KINGS HIGHWAY UPGRADE NELLIGEN BRIDGE · 3 THE PROPOSAL 17 3.1 Proposal Design 18 4 URBAN DESIGN...

KINGS HIGHWAY UPGRADENELLIGEN BRIDGE

URBAN DESIGN REPORT AND LANDSCAPE CHARACTER AND VISUAL IMPACT ASSESSMENT

AUGUST 2016

ii KINGS HIGHWAY UPGRADE | NELLIGEN BRIDGE | URBAN DESIGN REPORT AND LANDSCAPE CHARACTER AND VISUAL IMPACT ASSESSMENT

iii

KINGS HIGHWAY UPGRADENELLIGEN BRIDGE

URBAN DESIGN REPORT AND LANDSCAPE CHARACTER AND VISUAL IMPACT ASSESSMENT

AUGUST 2016

Prepared by

PO Box 880 Darlinghurst, NSW 1300 P (02) 9361 4549 • F (02) 9361 4569 www.sm2group.com.au ABN 65 065 578 985

Revision Status Date Released byA Preliminary Draft - For Review 17.06.16 MWB Preliminary Draft 21.06.16 MWC Final 08.07.16 MWD Final - Revised 11.07.16 MWE Final - Revised 01.08.16 MWF Final - Revised 29.08.16 MW

Prepared for

iv KINGS HIGHWAY UPGRADE | NELLIGEN BRIDGE | URBAN DESIGN REPORT AND LANDSCAPE CHARACTER AND VISUAL IMPACT ASSESSMENT

EXECUTIVE SUMMARY 1

1 INTRODUCTION 31.1 Proposal Overview 4

2 THE EXISTING CONTEXT 52.1 Overview 6

2.2 The Proposal 7

2.3 Climate 8

2.4 Landform & Geology 9

2.5 Hydrology & Drainage 10

2.6 Open space, parks, and reserves 11

2.7 land use & zoning 12

2.8 Road, cycleway & pedestrian facilities 14

2.9 Heritage & Existing Structures 15

2.10 site ecology 16

3 THE PROPOSAL 173.1 Proposal Design 18

4 URBAN DESIGN STRATEGY 194.1 Strategy Overview 20

4.2 Urban Design Objectives & Principles 20

4.3 Urban Design Elements 22

4.4 Urban Design and Landscape Strategy Plan 29

5 LANDSCAPE DESIGN STRATEGY 335.1 Landscape Design Approach 34

5.2 Urban Design & Landscape Concept Plan 35

6 LANDSCAPE CHARACTER ASSESSMENT 416.1 Overview 42

6.2 Landscape Character Zones 43

6.3 Landscape Character Zone Impact Summary 49

7 VISUAL IMPACT ASSESSMENT 517.1 Overview 52

7.2 Visual Catchment Zones 53

7.3 Viewpoint Assessment Methodology 54

7.4 Primary Visual Catchment Zone 55

7.5 Secondary Visual Catchment Zone 57

7.6 Road User Views 59

7.7 Summary of Visual Impacts 60

7.8 landscape PHOTOMONTAGES 61

8 MITIGATION MEASURES & CONCLUSIONS 678.1 Overview 68

8.2 Mitigation Measures 68

8.3 Conclusion 68

CONTENTS

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Figure 2.1: Regional context with the proposal highlighted in RED 6

Figure 2.2: Local context with the proposal 7

Figure 2.3: Topography in the proposal and surrounding context 9

Figure 2.4: Creeks, waterways and overland flow paths in the region 10

Figure 2.5: Open space surrounding the proposal 11

Figure 2.6: Land use and zoning in the Nelligen region 12

Figure 2.7: Local zoning and land use patterns 13

Figure 2.8: Local road network 14

Figure 2.9: Local sites of heritage value 15

Figure 2.10 Local vegetation communities 16

Figure 4.1: Urban design elements organisational chart 23

Figure 4.2: Proposed Nelligen Bridge alignment 27

Figure 4.3: Section A-A typical cross section at western end of proposed bridge 27

Figure 4.4: Section B-B typical cross section at centre of proposed bridge 27

Figure 4.5: Section C-C typical cross section at eastern end of proposed bridge 27

Figure 4.6: Urban design and landscape strategy key plan 29

Figure 4.7: Urban design and landscape strategy plan (1 of 3) 30



Figure 5.1: Concept key plan 35

Figure 5.2: Urban design and landscape concept plan (1 of 3) 36



Figure 5.5: Typical cross section showing new embankment at eastern abutment of proposed bridge 39

Figure 5.9: Typical cross section showing modified exposed rock cutting below Ferry Master’s Residence 39

Figure 6.1: Landscape character zones 43

Figure 6.2: Landscape character zone 1 extent 44





Figure 7.1: Visual Catchment Zones 53

Figure 7.2: Primary Visual Catchment Zone 54

Figure 7.3: Secondary Visual Catchment Zone 57

LIST OF FIGURES

Table 4.1: Urban design objectives and principles 21

Table 4.2: Recommendations for cuttings 24

Table 4.3: Recommendations for embankments 25

Table 4.4: Recommendations for retaining walls 25

Table 4.5: Recommendations for the bridge 26

Table 4.6: Recommendations for roadside furniture elements 28

Table 5.1: Revegetation urban design principles 34

Table 5.2: Revegetation methods 34

Table 5.3: Revegetation communities 41

Table 6.1: Roads and Maritime Impact grading matrix 44

Table 6.2: Landscape character zone 1 impact assessment 46





Table 6.7: Landscape character zones impact summary 51

Table 7.1: Roads and Maritime Impact grading matrix 54

Table 7.2: Primary Visual Catchment Zone impact assessment 58

Table 7.3: Secondary Visual Catchment Zone impact assessment 60

Table 7.4: Visual Impact Assessment Summary 62

Table 8.1: Summary of mitigation measures 69

LIST OF TABLES

vi KINGS HIGHWAY UPGRADE | NELLIGEN BRIDGE | URBAN DESIGN REPORT AND LANDSCAPE CHARACTER AND VISUAL IMPACT ASSESSMENT

LIST OF PLATES

Plate 1.1: Looking west over the Clyde River towards Nelligen 4

Plate 2.1: View across the Clyde River under Nelligen Bridge 7

Plate 2.2: View northwest towards Nelligen from Ferry Master’s Residence 8

Plate 2.3: Typical temperate coastal vegetation associated with Nelligen region 8

Plate 2.4: Steep terrain as viewed from Nelligen Bridge 9

Plate 2.5: Nelligen village centre from Soldier’s Memorial 12

Plate 2.6: Circulation infrastructure on Nelligen Bridge 11

Plate 4.1: Exposed rock cutting under Ferry Master’s Residence 22

Plate 4.2: Exposed rock cutting at Maisies Lane 22

Plate 4.3: Shoreline downriver from existing bridge, eastern side 23

Plate 4.4: Shoreline downriver from existing bridge, western side 23

Plate 4.5: Sloped cutting in rock 24

Plate 4.6: Partially revegetated steep cutting 24

Plate 4.7: Aggregate embedded into wall panel units selected to match the local geology 24

Plate 4.8: Existing bridge from western shore of the Clyde River 26

Plate 4.9: Existing bridge from eastern shore of the Clyde River 26

Plate 5.1: Example of bushland with a diverse understory 47

Plate 6.1: Landscape character zone 1 character images 46





Plate 7.1: Eastern tie-in 61

Plate 7.2: Western tie-in 61

Plate 7.3: Existing view from Viewpoint #3: Ferry Master’s Residence looking west over the Clyde River 62

Plate 7.4: Proposed view from Viewpoint #3: Ferry Master’s Residence looking west over the Clyde River 63

Plate 7.5: Existing view from Viewpoint #4: Wharf Street looking east along the southern edge of the existing bridge 64

Plate 7.6: Proposed view from Viewpoint #4: Wharf Street looking east along the southern edge of the existing bridge 65

1

Introduction

This Urban Design Report and Landscape Character and Visual Impact Assessment has been prepared for Roads and Maritime Services (Roads and Maritime) of New South Wales (NSW), by Spackman Mossop Michaels (SMM) as part of the Review of Environmental Factors (REF) for the proposed upgrade of the Kings Highway at Nelligen. This proposed highway upgrade (the proposal) has been developed in response to an identified need for improvement to the existing bridge condition and associated road alignment in order to improve road user safety.

