th

e ne

xt 5

yea

rs

(3.2

)Se

cond

ary

them

es in

terp

rete

d cu

r-re

ntly

or i

n th

e ne

xt 5

yea

rs

(2.1

)N

o cu

rren

t nor

pot

entia

l lin

k to

in

terp

retiv

e pl

an in

nex

t 5 y

ears

(1

.1)

Bui

ldin

g ha

s pot

entia

l to

yiel

d ne

w

scie

ntifi

c in

form

atio

n (1

.0)

Bui

ldin

g’s n

ew sc

ient

ific

info

rma-

tion

is n

ot d

eter

min

ed y

et

(0.5

)

Wei

ght3

0.17

0.12

0.17

0.26

0.28

1 Lon

g-R

ange

Inte

rpre

tive

Plan

s are

ava

ilabl

e at

http

s://w

ww.

nps.g

ov/s

ubje

cts/

hfc/

inte

rpre

tive-

plan

ning

.htm

.2 S

core

s wer

e de

rived

usi

ng a

n el

icita

tion

of N

atio

nal P

ark

Serv

ice

(NPS

) and

Sta

te H

isto

ric P

rese

rvat

ion

Offi

ce (S

HPO

) sta

ff an

d re

flect

the

mea

n va

lue

calc

ulat

ed fo

r eac

h m

etric

from

the

elic

itatio

n.3 W

eigh

ts w

ere

deriv

ed u

sing

an

elic

itatio

n of

NPS

and

SH

PO st

aff a

nd re

flect

the

mea

n va

lue

calc

ulat

ed fo

r eac

h m

etric

from

the

elic

itatio

n. H

isto

rical

sign

ifica

nce’

s wei

ght i

s 0.7

9, w

here

as u

se p

oten

tial’s

w

eigh

t is 0

.29.

Thi

s ind

icat

es th

at h

isto

rical

sign

ifica

nce

is n

early

thre

e tim

es a

s im

porta

nt a

s use

pot

entia

l.

Page 41: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Appendix 1. Optimal Preservation Model Objectives, Attributes, Weights, Actions, and Costs 31Ta

ble

1.3.

Us

e po

tent

ial’s

attr

ibut

es a

nd m

etric

s w

ith s

core

s in

clud

ing

wei

ghts

am

ong

the

attri

bute

s. E

xpos

ure’

s su

battr

ibut

es a

nd c

orre

spon

ding

dat

a so

urce

s.

Expo

sure

’s su

battr

ibut

es

Floo

ding

Stor

m s

urge

Sea

leve

l ris

eEr

osio

n an

d co

asta

l pro

xim

ityH

isto

rica

l flo

odin

g

Data

sou

rce1

Fede

ral E

mer

genc

y M

anag

emen

t A

genc

y Fl

ood

Map

s (pr

imar

y)Li

ght d

etec

tion

and

rang

ing

digi

tal e

leva

tion

mod

el o

r oth

er

elev

atio

n m

odel

Nat

iona

l Par

k Se

rvic

e-sp

ecifi

c Se

a, L

ake,

and

Ove

rland

Sur

ges

from

Hur

rican

es (S

LOSH

) m

odel

resu

lts (p

rimar

y)Li

ght d

etec

tion

and

rang

ing

digi

tal e

leva

tion

mod

el o

r oth

er

elev

atio

n m

odel

Nat

iona

l Par

k Se

rvic

e-sp

ecifi

c se

a le

vel r

ise

mod

elin

g (p

rimar

y)Li

ght d

etec

tion

and

rang

ing

digi

tal e

leva

tion

mod

el o

r oth

er

elev

atio

n m

odel

Stat

e or

U.S

. Geo

logi

cal S

urve

y er

osio

n ra

te b

uffer

s (pr

imar

y)Sh

orel

ine

prox

imity

buff

ers

Park

que

stio

nnai

re (p

rimar

y)St

orm

imag

ery

or re

conn

aiss

ance

1 Met

hods

des

crib

ed in

Pee

k an

d ot

hers

(201

7).

Sens

itivi

ty’s

suba

ttrib

utes

Floo

d da

mag

e po

tent

ial (

elev

ated

)St

orm

resi

stan

ce (c

ondi

tion)

His

tori

cal d

amag

ePr

otec

tive

engi

neer

ing

Data

sou

rce1

Park

que

stio

nnai

re (p

rimar

y)D

irect

mea

sure

men

ts o

f thr

esho

ld e

leva

tion

Park

que

stio

nnai

re (p

rimar

y)Fa

cilit

y M

anag

emen

t Sof

twar

e Sy

stem

da

taba

se

Park

que

stio

nnai

re (p

rimar

y)D

iscu

ssio

n w

ith p

ark

staf

Park

que

stio

nnai

re (p

rimar

y)Fi

eld

and

aeria

l im

ager

y an

alys

isW

este

rn C

arol

ina

Uni

vers

ity E

ngin

eerin

g In

vent

ory

1 Met

hods

des

crib

ed in

Pee

k an

d ot

hers

(201

7).

Tabl

e 1.

4.

