Date post: | 27-Mar-2015 |
Category: |
Documents |
Upload: | kylie-mckay |
View: | 213 times |
Download: | 0 times |
Woodburn Interchange EA
Evaluation Framework Presentation
SWG Meeting #2
April 10, 2003
Process Overview
Define the problem
Establish the evaluation framework
Identify new alternatives/options
Apply threshold screening of alternatives/ options for fatal flaws
Evaluate and rank alternatives
Select study alternatives/options
Establish The Evaluation Framework
Evaluation framework includes two types of criteria:
– Threshold screening of feasible from non-feasible alternatives
– Alternative evaluation of feasible alternatives
Identify Alternatives
Desired Outcome:
– All ideas are developed into alternatives/options with the best chance
– Check previously dismissed alternatives to validate cause for dismissal in light of changed conditions
– Define alternatives/options in such a way they can be directly compared one to another
Threshold Screening Process
Desired Outcome:
– Eliminate infeasible, unreasonable alternatives/options
– Spend resources evaluating alternatives/options that have realistic prospect of being implemented
Threshold Screening Criteria Should Be:
Thresholds --- either a project meets the criteria or it does not
Easily measured --- no substantial data gathering necessary
Non-judgemental --- not used to prejudge on criteria that require more analysis
Woodburn Threshold Criteria
Federal Policy– Satisfies 20-year design life
– Meets interstate design and access policies
– Consistent with local plans
– Local system improvements support interchange investment
Woodburn Threshold Criteria
State Policy– Supports safe movement of freight
– Satisfies defense highway design criteria
– Satisfies major investment policy hierarchy
– Meets access policy or can reasonably justify a deviation
Woodburn Threshold Criteria
Draft Local Project Criteria– Relatively similar impacts or distinct advantage
over another alternative
Threshold Screening Caution
In order to meet the schedule and budget commitments:
– Anytime a fatal flaws is discovered for an alternative…it is eliminated from further consideration
Alternative Evaluation Process
Desired Outcome: – Select alternatives/options for detailed
evaluation in the environmental document
Evaluation criteria should be:
Comprehensive -- reflect the full range of stakeholder values
Fundamental ---relate to topics that really matter Relevant ---help distinguish among alternatives Independent---don’t allow double-counting of
outcomes Measurable---allow for clear comparison of
alternatives Well-defined---mutual understanding of meaning
Woodburn Draft Evaluation Categories
Transportation & Safety
Natural Resources
Developed Environment
Implementation and Costs
Alternative evaluation process involves:
Developing criteria categories
Developing measurable criteria in each category
Rating alternatives
Weighting criteria
Calculating rankings
Evaluation criteria may be either:
Natural scales - easily understood measures ($, acres, number of structures)
Constructed scales - developed scales for less quantifiable measures (safety, bike/pedestrian connectivity)
Note: Criteria must reflect data availability and data collection budget constraints
Rating Alternatives
Based on data collected for each criteria
Developed by staff
Available for review and discussion by SWG
Alternatives will be rated for their performance against the criteria:
Alternative Safety # residentialdisplacements
A -1 Poor 6
A-2 Exceptional 12
A-3 Above Average 9
Evaluation Criteria will be weighted by the SWG to:
Represent the multiple values of stakeholders
Perform sensitivity analysis
Calculate and visually display the trade-offs
Evaluate Remaining Alternatives
Factual rating against performance measures
Value weighting to reflect trade-off in values
Single score for each competing alternative
Performance ValueCriterion Measure Rate x Weight = Score
A 3 20 60
B 4 70 280
C 1 10 10
D 2 25 50
Total Score 400
Rank Alternative
Highest score represents highest value
Scores are not “the answer” but provide a basis for informed discussion and justification of choices
Allows “apples to apples” comparison
Alternative Score
Alternative 1 (II-1/B-2a/b) 86.6
Alternative 2 (II-1/B-2c/d) 76.9
Alternative 3 (II-1/A--1d) 65.4
Alternative 4 (II-1/A-1e) 64.3
Alternative 5 (II-4/B-2a/B) 63.4
Alternative 6 (II-3/B-2a/b) 60.7
Alternative 7 (II-4/B-2c/d) 52.5
Alternative 8 (II-3/B-2c/d) 52.0
Alternative 9 (II-4/A-1d) 42.6
Alternative 10 (II-4/A-1e) 40.6
Alternative 11 (II-3/A-1d) 40.1
Alternative 12 (II-3/A-1e) 39.5
Alternative 13 (III-2/B-2c/d) 37.3
Alternative 14 (III-2/B-2a/b) 36.8
Alternative 15 (III-2/B-3a) 35.1
Alternative 16 (III-1/B-2a/b) 31.8
Alternative 17 (III-2/B-3d) 28.6
Alternative 18 (III-1/B-3a) 28.5
Alternative 19 (III-1/B-2c/d) 27.3
Alternative 20 (III-1/B-3d) 23.2
Project Alternatives
Sensitivity analysis will indicate:
If a criterion has an influence on the results and how much
What change is required in the weight to produce a change in the results
Sensitivity Analysis -- Contribution by Criteria
0.89
0.710.64
0.620.58
0.44
0.360.33 0.32 0.32
Alternate 5 Alternate 1 Alternate 7 Alternate 6 Alternate 10 Alternate 2 Alternate 3 Alternate 9 Alternate 8 Alternate 4
Right-of-Way ImpactsNatural Environment ImpactsCommunity Livability ImpactsTransportation PerformanceCost
Criteria Legend
Evaluation Framework Summary
Well defined and structured criteria will:– Provide a good basis for rating alternatives
– Provide the basis for weighting criteria
– Provide a focus for discussing community values rather than positions on particular alternatives
– Provide the information for decision-making