Existing Context

The proposal covers a section of the Kings Highway about 7.5 kilometres west of Batemans Bay along the Clyde River at the village of Nelligen. The Kings Highway is the major east-west route connecting Eurobodalla Shire to the Australian Capital Territory (ACT) border, connecting Canberra to Batemans Bay and the Princes Highway. A number of regional urban centres lie along the Highway, including Braidwood, Bungendore, and Queanbeyan (refer Figure 2.1). In the local context, the site falls within a 400 metre buffer around the existing Nelligen Bridge.

The construction of a new bridge at Nelligen and the associated roadworks have been determined as necessary for the long term sustainable growth of the South Coast region. The existing bridge piles have deteriorated and require significant repairs or replacement. Furthermore, the current approach experiences a high crash rate. The preferred option would replace the bridge with a new structure north of the existing crossing. This proposal provides a cost-effective, long-term solution which has fewer impacts on private property and heritage structures in Nelligen. The proposal seeks to achieve a level of safety, service, and ride quality for residents, businesses, and industry along the Kings Highway; currently, the road in the vicinity of the bridge experiences a higher than average crash rate. Other key objectives for the proposal include improving the driving experience of local residents, tourists, and east-west freight.

Refer Section 2 for a detailed study of existing context and Section 6 for a detailed assessment of landscape character impacts.

EXECUTIVE SUMMARY

The Proposal

Roads and Maritime proposes to build a new bridge at Nelligen and remove the existing structure in order to ensure a long term Kings Highway crossing of the Clyde River is retained at Nelligen and to improve road safety.

The proposal includes building a bridge spanning about 325 metres, improving the curve on approach to the bridge from the east, and shoulder widening on the existing Kings Highway. The main features of the proposal include: • construction of a new 325 metre long bridge to the north of the existing

bridge over the Clyde River, consisting of: ¬ one 3.5 metre wide traffic lane in each direction

¬ one 2.5 metre wide shoulder in each direction

¬ one 2 metre wide shared path on the southern side of the bridge

• adjustments to the Kings Highway on both the eastern and western banks of the Clyde River to meet the new bridge alignment, including new abutments, fill batters, and retaining walls

• intersection improvements at the intersections of the Kings Highway with Bridge View Road and Old Nelligen Road.

• road widenings at the intersection of the Kings Highway at Bridge View Road• closure, removal, and revegetation of Thule Road at its current northern

intersection with the Kings Highway.• demolition and removal of the existing bridge

Urban Design Strategy

The over-arching aim of the urban design strategy is to ensure that the proposal is physically and visually integrated with its surrounding environment, reduces visual impact and where possible, maximises engagement of the road user in a local context to provide a more enjoyable and interesting driving experience. The proposal would demonstrate consistency with other nearby sections of the Kings Highway and would minimise impacts on the natural and cultural environment.

The urban design strategy also considers local resident requirements such as maintaining the semi-rural character of the place and mitigating visual impacts.

Bridges, retaining walls, cut and fill, drainage and water quality structures and fencing are all considered as part of the strategy.

Refer Section 4 for key urban design strategies and Section 7 for a detailed assessment of visual impacts..

Landscape Design Strategy

The landscape design strategy outlines landscape methodologies for establishing vegetation into the proposal. These methodologies comprise planting and seeding methodologies aimed at producing a cost-effective and rapidly establishing revegetation outcome. A combination of methods is required to accommodate the various construction zones and to work within local endemic vegetation communities.

The general approach to the landscape design is to provide a well-vegetated road corridor that aims to integrate the highway with the surrounding landscape and provide motorists with a sense of place along the highway journey. In order to achieve this, the landscape revegetation must strike a balance between screening the highway from the sensitive views from surrounding areas and maintaining key views from the highway to the surrounding landscape.

The planting and revegetation design also aims to minimise the potential ecological impacts of the proposal by stabilising earthworks to prevent erosion, and reinforce existing habitats and ecological corridors through endemic species selection.

Refer Section 5 for key landscape design strategies and Section 8 for visual impact mitigation measures.

2 KINGS HIGHWAY UPGRADE | NELLIGEN BRIDGE | URBAN DESIGN REPORT AND LANDSCAPE CHARACTER AND VISUAL IMPACT ASSESSMENT

Landscape Character Assessment

Following field and desktop studies, the proposal study area has been divided into five Landscape Character Zones (LCZ). The zones have been defined through gaining an understanding of land use, topography, and vegetation in combination with other factors intrinsic to the local landscape. The five landscape character zones are: • LCZ1 - Nelligen Village• LCZ2 - Estuarine Wetlands• LCZ3 - Clyde River Valley• LCZ4 - Floodplain Swamp Forest• LCZ5 - Batemans Bay Cycad Forest.

Overall, the proposal would have an impact on landscape character. While the works, would partially take place in an established road corridor, they would impact on all LCZs to some degree.

From the perspective of local property owners, tourists, motorists, river users and cyclists landscape character would be impacted, particularly in highly visible areas adjacent to the Clyde River. The overall character impacts in each LCZ are summarised below.

LCZ SENSITIVITY MAGNITUDELANDSCAPE CHARACTER

IMPACT

LCZ 1: Nelligen Village High Moderate Moderate to High

LCZ 2: Estuarine Wetlands High Moderate Moderate to High

LCZ 3: Clyde River Valley Moderate Moderate Moderate

LCZ 4: Floodplain Swamp Forest Moderate Moderate Moderate

LCZ 5: Batemans Bay Cycad Forest Moderate Low Moderate to Low

Refer Section 6 for Landscape Character Assessment detailed analysis and results.

Visual Impact Assessment

The potential visual impact of the proposal has been assessed in relation to a number of key and potential viewpoints within a defined visual catchment area. The study area has then been defined into two Visual Catchment Zones (VCZ) based on geographic proximity to the proposal which are: • Primary VCZ approximately 0 - 200 metres. • Secondary VCZ approximately 200 - 400 metres.

Overall, the proposal would have an impact on views in and around the study area. While the works, for the most part, are to take place in an established road corridor, they would impact on all Visual Catchment Zones (VCZ) to some degree, with the greatest impact being on the road user within the Primary VCZ. The overall visual impacts in each VCZ are summarised below.

VCZ # SENSITIVITY MAGNITUDE VISUAL IMPACT

Primary Zone: 0-200 m

1 Moderate Moderate Moderate


3 Moderate Low Moderate to Low

4 High High High


Secondary Zone: 200m-400m




9 Low Low Low

Refer Section 7 for Visual Impact Assessment detailed analysis and results.

Conclusion

The visual qualities of the proposal are important in the local context, especially as this is the only location where the Kings Highway passes over the Clyde River. The landscape would be easily viewed from multiple perspectives locals and tourists alike, including drivers, boaters, and residents of Nelligen village.

The urban design and landscape principals and objectives that have been developed for the proposal take into consideration the existing landscape character and scenic qualities of the area. Mitigation measures and landscape treatments have been derived from these objectives in order to develop a strategy for reducing visual impacts.

The overall visual impacts would be moderate to low depending on the distance from which the proposal is viewed. However some of these long-range views may also require impact mitigation. Specifically, views of the bridge and associated roadworks from viewpoints adjacent to the Clyde River have the potential to be impacted by new landforms and vegetation removal. Localised treatments, including revegetation, would mitigate any visual impacts.

The proposal fulfils the identified urban design objectives and principles, when assessed in combination with the proposed mitigation measures.

Refer Section 8 for a detailed summary of conclusions.

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1 INTRODUCTION

1.1 Proposal Overview 4


1.1 PROPOSAL OVERVIEW

1.1.1 BACKGROUND

This Urban Design Report and Landscape Character and Visual Impact Assessment has been prepared for Roads and Maritime Services of New South Wales (NSW) as part of the Review of Environmental Factors (REF) for the proposed realignment of the Kings Highway at Nelligen. This proposed highway realignment (the proposal) has the following objectives:• Provide a safe and reliable road crossing of the Clyde River at Nelligen without

load or speed restrictions within the next ten years.• Provide a safer road environment on the bridge approaches that reduces the

frequency and severity of crashes to below the class average.• Eliminate the ongoing asset issues associated with the existing bridge.• Support efficient freight movements without load or speed restrictions within

the next ten years by building a new bridge that caters for HML B-doubles.• Provide a safer crossing the Clyde River for pedestrians and cyclists.