Sens

itivi

ty’s

suba

ttrib

utes

and

cor

resp

ondi

ng d

ata

sour

ces.

Tabl

e 1.

5.

Vuln

erab

ility

’s m

etric

s an

d sc

ores

.

Scor

e le

vel

(ran

ging

from

2 to

8)

Vuln

erab

ility

’s m

etri

cs

Vuln

erab

ility

sco

re1

Bin

ned

vuln

erab

ility

sco

re

(ran

ging

from

1 to

4)

Bin

ned

expo

sure

at

trib

ute

scor

e (r

angi

ng fr

om 1

to 4

)

Bin

ned

sens

itivi

ty

attr

ibut

e sc

ore

(ran

ging

from

1 to

4)

Hig

h4

4≥7

4 M

oder

ate

33

63

Low

22

4 to

52

Min

imal

11

<41

1 Vul

nera

bilit

y sc

ore

= bi

nned

exp

osur

e sc

ore

+ bi

nned

sens

itivi

ty sc

ore

(Pee

k an

d ot

hers

, 201

7).

Page 42: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

32 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National SeashoreTa

ble

1.6.

Op

timal

Pre

serv

atio

n M

odel

ada

ptat

ion

actio

ns a

nd m

odel

dyn

amic

s.

Act

ion1

Def

initi

onM

odel

dyn

amic

s

Dep

reci

atio

n of

bu

ildin

g co

nditi

on2

Impr

ovem

ent i

n bu

ildin

g co

nditi

on3

Loss

of h

isto

ric

inte

grity

4Re

duce

d vu

lner

abili

ty

No

actio

nTh

is o

ptio

n al

low

s man

ager

s to

repu

rpos

e an

nual

mai

nten

ance

from

one

bui

ldin

g to

an

othe

r to

“cap

ture

” en

ough

mon

ey in

any

gi

ven

year

to a

pply

a c

ostly

ada

ptat

ion

actio

n to

ano

ther

bui

ldin

g.

Low

(8-p

erce

nt a

nnua

l los

s)—

App

lied

to b

uild

ings

in

“goo

d” c

ondi

tion

(Lis

t of

Cla

ssifi

ed S

truct

ures

[LC

S]

cond

ition

cla

ss sc

ore

of 3

).M

ediu

m (1

7-pe

rcen

t ann

ual

loss

)—A

pplie

d to

bui

ldin

gs

in “

fair”

con

ditio

n (L

CS

scor

e of

2).

Hig

h (2

5-pe

rcen

t ann

ual l

oss)

—A

pplie

d to

bui

ldin

gs in

“p

oor”

con

ditio

n (L

CS

scor

e of

1).

No

chan

ge (a

pply

ann

ual

depr

ecia

tion

rate

bas

ed

on c

urre

nt c

ondi

tion)

5-pe

rcen

t los

s in

inte

grity

(red

uctio

n in

ove

rall

sign

ifica

nce

scor

e at

time

of a

ctio

n).

No

chan

ge.

Ann

ual

mai

nten

ance

Reg

ular

, ann

ual m

aint

enan

ce th

at is

supp

osed

to

kee

p bu

ildin

gs in

goo

d co

nditi

on

(bas

e fu

nded

ope

ratio

ns; i

nspe

ctio

ns,

corr

ectiv

e m

aint

enan

ce, a

nd p

reve

ntat

ive

mai

nten

ance

). N

ote:

val

ues a

re lo

wer

co

rrec

tive

mai

nten

ance

cos

ts th

an fo

r cor

e an

d sh

ell p

rese

rvat

ion

beca

use

they

refle

ct

the

bare

min

imum

or m

aint

enan

ce o

f the

st

atus

quo

thro

ugh

appl

icat

ion

of sm

all

fixes

.

Low

(6-p

erce

nt a

nnua

l los

s)—

App

lied

to b

uild

ings

in

“goo

d” c

ondi

tion

(LC

S sc

ore

of 3

).M

ediu

m (1

0-pe

rcen

t ann

ual

loss

)—A

pplie

d to

bui

ldin

gs

in “

fair”

con

ditio

n (L

CS

scor

e of

2).

Hig

h (1

5-pe

rcen

t ann

ual l

oss)

—A

pplie

d to

bui

ldin

gs in

“p

oor”

con

ditio

n (L

CS

scor

e of

1).

No

chan

ge (a

pply

ann

ual

depr

ecia

tion

rate

bas

ed

on c

urre

nt c

ondi

tion)

.

0 pe

rcen

tN

o ch

ange

.