The report has been prepared in accordance with the Roads and Maritime document Guidelines for Landscape Character and Visual Impact Assessment and describes:• the landscape character of the existing site and its surrounds• a landscape contextual analysis• the sensitivity of the landscape character to the proposal• the potential impacts on landscape character• the significance and sensitivity of existing views into and out of the study area• the potential visual impacts caused by the proposal• preliminary urban design recommendations, which are to be addressed as the

design is developed to improve the design outcome for motorists and local residents, as well as avoiding and mitigating visual impacts

• recommendations, which in conjunction with the REF document, aim to minimise impacts on the natural environment and describe how to revegetate the work.

1.1.2 STUDY METHOD

The undertaking of the landscape character and visual impact assessment along with the finalisation of the concept design has been an iterative process. This has enabled the concept design to be refined throughout the development process, thereby reducing and mitigating the potential landscape character and visual impact wherever possible to preserve the aesthetic quality of the Clyde River valley (refer Plate 1.1).

The method used to undertake this study is summarised as follows:• undertaking an initial site visit and field investigation, reviewing relevant

literature, analysing aerial photographs and topographic maps to understand the study area

• reviewing the initial engineering concept design and supporting material to gain an appreciation of the proposal

• defining landscape character through a contextual analysis• identifying and describing LCZs and evaluating the impact of the proposal on

these zones• identifying the visual catchment of the proposal• selecting viewpoints within the visual catchment representing the range of

different land uses in the proposal area• evaluating visual impact of the proposal by comparing the sensitivity of

viewpoints and the magnitude of the impact of the proposal upon them• identifying urban design and landscape opportunities, as well as methods for

mitigating adverse visual impacts, to be consideration during the detail design phase.

Plate 1.1: Looking west over the Clyde River towards Nelligen BridgeSource: SMM

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2.1 Overview 6

2.2 The Proposal 7

2.3 Climate 8

2.4 Landform & Geology 9

2.5 Hydrology & Drainage 10

2.6 Open Space, Parks, and Reserves 11

2.7 Land Use & Zoning 12

2.8 Road, Cycleway & Pedestrian Facilities 14

2.9 Heritage & Existing Structures 15

2.10 Site Ecology 16

2 THE EXISTING CONTEXT


Nelligen Bridge carries a single lane of traffic in each direction (3.6 and 3.8 metres wide) with no marked shoulders. It forms part of the Kings Highway which is the major east-west route connecting Eurobodalla Shire with major inter and intra state routes. The highway starts at the Australian Capital Territory (ACT) border and joins the Princes Highway at Batemans Bay about 170km to the east. While the freight movements on the Kings Highway are a smaller proportion of all vehicles when compared with some other key routes, the route is significant as there are limited alternative east-west routes.

The highway is strategically important in supporting sustainable regional growth on the south coast. The corridor and bridge play important transport roles, including regional tourism, particularly for Canberra and Queanbeyan residents travelling to and from the south coast, regional access for people living on, and in, the vicinity of the corridor as their only east–west link to access services located predominantly in Canberra and Queanbeyan and as an east-west freight route. Murrays operates a private bus service between Canberra and the South Coast that makes a stop at the Steampacket Hotel. In addition, Priors runs a school bus service that also stops at Nelligen.

2.1 OVERVIEW

Figure 2.1: Regional context with the proposal highlighted in RED

Source: base map Google Earth Maps, additional data from AURIN artwork: SMM

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Plate 2.1: View across the Clyde River under Nelligen Bridge

2.2 THE PROPOSAL

The primary objective of this proposal is the construction of a new 325 metre bridge to carry the Kings Highway over the Clyde River at Nelligen. Key features of this proposal include: Demolition of existing bridge following opening of new bridge, which would include:• one 3.5 metre wide traffic lane in each direction• one 2.5 metre wide shoulder in each direction• two metre wide pedestrian path on the southern side of the bridge• adjustments to the Kings Highway on both the eastern and western sides of

the river to meet the new bridge alignment, including the widening of the curve on the western side to current standards

• Provision of a new intersection at Maisies Lane on the realigned Kings Highway to provide access to the Nelligen township

• upgrade of the intersection at Bridge View Road• improve sightline distances at Old Nelligen Road.

Figure 2.2: Local context with the proposalSource: SMM

Source: Base map Department of Lands; additional base data provided by RMS; artwork: SMM


The village of Nelligen is located in southeastern coastal New South Wales, about 7.5 kilometres inland from Batemans Bay along the banks of the Clyde River. Nelligen experiences a temperate oceanic climate moderated by the village’s close proximity to the sea. The climate for this region is typified by warm summers and cool, sunny winters. Severe thunderstorms are not uncommon, with rainfall most prevalent in the summer months between November and March. However, the region experiences about 87 days of clear sun annually, mainly in the winter months.

Summer conditions in Nelligen span from November to March. The daily average maximum ranges between 22.9 °C and 25.8 °C, while nighttime lows can reach 12.2 °C to 13.9 °C. Thunderstorms originating over the Tasman Sea are a common occurrence during summer months, with November recorded as being the most cloudy month of the year.

Winter in Nelligen typically falls between April and October. The daily average maximum during these months ranges from 17.0 °C to 22.2 °C, whereas the average minimum temperatures range from 3.7 °C to 10.6 °C. August is recorded as the sunniest month of the year on average with about 10.5 days of clear weather.

Design Considerations • Priority would be given to endemic vegetation and species that are

accustomed to the temperate coastal conditions.

Refer to Section 2.10 of this report for more detailed information regarding existing vegetation.

2.3 CLIMATE

Plate 2.2: View northwest towards Nelligen from Ferry Master’s Residence

Source: SMM

Source: NSW National Parks

Plate 2.3: Typical temperate vegetation associated with the Nelligen region

Batemans Bay Cycad Forest vegetation community

The town of Nelligen situated amongst the low rolling hills of the South Coast

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2.4 LANDFORM & GEOLOGY

The study area is located on the Clyde River in the South Coast region of New South Wales. The regional landscape character is representative of the lower reaches of the Clyde River and its associated floodplain. The topography is typically flat adjacent Nelligen Creek and Clyde River with steeply undulating landforms beyond the immediate floodplain, including occasional outcrops and ridgelines.

Heading west on the Kings Highway over the Clyde River, the highway traverses the floodplains of Nelligen Creek which slowly ascends to steeper topography through Currowan State Forest. To the east lie forested slopes associated with the Benandarah State Forest which separates the proposal study area from the plains of the Monaro grazing districts on the coast (refer Plate 2.3).

Design Considerations• In cuttings, batter slopes would need to consider the existing underlying

geology. • Landform modifications would integrate where possible with natural terrain,

particularly from any possible long-range viewpoints.

Figure 2.3: Topography in the proposal and surrounding contextPlate 2.4: Steep terrain as viewed from Nelligen Bridge

Source: SMM

Source: Base map Department of Lands; additional base data provided by AURIN; artwork: SMM


Figure 2.4: Creeks, waterways and overland flow paths in the region

2.5 HYDROLOGY & DRAINAGE

The Clyde River at Nelligen is a valley estuary system that flows into the Tasman Sea. The mouth of the river is located to the east of Batemans Bay at the Tollgate Islands. Within the study area the Clyde River is tidally influenced and forms part of the Clyde Catchment. Several minor tributaries flow into the Clyde River within or near the study area, including Nelligen Creek to the north-west, Sheep Station Creek to the south-east, and Cyne Mallowes Creek in the north-east.

There are oyster farms within the river catchment downstream between Batemans Bay and Nelligen and the river has been recorded as having a notably low energy, with flushing times of between 19 to 24 days under purely tidal conditions. Historically, the region experienced one of its most severe floods in 1860 when the river was three metres above the high-tide mark. A heavy flood in 1898 also threatened low-lying buildings in Nelligen. Major floods also occurred in 1925 and 1934, and in the 1970s. It was reported that the bridge was not inundated by flood waters during this event and Council has advised that anecdotally the highest maximum observed flood height was 5.4 metres Australian Height Datum (AHD). As such, the existing bridge would have likely been designed to achieve the relevant flood immunity levels requirements of the 1960s, and it is understood that the main deck is located above the highest astronomical tide (king tide). The existing flood planning level implemented for the area of Nelligen is 5.9 metres AHD which exceeds the highest observed flood level.

The bridge currently drains directly to the river via scuppers. There is no road drainage infrastructure along the approaches to the bridge and road runoff can therefore drain unattenuated to the river. Any major spillage could pollute and impact the water quality and affect sensitive aquatic and riparian receptors within the river catchment.

Design Considerations• The proposed bridge span would provide the required level of flood immunity. • New drainage facilities would work with natural drainage patterns across the

landscape and provide protection to natural systems.


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2.6 OPEN SPACE, PARKS, AND RESERVES

The study area is dominated by extensive areas of connected native vegetation including the Clyde River National Park and a number of State Forests. The native vegetation frames the river corridor and provides a sense of enclosure. Further afield lies largely undeveloped areas which comprise of significant areas of national park and state forest including: Clyde River National Park, Murramarang National Park, Currowan State Forest, Bolaro State Forest, and Mogo State Forest which typically spread across steeper and upper slopes surrounding the study area. The proposal is most visible from the parklands at the Nelligen foreshore, which includes public open space, amenities, and interpretive signage describing the regional history.

Design Considerations

• The combination of the natural and cultural scenic qualities with local heritage values establishes a unique identity to the area. These values have a special meaning and provide a sense of place for the local inhabitants, as well as visitors and through traffic.

• With tourism being a substantial growth industry associated with the conservation areas in the LGA, the natural character of the Clyde River valley would be preserved as a touristic resource.

• The foreshore park is a highly valued area of open space which would require design consideration to assimilate the existing bridge abutments and approach roads into the waterfront open space.

Figure 2.5: Open space in the proposal and surrounding context



2.7 LAND USE & ZONING

The Clyde River is used both recreationally and by tourists for activities including boating, cruises, kayaking, fishing, water skiing and swimming. During the peak summer season daily boat trips (Merinda Cruises) run between Nelligen and Batemans Bay. The river is also used by houseboats (Clyde River Houseboats) and the Nelligen Yacht Club. There are six boat moorings located on the downstream side of the bridge close to the eastern shoreline. The existing moorings are held via a licence agreement or similar to occupy an allocated space, with the location of allocated space determined by Maritime Division of Roads and Maritime, in consultation with the licence holder.

Figure 2.6: Landuse and zoning in the Nelligen region

Source: base map Google Earth Maps, additional data from AURIN and the LPI artwork: SMM.Plate 2.5: Nelligen Village centre from the Soldier’s Memorial

Source: SMM

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The land use zoning within the study area, which can be broadly divided between the rural settlement of Nelligen on the western shore of the Clyde River and undeveloped and rural land, with some limited residential properties, on the eastern shore of the river. The main land use in the study area is Nelligen Village. It primarily comprises residential properties and a number of commercial buildings (ie. the guest house, café, nursery, general store). It also contains a wharf and boat ramp, which are located on the waterfront at the end of Wharf Street.

The local zoning on the western shore at Nelligen can be characterised by the following classifications:• Public recreation land: located along the waterfront and off Wharf Street. • Environmental conservation land: comprising sections of the waterfront, areas

of native vegetation within the heart of the village, and SEPP 14 designated wetlands north of the Kings Highway on the western side of the Clyde River.

While the zoning on the eastern shore is as follows:• Public recreation land: comprising a small park immediately south of the bridge

located on Thule Road. • Environmental living land: comprising residential housing and the Sunlit Waters

Leisure Retreat. • Environmental conservation land: comprising areas of remnant native

vegetation along the eastern shoreline, SEPP14 designated wetlands north of Kings Highway on the eastern side of the Clyde River, and the western limit of the Benandarah State Forest.

Design Considerations

• There is considerable open natural space in the region, and Eurobodalla Shire more broadly. The proposed works would improve the visibility and experience of the natural open space that is characteristic of this area.

• There is potential to degazette the existing bridge approach roads and reserves and incorporate into the existing public recreation land.

Figure 2.7: Local zoning and land use patterns



Circulation Network

There is a 1.4 metre wide unprotected pedestrian footpath on the south / downstream side of the bridge. There are no connecting pedestrian provisions either side of the bridge other than a short section of footpath on the eastern approaches linking into Thule Road, eventually giving way to a grass verge. Pedestrian and cyclist counts are not available however incidental observations made by Roads and Maritime, report volumes as being generally low, peaking during the summer months.

Design Considerations• Footpath additions on the eastern and western sides of the proposed bridge

would facilitate ease of movement across the Clyde River.

2.8 ROAD, CYCLEWAY & PEDESTRIAN FACILITIES

Figure 2.8: Local road network


Plate 2.6: Circulation infrastructure on Nelligen Bridge

Source: SMM

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2.9 HERITAGE & EXISTING STRUCTURES

Aboriginal Heritage

An Aboriginal Cultural Heritage Assessment for the Nelligen Bridge Replacement has been conducted by Umwelt Australia Pty Limited (Umwelt) on behalf of RMS. Predictive modelling of the archeaological context of the study area anticipates low density artefact scatters within a 5 kilmetre radius, most commonly associated with ridges, ridge crests and ridge slopes. Following an archaeological survey, one arteface scatter was found which contained a low density of artefacts with low archaeological assessment and low research potential, and moderate cultural significance. Two trees on the western side of the Clyde River to the north of the Kings Highway were identified as potential burial marker trees by the Batemans Bay Local Aboriginal Land Council. These trees are outside the proposal footprint and would be protected during construction.

Non-Aboriginal Heritage

Nelligen was historically a busy trade and commercial centre, linking the coast to the Southern Tablelands. European explorers and settlers reached the Batemans Bay area in the early 19th century, and progressive land grants were provided for the development of timber and fishing industries. Gold mining also took place in forested areas surrounding Nelligen village in the late 1800s. The historic legacy of Nelligen means the village contains a number of surviving historic buildings that define its character. As a historic settlement on the Kings Highway which was established to support the timber trade and gold mining, it now has an established tourism industry. These historical features are identified under the Standard Instrument Local Environmental Plan (SILEP) as worthy of heritage conservation.

Existing Structures

The existing road and bridge are unlit. There are no drainage provisions along the highway with the existing bridge draining directly to the Clyde River via scuppers. A submarine power cable runs under the Clyde River adjacent to the bridge on the downstream side. Two distribution power poles are located either side of the river. These connect the submarine cable to the above ground power lines that run into Nelligen and along Thule Road respectively.

Design Considerations• Aboriginal and non-Aboriginal cultural sites would be left undisturbed

wherever possible, in particular the two possible burial marker trees.• Remnant rural structures and vistas to and between these structures and

visual connections would be maintained wherever possible.Figure 2.9: Local sites of heritage value



2.10 SITE ECOLOGY

Vegetation Communities

Remnant and regrowth native vegetation in the area includes Batemans Bay Cycad Forest and Murramarang-Bega Lowlands Forest on the eastern shore. Extensive areas of vegetation (consistent with South Coast River Flat Forest) have been cleared for rural land use to the north, leaving only remnant patches. There are narrow bands of mangroves and intertidal native plant communities including Seagrass Meadows on the banks of the Clyde River. The western extent of the study area falls within a wildlife corridor mapped in the South Coast Regional Conservation Plan. Three threatened ecological communities have been identified in the study area: • Swamp Oak Floodplain Forest (TSC Act)• River Flat Eucalypt Forest (TSC Act)• Coastal Saltmarsh (TSC and EPBC Act).

Design Considerations• Existing vegetation communities would inform revegetation for the proposal

during detail design stage. • Bushland revegetation techniques utilising seed infused site topsoil should be

considered for use in off-line and densely vegetated sections of the proposal. • The management of weed species should be incorporated into the design,

construction, and operation of the new bridge project.

Figure 2.10: Local vegetation communities


17

3.1 Proposal Design 18

3 THE PROPOSAL


3.1 PROPOSAL DESIGN

3.10.1 ROAD DESIGN PARAMETERS

The proposal design parameters include the following: • speed limit: 80 km/h in each direction• number of lanes: one lane in each direction would be adequate to cater for

forecast traffic volumes, including widened paved shoulders• lane width: 3.5 metres• shoulder width: 2.5 metres• road surface type: flexible gravel pavement comprised of base and sub-base

with a sealed wearing course. Where the existing pavement is being reused, an asphalt overlay shall be applied to tie into the existing road.