Page 43: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Appendix 1. Optimal Preservation Model Objectives, Attributes, Weights, Actions, and Costs 33

Act

ion1

Def

initi

onM

odel

dyn

amic

s

Dep

reci

atio

n of

bu

ildin

g co

nditi

on2

Impr

ovem

ent i

n bu

ildin

g co

nditi

on3

Loss

of h

isto

ric

inte

grity

4Re

duce

d vu

lner

abili

ty

Cor

e an

d sh

ell

pres

erva

tion—

hist

oric

m

ater

ials

Mai

nten

ance

of h

isto

ric c

hara

cter

of t

he

build

ing

and

its h

isto

ric m

ater

ials

(tha

t is

, sim

ilar a

s pos

sibl

e to

the

mat

eria

ls

used

in th

e or

igin

al c

onst

ruct

ion)

, whi

ch

incl

udes

ann

ual m

aint

enan

ce (i

nspe

ctio

n,

full

corr

ectiv

e m

aint

enan

ce, a

nd p

reve

ntiv

e m

aint

enan

ce) a

nd n

onan

nual

mai

nten

ance

to

brin

g to

stan

dard

(cyc

lic m

aint

enan

ce

and

recu

rrin

g m

aint

enan

ce, a

lso

refe

rred

to

as d

efer

red

mai

nten

ance

). Th

is a

ctio

n al

so in

clud

ed c

osts

affi

liate

d w

ith fu

lly

(ext

ensi

vely

) doc

umen

ting

the

reso

urce

in

its n

ew c

ondi

tion

(con

ditio

ns re

port)

.

0 pe

rcen

tB

uild

ing

chan

ges t

o “g

ood”

co

nditi

on c

lass

.0

perc

ent

No

chan

ge.

Cor

e an

d sh

ell

pres

erva

tion—

resi

lient

m

ater

ials

Mai

nten

ance

usi

ng h

igh

qual

ity, i

nnov

ativ

e,

and

func

tiona

l mat

eria

ls (m

etal

roofi

ng

and

fiber

cem

ent s

idin

g); a

nd a

dditi

onal

re

nova

tions

to im

prov

e th

e ph

ysic

al

resi

lienc

y of

the

build

ing

(inst

allin

g hu

rric

ane

clip

s, st

ainl

ess-

stee

l nai

ls, a

nd

win

dow

clip

s). T

his a

ctio

n al

so in

clud

ed

cost

s affi

liate

d w

ith fu

lly (e

xten

sive

ly)

docu

men

ting

the

reso

urce

in it

s new

co

nditi

on (c

ondi

tions

repo

rt), a

s wel

l as

min

imal

inte

rpre

tatio

n (f

or e

xam

ple,

on

e pa

nel s

ign

that

add

ress

es a

dapt

ing

to

clim

ate

chan

ge).

0 pe

rcen

tB

uild

ing

chan

ges t

o “g

ood”

co

nditi

on c

lass

.31

-per

cent

loss

inin

tegr

ity (r

educ

tion

inov

eral

l sig

nific

ance

scor

e at

tim

e of

actio

n).

No

chan

ge.

Elev

ate

This

act

ion

cons

ists

of (

1) b

ringi

ng th

e bu

ildin

g to

stan

dard

(cor

e an

d sh

ell

pres

erva

tion—

hist

oric

mat

eria

ls) a

nd (2

) ra

isin

g th

e m

inim

um fl

oor e

leva

tion

to

redu

ce th

e lik

elih

ood

of st

ruct

ural

dam

age

from

stor

m-r

elat

ed fl

oodi

ng, s

ea le

vel

rise,

or b

oth.

Thi

s act

ion

also

incl

uded

co

sts a

ffilia

ted

with

fully

(ext

ensi

vely

) do

cum

entin

g th

e re

sour

ce in

its n

ew

cond

ition

(his

toric

stru

ctur

e re

port)

, as w

ell

as m

inim

al in

terp

reta

tion

(for

exa

mpl

e,

one

pane

l sig

n th

at a

ddre

sses

ada

ptin

g to

cl

imat

e ch

ange

).

0 pe

rcen

tB

uild

ing

chan

ges t

o “g

ood”

co

nditi

on c

lass

.43

-per

cent

loss

inin

tegr

ity (r

educ

tion

inov

eral

l sig

nific

ance

scor

e at

tim

e of

act

ion,

assu

min

g hi

stor

icm

ater

ials

use

d in

pres

erva

tion)

.

Sens

itivi

ty c

hang

ed

to “

low

” (1

).

Tabl

e 1.

6.

Optim

al P

rese

rvat

ion

Mod

el a

dapt

atio

n ac

tions

and

mod

el d

ynam

ics.

—Co

ntin

ued

Page 44: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

34 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National SeashoreTa

ble

1.6.

Op

timal

Pre

serv

atio

n M

odel

ada

ptat

ion

actio

ns a

nd m

odel

dyn

amic

s.—

Cont

inue

d

Act

ion1

Def

initi

onM

odel

dyn

amic

s

Dep

reci

atio

n of

bu

ildin

g co

nditi

on2

Impr

ovem

ent i

n bu

ildin

g co

nditi

on3

Loss

of h

isto

ric

inte

grity

4Re

duce

d vu

lner

abili

ty

Rel

ocat

eTh

is a

ctio

n co

nsis

ts o

f (1)

brin

ging

the

build

ing

to st

anda

rd (c

ore

and

shel

l pr

eser

vatio

n—hi

stor

ic m

ater

ials

) and

(2)

mov

ing

the

build

ing

to a

less

vul

nera

ble

loca

tion

(with

in th

e hi

stor

ic d

istri

ct) t

o re

duce

the

likel

ihoo

d of

stru

ctur

al d

amag

e fr

om st

orm

-rel

ated

floo

ding

, sea

leve

l ris

e, o

r bot

h. T

his a

ctio

n al

so in

clud

ed

cost

s affi

liate

d w

ith fu

lly (e

xten

sive

ly)

docu

men

ting

the

reso

urce

in it

s new

lo

catio

n (c

ondi

tions

repo

rt), a

s wel

l as

exte

nsiv

e in

terp

reta

tion

(for

exa

mpl

e,

mul

tiple

pan

el si

gns t

hat a

ddre

ss a

dapt

ing

to

clim

ate

chan

ge).