3.10.2 ROAD SPACE ALLOCATION

The proposed design consists of a single carriageway and one lane in each direction. The highway geometry on both the eastern and western side of the Clyde River has been reconfigured to meet the new bridge alignment. Road widening of the existing highway on both sides of the Clyde River is also proposed.

BRIDGE

The proposal includes the demolition of the existing Nelligen Bridge and the construction of a new bridge, including associated highway realignment and local road improvements. The bridge abutments on the eastern and western banks of the river would shift to the north by 55 metres and 29 metres respectively. Indicative concept design details and an elevation diagram are included in Section 4.0.

The key features of the proposed bridge would include:• Bridge clearance of between 6.5 metres and 9.2 metres over the river below.• A bridge deck 15.4 metres wide to accommodate two lanes (3.5 metres

wide, two road shoulders (2.5 metres wide) in each direction, and one shared pedestrian / cycle path (2.0 metres wide) on the southern side of the bridge.

• Barriers 1.3 metres high adjacent to each shoulder on the bridge deck. One medium-performance steel traffic barrier would run adjacent to the footpath on the southern edge of the bridge deck.

• A 325 metre-long bridge deck suspended on 10 piers spaced 32.5 metres apart. The piers on the eastern and western end of the bridge would be situated on land, while the central 8 piers would be positioned in the water, oriented to the river’s flow.

• The bridge deck to the east would generally hold a 3% grade to the south, while to the west the bridge would drain along a 7% grade to the north.

• A 72 metre retaining wall would run alongside the northern edge of the bridge where it ties back into the highway alignment.

3.10.3 REMNANT BRIDGE STRUCTURE

The proposed upgrade would see the removal of the existing Nelligen bridge. The bridge deck would be removed span-by-span commencing from one abutment and working towards the opposite. The existing piers would be removed in succession. The existing abutments would be demolished, reshaped, and revegetated.

3.10.4 RETAINING WALLS

In addition to the new structure, the proposal requires the addition of a 72 metre-long retaining wall on the northern side of the alignment where it ties into the proposed highway alignment at the western bank of the river. Where required, retaining walls would generally not be visible to highway users or local residents. The walling system employed would be designed to minimise the construction footprint and allow plant growth.

3.10.5 EARTHWORKS

The proposal would require earthworks along some sections. Earthworks would generally involve removing and stockpiling topsoil, and temporarily stockpiling suitable cut material for use as fill in other locations. This would involve moving excavated materials along the alignment to fill embankment areas and batters.

Earthworks would likely require the use of trucks, bulldozers, excavators, scrapers, graders, water carts, compactors, rollers and crushing and screening plant. Earthworks may also include blasting.

Earthworks volumes have been estimated based on the concept design. There would be an overall cut volume of 21,000 cubic metres and overall fill volume of 44,000 cubic metres to complete the work; that is, a shortfall of 23,00 cubic metres of fill likely to be imported from other projects along the Kings Highway. Material may need to be imported to address this shortfall and any material not suitable for reuse on site. The suitability of excavated material for reuse on site would be determined following further geotechnical investigations during detailed design.

Minor cut batters are proposed on the eastern and western side of the Kings Highway at chainage 9400. Similar cut batters are required where the proposed bridge meets the riverbank at Maisies Lane and the entrance to Nelligen village. Highway realignment on the eastern side of the river between chainage 8550 and 8430 would require significant cutting into the existing rock. Fill batters would be required on the eastern and western approach to the proposed bridge. Cut and fill volumes and locations would be refined through detailed design.

4 URBAN DESIGN STRATEGY

4.1 Strategy Overview 20

4.2 Urban Design Objectives & Principles 20

4.3 Urban Design Elements 22

4.4 Urban Design and Landscape Strategy Plan 29

19

4.2 URBAN DESIGN OBJECTIVES & PRINCIPLES4.1 STRATEGY OVERVIEW

4.1.1 OVERVIEW

The urban design strategy strives to situate the proposed bridge structure within the existing urban fabric of Nelligen village, as well as the broader ecological context of the Clyde River valley. An holistic set of urban design principles and guidelines have been developed through a process of site visits, mapping exercises, and secondary research read in conjunction with Roads and Maritime road design standards.

4.2.1 URBAN DESIGN AIM

The over-arching aim of the urban design strategy is to ensure that the proposal is physically and visually integrated with its surrounding environment and, where possible, maximises engagement of the road user in a local context to provide a more enjoyable and interesting driving experience. The proposal would be designed in such a way as to provide a visual narrative consistent with the current Kings Highway in the Clyde River valley region.

4.2.2 URBAN DESIGN OBJECTIVES

In order to meet this aim, a set of key urban design objectives and related design principles has been developed for the proposal. These objectives and principles reference the RMS’s Beyond the Pavement guidelines and are based on an understanding of the key existing landscape and urban values of the proposal study area as well as the landscape and urban design issues that would be affected by the proposal.

The urban design objectives for the proposal at Nelligen Bridge are:• To improve the safety and operational efficiency of the highway.• To retain the existing character of the natural and cultural landscapes through

which the highway passes.• To maintain the integrity of existing ecological systems.• To minimise the construction and operational impacts of the highway on the

local community and existing environment;• To maintain and improve the amenity and economic viability of the local area;• To retain and enhance the essential qualities of the existing highway travel

experience;• To ensure that the proposal makes a positive contemporary contribution to

the local and regional landscape.

4.2.3 URBAN DESIGN PRINCIPLES

A series of urban design principles have been developed to ensure that the preceding objectives are achieved. The purpose of these principles is to integrate good urban design practice into all aspects of the concept design development and to be carried forward throughout the process to inform the subsequent detailed design and construction phases of the proposal.

The urban design principles relating to each urban design objective are outlined on the following page in Table 4.1. The table describes the interrelationship between the urban design objectives, the associated urban design principles and the areas of the highway design that would influence the development of the proposal. In some instances, a design principle may apply to more than one objective.

4.2.4 AREAS OF DESIGN INFLUENCE

The urban design principles for the proposal relate to three broad areas of design influence that include: • Road alignment design/general arrangement.

The design of the location and geometry of the proposal and related local access roads.

• Road elements design. Input into the design of bridges and safety barriers that are necessary to achieve the road alignment or are required for the effective operation of the proposal.

• Revegetation and planting design. The design of new planting or bushland reconstruction areas in order to integrate the proposal with the existing local landscape character and natural patterns, and to provide interest to the motoring experience.


Table 4.1: URBAN DESIGN OBJECTIVES AND PRINCIPLES

URBAN DESIGN OBJECTIVES & RELATED PRINCIPLES

Areas of design influence

Roa

d al

ignm

ent

desi

gn

Roa

d el

emen

ts d

esig

n

Softw

orks

des

ign

A To retain the existing character of the natural and cultural landscapes through which the highway passes.

A1 Minimise the physical footprint of the proposal, including during the construction stages. • • •

A2 Design the proposal to be physically and visually integrated with the surrounding landscape. • • •

A3 Minimise the physical and visual intrusion of road-related elements (such as safety barriers and fencing) on the local landscape. • • •

A4 Preserve the integrity of cultural heritage sites and areas of cultural importance, regardless of whether or not they contain heritage items.

• •A5 Minimise the impact of the proposal on native vegetation and

existing cultural plantings. •B To maintain the integrity of existing ecological systems.

B1 Minimise the physical footprint of the proposal, including during the construction stages. •

B2 Minimise the impact of the proposal on native vegetation. •B3 Avoid the introduction of environmental weeds. •B4 Implement comprehensive water quality control measures. • •B5 Provide connectivity and safe, effective crossings for native fauna. • •B6 Maintain the integrity of endemic plant communities and topsoils. •B7 Maintain the ecological functionality and long-term sustainability of

revegetated areas. •C To minimise the construction and operational impacts of the highway on the local

community.