0 pe

rcen

tB

uild

ing

chan

ges t

o “g

ood”

co

nditi

on c

lass

.30

-per

cent

loss

inin

tegr

ity (r

educ

tion

inov

eral

l sig

nific

ance

scor

e at

tim

e of

act

ion,

assu

min

g hi

stor

icm

ater

ials

use

d in

pres

erva

tion)

.

Sens

itivi

ty c

hang

ed

to “

low

” (1

).Ex

posu

re c

hang

ed to

“l

ow”

(1).

Elev

ate

and

relo

cate

This

act

ion

cons

ists

of (

1) b

ringi

ng th

e bu

ildin

g to

stan

dard

(cor

e an

d sh

ell

pres

erva

tion—

hist

oric

mat

eria

ls),

(2)

mov

ing

the

build

ing

to a

less

vul

nera

ble

loca

tion

(with

in th

e hi

stor

ic d

istri

ct),

and

(3)r

aisi

ng th

e m

inim

um fl

oor e

leva

tion

tore

duce

the

likel

ihoo

d of

stru

ctur

al d

amag

efr

om st

orm

-rel

ated

floo

ding

, sea

leve

lris

e, o

r bot

h. T

his a

ctio

n al

so in

clud

edco

sts a

ffilia

ted

with

fully

(ext

ensi

vely

)do

cum

entin

g th

e re

sour

ce in

its n

ewco

nditi

on (c

ondi

tions

repo

rt), a

s wel

l as

exte

nsiv

e in

terp

reta

tion

(for

exa

mpl

e,m

ultip

le p

anel

sign

s tha

t add

ress

ada

ptin

g to

clim

ate

chan

ge).

0 pe

rcen

tB

uild

ing

chan

ges t

o “g

ood”

co

nditi

on c

lass

.61

-per

cent

loss

inin

tegr

ity (r

educ

tion

inov

eral

l sig

nific

ance

scor

e at

tim

e of

act

ion,

assu

min

g hi

stor

icm

ater

ials

use

d in

pres

erva

tion)

.

Sens

itivi

ty c

hang

ed

to “

low

” (1

).Ex

posu

re c

hang

ed to

“l

ow”

(1).

Page 45: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Appendix 1. Optimal Preservation Model Objectives, Attributes, Weights, Actions, and Costs 35

Act

ion1

Def

initi

onM

odel

dyn

amic

s

Dep

reci

atio

n of

bu

ildin

g co

nditi

on2

Impr

ovem

ent i

n bu

ildin

g co

nditi

on3

Loss

of h

isto

ric

inte

grity

4Re

duce

d vu

lner

abili

ty

Doc

umen

t and

m

onito

rTh

is a

ctio

n in

clud

es c

osts

ass

ocia

ted

with

fu

lly (e

xten

sive

ly) d

ocum

entin

g th

e re

sour

ce (h

isto

ric st

ruct

ures

repo

rt) a

nd

erec

ting

a 6-

foot

cha

in-li

nk fe

nce

arou

nd a

bu

ildin

g an

d m

onito

ring

the

cond

ition

. The

fe

ncin

g re

duce

s the

pot

entia

l for

hum

an

inju

ry a

s the

re is

pot

entia

l for

the

build

ing

to d

eter

iora

te b

y th

e na

tura

l ele

men

ts.

This

act

ion

also

incl

udes

cos

ts a

ffilia

ted

with

ext

ensi

ve in

terp

reta

tion

(for

exa

mpl

e,

mul

tiple

pan

el si

gns t

hat a

ddre

ss a

dapt

ing

to

clim

ate

chan

ge).

Low

(4-p

erce

nt a

nnua

l los

s)—

App

lied

to b

uild

ings

in

“goo

d” c

ondi

tion

(LC

S sc

ore

of 3

).M

ediu

m (5

-per

cent

ann

ual

loss

)—A

pplie

d to

bui

ldin

gs

in “

fair”

con

ditio

n (L

CS

scor

e of

2).

Hig

h (6

-per

cent

ann

ual l

oss)

—A

pplie

d to

bui

ldin

gs in

“p

oor”

con

ditio

n (L

CS

scor

e of

1).

No

chan

ge (a

pply

ann

ual

depr

ecia

tion

rate

bas

ed

on c

urre

nt c

ondi

tion)

.

5-pe

rcen

t los

s in

inte

grity

appl

ied

annu

ally

from

yea

r of d

ecis

ion

forw

ard.

No

chan

ge.