C1 Minimise the physical footprint of the proposal, including during the construction stages. •

C2 Design the proposal to be physically and visually integrated with the surrounding landscape. • • •

URBAN DESIGN OBJECTIVES & RELATED PRINCIPLES

Areas of design influence

Roa

d al

ignm

ent

desi

gn

Roa

d el

emen

ts d

esig

n

Softw

orks

des

ign

D To retain and enhance the essential qualities of the existing highway travel experience.

D1 Make the character of the local topography a tangible experience for the motorist by providing, as much as possible, a constantly varying horizontal (curving) and vertical (undulating) road alignment.

•D2 Minimise the visual scale of the proposal from the motorist’s

perspective. • • •D3 Maximise the motorist’s experience of, and visual connection to,

the surrounding natural and cultural landscapes. • • •D4 Retain, and where possible improve, regional views and views to

important landmarks. • • •E To ensure that the proposal makes a positive contemporary contribution to the

local and regional landscape.

E1 Avoid the use of token “gateway” statements. Instead, utilise unique features of the local area and functional elements of the highway as visual markers and experiences that provide a sense of arrival or sense of place along the highway journey.

• • •

E2 Recognise that large-scale road elements (such as walls, cuttings, bridges and tunnels) have iconic potential and provide important visual and landscape markers. Design these elements accordingly.

•E3 Design the visual expression of the road elements to be true

to their infrastructural function, using robust materials and streamlined, uncomplicated forms.

•

21

4.3 URBAN DESIGN ELEMENTS

4.3.1 OVERVIEW

Urban design elements include bridges, walls and cuttings, that are necessary to achieve the road alignment, or safety barriers and other roadside components, that are necessary for the effective operation of the highway.

The general approach to the design of road elements would be undertaken in such a way as to satisfy the functional requirements for the safe and efficient operation of the highway while also being appropriate to their location. In all cases, the design and implementation of the road elements would need to satisfy the requirements of Austroads and RMS design guidelines and practice notes.

It is also important that, in their detailed resolution, the visual expression of the road elements is true to their function as items of contemporary highway infrastructure. Respect for the character of the local area would not be achieved by the appropriation of stylistic cues or fashions, rather through sensitive consideration of the location, placement and scale of the new elements.

Principles specific to Road Design elements

To aid the implementation of the principles in the road elements design, a series of urban design recommendations has been developed for each of the road elements that would be required for the proposal. The development of these recommendations has been guided by the following specific design criteria: • Simplicity in the design expression of the elements relating to the highway,

in order to allow the existing natural and cultural landscapes to provide the primary interest to the motoring experience.

• Practicality for ease of construction and reduced long-term maintenance.• Site specific design that acknowledges and responds to the character of the

local area, while not necessarily replicating existing features.• Consistency with the overall Kings Highway, by using elements that are

identifiably part of the highway experience in this region.• Integrity to the materials and method of construction in the final finish and

appearance of the road elements.• Sustainability in the choice of materials and resources.

Categories

Three categories of urban design elements have been identified for the proposal. These are as follows: • Landscape structures & formations - such as cuttings, embankments and

retaining walls.• Major structures - the proposed bridge crossing the Clyde River.• Roadside furniture - such as safety barriers.

Refer to individual sections of this report for recommendations regarding urban design elements.

4.3.2 LANDSCAPE STRUCTURES & FORMATIONS

Landscape structures and formations are required to reconcile the new highway levels with the levels of the existing ground (refer Figure 4.1). The types of landscape structures and formations required for this proposal are: • Cuttings where the proposal would be situated below the existing ground,

requiring excavation• Fill embankments and retaining walls where the proposal would be situated

above the existing ground, requiring the road to be elevated.

Figure 4.1 describes the principles used to determine the types of landscape elements used on this proposal.

Plate 4.1: Exposed rock cutting above Ferry Master’s Residence

Plate 4.2: Exposed rock cutting at Maisies LaneSource: SMM

Source: SMM


Highway above existing ground, requiring the road to be elevated.

Areas with sensitive existing site conditions (vegetation, drainage lines, heritage items etc) that require preservation.

Areas where the existing terrain is very steep.

Areas where the underlying geology would be self-supporting (possibly with some stabilisation) after excavation.

Areas where the underlying geology would not be able to support itself after excavation.

Areas with less sensitive site conditions, where change can be accommodated.

Retaining wall *

Retaining wall *

Bridge *

Layback cutting to flatter grade (1.5H:1V) and

revegetate

Layback cutting to flatter grade (0.5 /

1.5H:1V) and locally stabilise

Fill embankment 2H:1V and revegetate

Natural rock cutting at steepest possible grade (0.25H:1V)

Highway below existing ground, requiring excavation.

* Note: the decision to provide retaining walls or bridges would be based on a number of factors, including cost and constructability. Generally, bridges and walls would not be employed on this proposal to address landform-only issues.

* Note: A grade of 2H:1V with batter slope protection would be used as it is the steepest allowable in order to minimise the construction footprint. Revegetation techniques can be successfully employed at this grade.

* Note: steepest possible grade may result in flatter grades than desired due to geotechnical concerns. Steeper grades not suitable for all rock types.

* Note: The batter slopes are 0.5:1 for the lower benches and 1.5:1 for the final upper bench based on geotechnical advice

* Note: rock batters laid back to 1.5H:1V would be revegetated where possible, predominantly the upper slopes, to minimise long-term erosion of exposed softer rock.

* Note: Retaining walls would generally only be used where the road corridor boundary is not sufficient to accommodate batter design. Walls do not form part of the current design proposal.

Figure 4.1: Urban design elements organisational chart

Plate 4.3: Shoreline downriver from existing Nelligen Bridge, eastern side

Plate 4.4: Shoreline downriver from existing Nelligen Bridge at Nelligen, western sideSource: SMM

Source: SMM

23

4.3.3 CUTTINGS

Table 4.2 provides the following recommendations are for all cuttings along the proposal.Table 4.2: RECOMMENDATIONS FOR CUTTINGS

CUTTING ATTRIBUTE RECOMMENDATION RATIONALE

Cutting finish ¬ Where roadside cuttings are required, the natural rock surface would be maintained wherever possible. Fissures and springs are to be in-filled with shotcrete.

¬ Where the cutting face needs to be stabilised, rock anchors are preferred over shotcrete as they allow the natural rock to remain visible.

¬ The use of shotcrete is to be avoided unless absolutely necessary. Where shotcrete is required, its application is to be designed to minimise its visibility. Techniques include matching the colour and texture of the concrete to the surrounding rock, and recessing the shotcrete from the cutting face. Refer the RMS’s Shotcrete Design Guidelines.

¬ Maintaining the natural rock cutting face allows the geological character of the local landscape to be expressed in the highway corridor, providing a strong sense of place. (refer Figure 4.2 & 4.3).

¬ Exposure of rock face provides a consistency of rock colour across the region.(refer Figure 4.2 & 4.5).

Cutting profile ¬ Cutting angles would be as steep as possible, while taking into account the geotechnical constraints of each particular cutting location (refer Figures 4.2 & 4.3).

¬ Tails of cuttings are to be shaped back into the existing landform and progressively laid back in order to integrate with the existing contours (refer Figure 4.4).

¬ Steep cutting angles would reduce the overall footprint of the cutting, which in turn would minimise impacts on the surrounding landscape.

¬ Batter rounding, both over and back allows for less abrupt integration with existing landform and reduces visible impact when viewed from expected road user viewing angles.

Shoulder of cutting ¬ Would be rounded and revegetated where residual topsoils are present (refer Figure 4.5). ¬ Rounding visually softens the edges of cut batters to assist with better integration with existing landform.

¬ Rounding and revegetation of cuttings would assist with integration of the cutting with the surrounding landscape.

Toe of cutting ¬ Wherever possible, provide space at the base of cuttings for berm area adjacent the road carriageway. (refer Figures 4.2 & 4.3).

¬ A berm area at the base of a cutting can also function as a space to capture any loose material that is eroded from the cutting before it reaches the road surface.

Plate 4.5: Sloped cutting in rock

Steep rock batter overlain with vegetated soil batter above

Softer rock batters laid back and natural rock left exposed

Plate 4.6: Partially revegetated steep cutting Plate 4.7: Aggregate embedded into wall panel units selected to match the local geology

Source: Pacific Highway Glenugie Upgrade SMM Source: F3 Widening (Now the M1) SMMSource: Hume Highway Woomargama Bypass SMM


4.3.4 EMBANKMENTS

Table 4.3 provides the following recommendations are for all embankments along the proposal.Table 4.3: RECOMMENDATIONS FOR EMBANKMENTS

LOCATION RECOMMENDATION RATIONALE

Generally ¬ Reduce footprint by steepening fill batters to maximum grade of 2H:1V.

¬ Revegetate with applied topsoil and either mulched planting or hydroseeding.

¬ In open areas, limit tree planting to clusters to ensure vistas are maintained through to the broader landscape.

¬ Views from the road improve the driving experience, sense of place and orientation.

¬ Views of the road can be improved where the embankments are integrated with the existing landscape through shaping and revegetation.

In bushland areas ¬ Minimise the loss of bushland by steepening fill batters to maximum grade of 2H:1V.

¬ Application of Bushland Reconstruction technique utilising seed material embedded in existing topsoil, mulched tree material including seed, shredded trunk and branch material for stabilisation and soil ameliorants.

¬ Minimising the physical footprint of the highway reduces the need for clearing of native vegetation in bushland areas.

¬ Revegetation of embankments allows for better integration of the embankments with the character of the surrounding landscape.

Outside of bushland areas

The response would depend on the specific landscape characteristics of each embankment location of the proposal. Nonetheless, in all cases embankments would be vegetated using planting that corresponds to the adjoining landscape.

Two general responses are recommended:

¬ Where the existing landform is relatively flat and space permits, provide a flatter embankment profile (eg. 4H:1V) to better fit with the surrounding landform.

¬ Minimising the physical footprint of the highway reduces impacts on adjacent landscape.

¬ Where views of highway seen as substantial, flattening of batters would assist with visual mitigation.

In agricultural areas ¬ Minimise the loss of arable and scenic land by steepening fill batters to maximum grade of 2H:1V.

¬ It may prove beneficial to flatten out batters in some areas in order to integrate with localised land forms. This requires a detailed analysis in future stages.

¬ Cultural views associated with rural settlements provide a ‘sense of place.’

¬ Revegetation (grassing) of embankments would allow for better integration of the embankments with the character of the surrounding landscape, particularly where outside of the road corridor.

4.3.5 RETAINING WALLS

Table 4.4 provides the following recommendations are for all retaining walls along the proposal.Table 4.4: RECOMMENDATIONS FOR RETAINING WALLS

LOCATION RECOMMENDATION RATIONALE

Generally ¬ Retaining walls, in a similar fashion to the substructural components of the bridge, should be recessive in comparison to the visible superstructure components. eg. concrete parapets and barriers when viewed from a distance

¬ Concrete panel units should be placed in front of shotcrete and piles in order to provide a consistent finish. The face of the wall should be set back from the face of the parapet to increase the effect of shadow across the wall

¬ Additional texturing of the wall face could be provided a follows:

• basalt rock formed into the panel unit• vertical/horizontal corrugations added to formwork to texturise and provide shadowing to the face of the unit

¬ In accordance to Beyond Pavement guidelines

¬ In accordance to Beyond Pavement guidelines

¬ Dark aggregate in the panel units would allow the wall to recede into the landscape and would ensure this feature is in keeping with the colours of the surrounding on site rock

25

Table 4.5: RECOMMENDATIONS FOR THE BRIDGE

NU

MBE

R

CH

AIN

AG

E

DESCRIPTION

LEN

GT

H (

M)

APP

ROX

NU

MBE

R O

F

SPA

NS

HEI

GH

T (

M)

APP

ROX

STRUCTURAL DESIGN COMPONENTSFURTHER URBAN DESIGN RECOMMENDATIONS TO BE CONSIDERED FURTHER DURING DETAILED DESIGN DEVELOPMENTGIRDER

TYPEPIER TYPE

ABUTMENTS & CURTILAGE

HIGHWAY BRIDGE OVER VALLEY AND CREEK

BR01 8840 - 9140 Bridge over Clyde River

350 10 6.5- 9.2

“T” Girder

Trouser Leg Pier

Concrete panelled retaining wall (western abutment)

Spill-through abutment with rock scour (eastern abutment)

¬ The Trouser Leg pier is more visually permeable than the existing concrete peirs, and would enable views through the bridge structure (see Figure 7.6 for visualisation).

4.3.6 MAJOR STRUCTURES

Bridges

The concept design for the proposal includes one highway bridge over the Clyde River at Nelligen. Table 4.5 summarises the urban design outcomes for the bridge. The bridge drawings (refer Figure 4.2 - 4.5) summarise the approach taken to bridge design.

The proposed bridge alignment on the eastern side of the river will shift to the north by about 55 metres in order to facilitate a wider turning radius to comply with existing standards. This realignment would require the construction of a new abutment and elevated fill batter to tie the proposed vertical alignment into the existing highway configuration. The 325 metres bridge would tie into the Kings Highway on the western side of the Clyde River approximately 29 metres north and 95 metres west of the existing abutment. A 72 metre retaining wall would be required along the norther alignment of the bridge as well as some modification to the existing geometry of Maisies lane at the entrance to Nelligen village.

Plate 4.8: Existing bridge from western shore of the Clyde River

Source: Nelligen Bridge (SMM) Source: Nelligen Bridge (SMM)

Plate 4.9: Existing bridge from eastern shore of the Clyde River


27

Figure 4.2: Proposed Nelligen Bridge alignment

Figure 4.4: Section B-B - typical cross-section at centre of proposed bridge Figure 4.5: Section C-C - typical cross-section at eastern end of proposed bridgeFigure 4.3: Section A-A - typical cross-section at western end of proposed bridge

4.3.7 ROADSIDE FURNITURE

Roadside furniture elements are ancillary items necessary for the effective operation of the highway. These include roadside safety barriers and kerbs (refer Plate 4.6). Urban design recommendations are provided for these roadside elements as they can contribute positively to the character of both the highway and the local landscape.

Safety Barriers

Safety barriers along the road side generally would consist of ‘W’ beam guard rails, as verge width is limited. Other barriers include half ‘Type F’ with twin rail barriers across the bridge which may also continue across the retaining walls either side of the bridge abutments.

Table 4.6: RECOMMENDATIONS FOR ROADSIDE FURNITURE ELEMENTS

ROAD ELEMENT LOCATION RECOMMENDATION RATIONALE

SAFETY BARRIERS Across bridge ¬ Half ‘Type F’ concrete barriers with double rail which would continue across the retaining walls at end of the bridge.

¬ Consistency with other sections of the Kings Highway in this region.

Adjacent to bridge abutments above the retaining walls

¬ Half ‘Type F’ concrete barriers with double rail ¬ Consistency with other sections of the Kings Highway re-alignment.

¬ Facilitate views from the highway to the surrounding landscape, to provide a sense of connection to the local area.

At the top of fill embankments and other roadside situations

¬ ‘W beam’ guard rail would be employed due to spatial constraints and safety requirements.

¬ Where possible maximise views from the highway to the surrounding landscape.

¬ Allow for visual connections from the highway to the local landscape, to avoid the creation of an anonymous motoring experience.


4.4 URBAN DESIGN AND LANDSCAPE STRATEGY PLAN

Figure 4.6: Strategy key plan Source: SMM.

4.4.1 URBAN DESIGN AND LANDSCAPE STRATEGY PLAN

The following drawings represent the urban design and landscape strategy plan for the proposal. This strategy primarily involves the identification of significant environmental and visual impacts, as well as proposed strategies for the revegetation of any disturbed areas. The key plan (refer Figure 4.6) shows the three main sections that are illustrated in more detail on the following pages (refer Figures 4.6 - 4.9).

29

Source: SMM.


Source: SMM.