Act

ive

rem

oval

This

act

ion

cons

ists

of p

hysi

cally

rem

ovin

g th

e bu

ildin

g fr

om th

e hi

stor

ic d

istri

ct (d

ebris

an

d ha

zard

dem

oliti

on) a

nd d

ispo

sing

the

mat

eria

ls a

ccor

ding

to F

eder

al g

uide

lines

(d

ebris

and

haz

ard

disp

osal

). Th

is a

ctio

n al

so in

clud

ed c

osts

affi

liate

d ex

tens

ive

inte

rpre

tatio

n (f

or e

xam

ple,

mul

tiple

pan

el

sign

s tha

t add

ress

ada

ptin

g to

clim

ate

chan

ge).

N/A

N/A

; con

ditio

n sc

ore

set

to 0

.90

-per

cent

per

man

ent

loss

in in

tegr

ity(b

uild

ing

rem

oved

from

land

scap

e;ex

tens

ive

inte

rpre

tatio

n to

“te

llth

e st

ory;

” re

tain

s 10

perc

ent i

nteg

rity

from

inte

rpre

tive

pane

ls).

Sens

itivi

ty re

mov

ed

(0).

Expo

sure

rem

oved

(0

).

1 Any

bui

ldin

g th

at d

oes n

ot h

ave

a H

isto

ric S

truct

ure

Rep

ort (

HSR

) als

o in

clud

es a

ssoc

iate

d co

sts t

o de

velo

p on

e fo

r all

actio

ns e

xcep

t “no

act

ion”

and

“an

nual

mai

nten

ance

.”2 A

n es

timat

e of

how

muc

h a

build

ing’

s con

ditio

n w

ould

ann

ually

dec

ay o

ver a

30-

year

pla

nnin

g ho

rizon

. Rat

es d

eter

min

ed th

roug

h co

nsul

tatio

n w

ith N

atio

nal P

ark

Serv

ice

(NPS

) per

sonn

el. T

he ra

te is

ap

plie

d to

onl

y th

e “c

ondi

tion

of th

e bu

ildin

g” a

ttrib

ute

but a

ffect

s the

bui

ldin

g’s h

isto

rical

sign

ifica

nce

and,

thus

, the

bui

ldin

g’s r

esou

rce

valu

e. N

/A is

not

app

licab

le.

3 An

estim

ate

of h

ow m

uch

a bu

ildin

g’s c

ondi

tion

wou

ld im

prov

e in

the

year

an

adap

tatio

n ac

tion

is a

pplie

d. In

the

year

an

actio

n is

app

lied,

the

mod

el w

ould

not

incl

ude

the

depr

ecia

tion

rate

; how

ever

, in

the

subs

eque

nt y

ears

(if n

o ac

tion

is a

pplie

d to

that

bui

ldin

g), t

he d

ecay

rate

wou

ld b

e re

intro

duce

d to

the

mod

el. R

ates

det

erm

ined

thro

ugh

cons

ulta

tion

with

NPS

per

sonn

el. T

he ra

te is

app

lied

to o

nly

the

“con

di-

tion

of th

e bu

ildin

g” a

ttrib

ute

but a

ffect

s the

bui

ldin

g’s h

isto

rical

sign

ifica

nce

and,

thus

, the

bui

ldin

g’s r

esou

rce

valu

e. N

/A is

not

app

licab

le.

4 An

estim

ate

of h

ow m

uch

hist

oric

al in

tegr

ity w

ould

be

lost

by

appl

ying

spec

ific

actio

ns, w

ith th

e as

sum

ptio

n th

at a

ny a

ctio

n w

ould

cha

nge

the

hist

oric

fabr

ic o

f the

bui

ldin

g an

d, c

onse

quen

tly, d

ecre

ase

its

inte

grity

. Rat

es d

eter

min

ed th

roug

h co

nsul

tatio

n w

ith N

PS p

erso

nnel

, the

n up

date

d to

refle

ct v

alue

s tha

t acc

ount

for p

erce

ntag

e of

inte

grity

loss

to th

e se

ven

crite

ria o

f int

egrit

y. T

his r

ate

is a

pplie

d to

eac

h of

th

e hi

stor

ical

sign

ifica

nce

attri

bute

s at t

he ti

me

of a

ctio

n, e

xcep

t for

con

ditio

n of

the

build

ing

(bec

ause

act

ions

eith

er im

prov

e or

dep

reci

ate

the

cond

ition

of t

he b

uild

ing)

, affe

ctin

g bo

th th

e bu

ildin

g’s h

isto

rical

si

gnifi

canc

e sc

ore

and

the

build

ing’

s res

ourc

e va

lue.

Tabl

e 1.

6.

Optim

al P

rese

rvat

ion

Mod

el a

dapt

atio

n ac

tions

and

mod

el d

ynam

ics.

—Co

ntin

ued

Page 46: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

36 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National SeashoreTa

ble

1.7.

Ad

apta

tion

actio

ns a

nd m

aint

enan

ce c

osts

for e

ach

of th

e 17

his

toric

bui

ldin

gs.

His

tori

c bu

ildin

gM

aint

enan

ce c

ost1 b

y ad

apta

tion

actio

n

Act

ive

rem

oval

Core

and

she

ll—

His

tori

c m

ater

ials

Core

and

she

ll—

Resi

lient

mat

eria

lsRe

loca

te th

e bu

ildin

gEl

evat

e th

e bu

ildin

gD

ocum

ent a

nd

mon

itor

Ann

ual

mai

nten

ance

Cape

Loo

kout

Vill

age

Ligh

thou

se$1

0,05

0,00

0.00

$1,0

18,0

00.0

0$1

3,12

6,00

0.00

N/A

$10,

626,

000.

00$7

4,00

0.00

$5,4

00.0

0

Kee

pers

Qua

rters

$112

,500

.00

$125

,000

.00

$1,0

86,0

00.0

0N

/A$3

11,0

00.0

0$4

2,50

0.00

$6,0

00.0

019

07 K

eepe

rs Q

uarte

rs$9

5,00

0.00

$78,

000.

00$6

56,0

00.0

0$4

35,0

00.0

0$1

99,0

00.0

0$3

7,00

0.00

$4,5

00.0

0Li

ve-S

avin

g St

atio

n$1

22,0

00.0

0$1

54,0

00.0

0$7

96,0

00.0

0$4

50,0

00.0

0$2

64,0

00.0

0$4

0,00

0.00

$7,8

00.0

0G

alle

y (C

oast

Gua

rd)

$70,

000.

00$2

5,00

0.00

$271

,000

.00

N/A

$81,

000.

00$2

2,00

0.00

$3,5

00.0

0O

'Boy

le B

ryan

t Hou

se$1

05,0

00.0

0$6

5,50

0.00

$301

,000

.00

$166

,000

.00

$127

,000

.00

$25,

000.

00$3

,400

.00

Gor

dan

Will

is H

ouse

$95,

000.

00$5

3,00

0.00

$251

,000

.00

$145

,000

.00

$111

,000

.00

$25,

000.

00$2

,400

.00

Jetty

Wor

kers

Hou

se 1

$95,

000.

00$9

1,00

0.00

$251

,000

.00

$183

,000

.00

$149

,000

.00

$25,

000.

00$2

,400

.00

Jetty

Wor

kers

Hou

se 2

$95,

000.

00$1

58,0

00.0

0$2

51,0

00.0

0$2

50,0

00.0

0$2

16,0

00.0

0$2

5,00

0.00

$2,4

00.0

0Po

rtsm

outh

Vill

age

Chu

rch

$234

,000

.00

$95,

000.

00$1

,111

,000

.00

$2,8

19,0

00.0

0$3

06,0

00.0

0$3

8,00

0.00

$6,0

00.0

0Sc

hool

$94,

500.

00$3

1,00

0.00

$397

,500

.00

$256

,000

.00

$98,

500.

00$3

3,50

0.00

$2,7

00.0

0Po

st O

ffice

$84,

500.

00$3

4,00

0.00

$374

,500

.00

$228

,000

.00

$95,

500.

00$3

3,50

0.00

$2,4

00.0

0Li

fesa

ving

Sta

tion

$320

,000

.00

$76,

000.

00$1

,611

,000

.00

$952

,000

.00

$273

,000

.00

$58,

000.

00$7

,200

.00

Sum

mer

Kitc

hen

(Liv

e-Sa

ving

Sta

tion)

$70,

000.

00$2

3,00

0.00

$165

,000

.00

$170

,000

.00

$86,

000.

00$2

4,00

0.00

$2,4

00.0

0

Was

hing

ton-

Rob

erts

Hou

se$1

25,5

00.0

0$6

7,00

0.00

$524

,500

.00

$302

,000

.00

$144

,500

.00

$33,

500.

00$3

,600

.00

Fran

k G

aski

ll H

ouse

$75,

000.

00$3

6,00

0.00

$321

,000

.00

$188

,000

.00

$104

,000

.00

$27,

000.

00$2

,400

.00

Hen

ry P

igot

t Hou

se$8

2,50

0.00

$63,

000.

00$3

66,0

00.0

0$2

95,5

00.0

0$1

33,0

00.0

0$3

3,50

0.00

$3,3

00.0

01 M

aint

enan

ce c

osts

wer

e es

timat

ed b

y C

ape

Look

out N

atio

nal S

eash

ore

cultu

ral r

esou

rce

man

agem

ent p

erso

nnel

. The

est

imat

ed c

osts

are

like

ly c

onse

rvat

ive

(act

ual c

osts

wou

ld li

kely

be

grea

ter d

ue to

tran

s-po

rtatio

n an

d lo

dgin

g re

quire

men

ts);

how

ever

, the

cos

ts w

ere

estim

ated

in a

con

sist

ently

acr

oss b

uild

ing

type

s (th

at is

, the

est

imat

es a

re re

liabl

e). T

he in

divi

dual

cha

rged

with

dev

elop

ing

the

cost

est

imat

es fi

rst

grou

ped

build

ings

bas

ed o

n ty

pe o

f stru

ctur

e, th

en c

onsu

lted

Nat

iona

l Par

k Se

rvic

e da

taba

ses (

Faci

lity

Man

agem

ent S

oftw

are

Syst

em, P

roje

ct M

anag

emen

t Inf

orm

atio

n Sy

stem

, Ass

et M

anag

emen

t Rep

ortin

g Sy

stem

, and

the

“Opt

imiz

er”)

and

use

d pr

ior k

now

ledg

e to

est

imat

e co

sts b

y bu

ildin

g, ty

pe, l

ocat

ion

(that

is, d

istri

cts h

ave

diffe

rent

dis

tanc

es to

Par

k H

eadq

uarte

rs) a

nd sq

uare

foot

age.

The

cos

t est

imat

ion

task

fo

r the

17

build

ings

took

roug

hly

20 h

ours

to c

ompl

ete.

Page 47: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Appendix 2. Value of Condition, Remaining Significance, and Use Potential for 17 Buildings Among Different Scenarios 37

Appendix 2. Value of Condition, Remaining Significance, and Use Potential for 17 Buildings Among Different Scenarios

In this appendix, the relative value for each historic building is presented by year for each scenario, with the relative value displayed in terms of the building’s condition, remaining significance, and use potential. In the Optimal Preservation (OptiPres) Model, we separate the historical significance attribute “condition” in this presentation because it is directly altered by the application of different actions. Condition has a weight of 0.17 within the historical significance score. The remaining signifi-cance includes three other components of historical significance: association to fundamental purpose, character, and national register (total weight 0.83 of historical significance). Historical significance accounts for 0.71 of relative value, and use potential accounts for 0.21 of relative value. The model dynamics for changes in conditions, remaining significance, and use potential by different adaptation actions are described in appendix 1, table 1.6.

Page 48: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

38 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Figure 2.1. Components of resource value under annual allocation of $50,000. Relative value is the weighted scores of utility for each building. [CLV, Cape Lookout Village; PV, Portsmouth Village]

Henry Pigott House PV

Lifesaving Station PV Summer Kitchen PV Washington−Roberts House PV Frank Gaskill House PV

Jetty Workers House 2 CLV Church PV School PV Post Office PV

Galley (Coast Guard CLV) O’Boyle Bryant House CLV Gordon Willis House CLV Jetty Workers House 1 CLV

Lighthouse CLV Keeper’s Quarters CLV 1907 Keeper’s Quarters CLV Lifesaving Station CLV

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

Year

Rela

tive

valu

e

Condition Remaining significance Use potential

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30

Page 49: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

Appendix 2. Value of Condition, Remaining Significance, and Use Potential for 17 Buildings Among Different Scenarios 39

Year

Rela

tive

valu

e

Condition Remaining significance Use potential

Henry Pigott House PV

Lifesaving Station PV Summer Kitchen PV Washington−Roberts House PV Frank Gaskill House PV

Jetty Workers House 2 CLV Church PV School PV Post Office PV

Galley (Coast Guard CLV) O’Boyle Bryant House CLV Gordon Willis House CLV Jetty Workers House 1 CLV

Lighthouse CLV Keeper’s Quarters CLV 1907 Keeper’s Quarters CLV Lifesaving Station CLV

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30

Figure 2.2. Components of resource value under annual allocation of $222,000. Relative value is the weighted scores of utility for each building. [CLV, Cape Lookout Village; PV, Portsmouth Village]

Page 50: ofr20181180.pdf - Optimizing Historical Preservation Under ... · Center ( through grant agreement G15AP00141. Additional funding for model development was provided by the National

40 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Year

Rela

tive

valu

e

Condition Remaining significance Use potential

Henry Pigott House PV

Lifesaving Station PV Summer Kitchen PV Washington−Roberts House PV Frank Gaskill House PV

Jetty Workers House 2 CLV Church PV School PV Post Office PV

Galley (Coast Guard CLV) O’Boyle Bryant House CLV Gordon Willis House CLV Jetty Workers House 1 CLV

Lighthouse CLV Keeper’s Quarters CLV 1907 Keeper’s Quarters CLV Lifesaving Station CLV

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30

Figure 2.3. Components of resource value under annual allocation of $500,000. Relative value is the weighted scores of utility for each building. [CLV, Cape Lookout Village; PV, Portsmouth Village]

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Appendix 2. Value of Condition, Remaining Significance, and Use Potential for 17 Buildings Among Different Scenarios 41

Year

Rela

tive

valu

e

Condition Remaining significance Use potential

Henry Pigott House PV

Lifesaving Station PV Summer Kitchen PV Washington−Roberts House PV Frank Gaskill House PV

Jetty Workers House 2 CLV Church PV School PV Post Office PV

Galley (Coast Guard CLV) O’Boyle Bryant House CLV Gordon Willis House CLV Jetty Workers House 1 CLV

Lighthouse CLV Keeper’s Quarters CLV 1907 Keeper’s Quarters CLV Lifesaving Station CLV

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30

Figure 2.4. Components of resource value under annual allocation of $70,000 with an additional $225,000 every 5 years. Relative value is the weighted scores of utility for each building. [CLV, Cape Lookout Village; PV, Portsmouth Village]

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42 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Year

Rela

tive

valu

e

Condition Remaining significance Use potential

Henry Pigott House PV

Lifesaving Station PV Summer Kitchen PV Washington−Roberts House PV Frank Gaskill House PV

Jetty Workers House 2 CLV Church PV School PV Post Office PV

Galley (Coast Guard CLV) O’Boyle Bryant House CLV Gordon Willis House CLV Jetty Workers House 1 CLV

Lighthouse CLV Keeper’s Quarters CLV 1907 Keeper’s Quarters CLV Lifesaving Station CLV

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30

Figure 2.5. Components of resource value under annual allocation of $222,000 with an additional $225,000 every 5 years. Relative value is the weighted scores of utility for each building. [CLV, Cape Lookout Village; PV, Portsmouth Village]

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Appendix 2. Value of Condition, Remaining Significance, and Use Potential for 17 Buildings Among Different Scenarios 43

Year

Rela

tive

valu

e

Condition Remaining significance Use potential

Henry Pigott House PV

Lifesaving Station PV Summer Kitchen PV Washington−Roberts House PV Frank Gaskill House PV

Jetty Workers House 2 CLV Church PV School PV Post Office PV

Galley (Coast Guard CLV) O’Boyle Bryant House CLV Gordon Willis House CLV Jetty Workers House 1 CLV

Lighthouse CLV Keeper’s Quarters CLV 1907 Keeper’s Quarters CLV Lifesaving Station CLV

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30

Figure 2.6. Components of resource value under annual allocation of $222,000 assuming no vulnerability. Relative value is the weighted scores of utility for each building. [CLV, Cape Lookout Village; PV, Portsmouth Village]

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44 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Year

Rela

tive

valu

e

Condition Remaining significance

Henry Pigott House PV

Lifesaving Station PV Summer Kitchen PV Washington−Roberts House PV Frank Gaskill House PV

Jetty Workers House 2 CLV Church PV School PV Post Office PV

Galley (Coast Guard CLV) O’Boyle Bryant House CLV Gordon Willis House CLV Jetty Workers House 1 CLV

Lighthouse CLV Keeper’s Quarters CLV 1907 Keeper’s Quarters CLV Lifesaving Station CLV

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0.0

0.2

0.4

0.6

0.8

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30 0 5 10 15 20 25 30

0 5 10 15 20 25 30

Figure 2.7. Components of resource value under annual allocation of $222,000 assuming no use potential. Relative value is the weighted scores of utility for each building. [CLV, Cape Lookout Village; PV, Portsmouth Village]

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Appendix 2. Value of Condition, Remaining Significance, and Use Potential for 17 Buildings Among Different Scenarios 45

Tota

l cos

t, in

thou

sand

s of

dol

lars

Accumulated value Total cost

Henry Pigott House PV

Lifesaving Station PV Summer Kitchen PV Washington−Roberts House PV Frank Gaskill House PV

Jetty Workers House 2 CLV Church PV School PV Post Office PV

Galley (Coast Guard CLV) O’Boyle Bryant House CLV Gordon Willis House CLV Jetty Workers House 1 CLV

Lighthouse CLV Keeper’s Quarters CLV 1907 Keeper’s Quarters CLV Lifesaving Station CLV

0

200

400

600

0

200

400

600

0

200

400

600

0

200

400

600

0

200

400

600

0

10

20

0

10

20

0

10

20

0

10

20

0

10

20

Accu

mul

ated

val

ue1: Annual allocation of $50,000.2: Annual allocation of $222,000.3: Annual allocation of $500,000.4: Annual allocation of $70,000 and an additional $225,000 every five years.5: Annual allocation of $222,000 every year and an additional $225,000 every fiveyears. 6: Annual allocation of $222,000 without consideration of vulnerability.7: Annual allocation of $222,000 every year without consideration of use potential.

1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7

1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7

1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7

1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7

1 2 3 4 5 6 7

Figure 2.8. Accumulated values and total costs of individual buildings predicted under each scenario. X-axis identifies the scenario. [CLV, Cape Lookout Village; PV, Portsmouth Village]

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46 Optimizing Historical Preservation—Overview of the OptiPres Model and Pilot Test at Cape Lookout National Seashore

Appendix 3. Computer Code for Optimal Preservation ModelTwo documents of computer code for the Optimal Preservation Model are available for download at

https://doi.org/10.3133/ofr20181180.

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For more information concerning the research in this report, contact:USGS National Climate Adaptation Science Center12201 Sunrise Valley Drive, Mail Stop 516Reston, VA [email protected]

For additional information, visit: https://casc.usgs.gov/Learn more about this and other Southeast Climate Adaptation Sci-

ence Center projects at:https://casc.usgs.gov/centers/southeast

Publishing support provided by the Reston and Rolla Publishing Service Centers

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Seekamp and others—

Optimizing Historical Preservation—

Overview of the OptiPres M

odel and Pilot Test at Cape Lookout National Seashore—

OFR 2018–1180ISSN 2331-1258 (online)https://doi.org/10.3133/ofr20181180


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