Figure 4.7: Urban design and landscape strategy plan (2 of 2)

31


5 LANDSCAPE DESIGN STRATEGY

5.1 Landscape Design Approach 34

5.2 Urban Design & Landscape Concept Plan 35

33

5.1 LANDSCAPE DESIGN APPROACH

Table 5.1: REVEGETATION URBAN DESIGN PRINCIPLES

URBAN DESIGN PRINCIPLES

B2, D2

Design the highway to be physically and visually integrated with the surrounding landscape

B3 Minimise the physical and visual intrusion of road-related elements (such as noise walls and water quality control measures) on the local landscape

C3 Avoid the introduction of environmental weeds

C6 Maintain the integrity of endemic plant communities and topsoils

C7 Maintain the ecological functionality and long-term sustainability of revegetated areas

F2 Minimise the visual scale of the highway from the motorist’s perspective

F3 Maximise the motorist’s experience of, and visual connection to, the surrounding natural and cultural landscapes

F4 Retain, and where possible improve, regional views and views to important landmarks

G1 Avoid the use of token “gateway” statements. Instead, utilise unique features of the local area and functional elements of the highway as visual markers and experiences that provide a sense of arrival or sense of place along the highway journey.

5.1.1 OVERVIEW

Highway planting and revegetation aims to integrate the proposal with the surrounding landscape, thereby assisting to minimise the potential visual and ecological impact of the new works. Refer Table 5.1 for a summary of the urban design principles that relate to planting design.

The general approach to the planting design is to provide a well vegetated road corridor that aims to integrate the highway with the surrounding landscape and provide motorists with a sense of place along the highway journey. In order to achieve this, the planting must strike a balance between screening the highway and works areas from the sensitive views from surrounding areas and maintaining key views from the highway to the surrounding landscape.

The planting and revegetation design also aims to minimise the potential ecological impacts of the proposal by stabilising earthworks to prevent erosion, and reinforce existing habitats and ecological corridors through species selection. Several different techniques have been developed to achieve these goals. Techniques employed would be based on landscape context and the best and most-efficient means to achieve these goals.

5.1.2 LANDSCAPE STRATEGY

The planting concept has been guided by the following design principles: • revegetation of residual land affected by highway construction work• the type of revegetation would be determined by a combination of

surrounding landscape character eg. rural as well proximity to existing ecological habitats and wildlife corridors

• use of bush reconstruction and regeneration as a revegetation technique for off-line sections of highway that pass through dense bushland

• revegetation of outside verges wherever possible to minimise the visual scale of the highway, and of roadside cuttings and retaining walls

• revegetation of fill embankments and shallow cut batters to stabilise the earthworks, minimise their visual impact and integrate them with the character of the surrounding landscape

• provision of planting and revegetation to screen the temporary ancillary works areas from sensitive adjacent land uses

• use of provenance plant material (plants grown from locally collected seeds) wherever possible.

5.1.3 IMPLEMENTATION METHODS

The proposal would be revegetated utilising a combination of techniques, as follows (refer Figure 5.2): • Hydroseeding - pasture grass • Compost blanket • Direct seeding.

5.1.4 REVEGETATION SUMMARY

Table 5.2 summarises the revegetation methods for the proposal.Table 5.2: REVEGETATION METHODS

TECHNIQUE LOCATION OF USE

Hydroseeding ¬ Restoration of temporary ancillary works areas

Compost blanket ¬ Embankments associated with the new highway alignment and maintenance/ construction access track

Direct seeding ¬ Old highway alignment

DOCUMENTATION

¬ Standard RMS specifications (R176 Seed procurement, R178 Vegetation)

¬ Preparation of species lists. Refer species lists for indicative species

OPPORTUNITIES

¬ Cost effective broad-scale solution utilising endemic seed material sourced from the local region

¬ Provides better long-term outcome than planting as seedlings develop faster.

CONSTRAINTS

¬ Limited control over where specific species germinate

¬ Timing of seed application may suit proposal but not individual species.


5.2 URBAN DESIGN & LANDSCAPE CONCEPT PLAN

Figure 5.1: Concept key plan Source: SMM.

5.2.1 URBAN DESIGN AND LANDSCAPE CONCEPT PLAN

The following drawings represent the urban design and landscape concept plans for the proposal. The key plan below (refer Figure 5.1) shows the three main sections that are illustrated in more detail on the following pages (refer Figures 5.2 - 5.4).

35

Figure 5.2: Concept key plan

Source: SMM.36 KINGS HIGHWAY UPGRADE | NELLIGEN BRIDGE | URBAN DESIGN REPORT AND LANDSCAPE CHARACTER AND VISUAL IMPACT ASSESSMENT


37

Source: SMM.



Figure 5.6: Typical cross section through modified exposed rock cutting above Ferry Master’s Residence

Figure 5.5: Typical cross section of new embankment approaching eastern abutment of the proposed bridge.

5.2.2 TYPICAL ROAD CROSS-SECTIONS

The following road typical cross-sections illustrate the potential extent and scale of the proposal and as well as physical impacts on the existing landscape. The landscape revegetation methodologies described in the previous plans would be implemented across these different scenarios. Figures 5.5 - 5.6 show typical cuttings and embankments that would be required to facilitate the new highway alignment on the eastern bank of the Clyde River approaching the proposed bridge. These sections indicate the extent of cut and fill, the proposed slopes of the cuttings and batters, as well as areas of revegetation. Table 5.3 describes the proposed landscape revegetation areas, general vegetation communities, and specific planting species.

39

5.2.3 REVEGETATION SPECIES

A planting and revegetation palette would be developed for the proposal, based on the species endemic to the proposal study area and site.

The species mixes would be categorised based on existing vegetation formations and communities and located closely to these original communities and where appropriate, in order to revegetate the areas affected by construction. Typically, a diverse understory within an open tree canopy be the desired outcome for much of the proposal. Riparian and wetland species typical of lowland forest ecosystems would be appropriate for areas of the proposal adjacent to the Clyde River.

The areas and communities are noted in Table 5.3, discussed in Section 2.10 and mapped in Figure 2.10.

Table 5.3: REVEGETATION COMMUNITIES

VEGETATION COMMUNITY VEGETATION STRUCTURE SPECIES

Batemans Bay Cycad Forest Eucalypt forest with open shrub layer and grassy groundcover found on sheltered slopes on coastal lowlands below 250 metres.

Trees: Eucalyptus globoidea, Corymbia maculata, Allocasuarina littoralis, Eucalyptus paniculata.

Shrubs: Macrozamia communis, Persoonia linearis, Platysace lanceolata, Hibbertia aspera, Podolobium ilicifolium, Leucopogon lanceolatus.

Groundcover: Entolasia stricta, Dianella caerulea, Lepidosperma laterale, Lomandra multiflora.

South Coast River Flat Forest Open eucalypt forest with an open shrub layer and dense cover of grasses & forbs. Found on sandy alluvial flats along major streams up to 300 metres along the Clyde River.

Trees: Eucalyptus elata, Angophora floribunda.

Shrubs: Rubus parvifolius, Breynia oblongifolia, Hymenanthera dentata, Acacia mearnsii.

Groundcover: Microlaena stipoides, Dichondra spp., Lomandra longifolia, Carex longebrachiata, Pteridium esculentum, Adiantum aethiopicum, Oplismenus aemulus, Pratia purpurascens, Echinopogon ovatus, Entolasia marginata, Stellaria flaccida, Desmodium varians.

Murramarang Lowlands Forest Eucalypt forest with open shrub layer and prominent grassy groundcover. Loamy soils on coastal lowlands below 60 metres.

Trees: Eucalyptus paniculata, Allocasuarina littoralis, E. longifolia, Corymbia maculata.

Shrubs: Hibbertia aspera, Leucopogon juniperinus, Notelaea longifolia.

Groundcover: Lomandra longifolia, Imperata cylindrica, Pratia purpurascens, Entolasia stricta, Dianella caerulea, Lepidosperma laterale, Dichondra spp., Lagenifera stipitata, Oplismenus imbecillis, Brunoniella pumilio, Schelhammera undulata.

Southeast Lowland Grassy Woodland

Eucalypt woodland with sparse strata of small trees and shrubs and a grassy groundcover with diverse forbs and graminoids.

Trees: Acacia mearnsii, Angophora floribunda, Eucalyptus globoidea, Eucalyptus tereticornis.

Shrubs: Bursaria spinosa, Ozothamnus diosmifolius.

Groundcover: Cheilanthes sieberi, Desmodium varians, Dichondra spp., Echinopogon ovatus, Eragrostis leptostachya, Glycine clandestina, Glycine tabacina, Hydrocotyle laxiflora, Hypericum gramineum, Lepidosperma laterale, Lomandra longifolia, Lomandra multiflora subsp. multiflora, Microlaena stipoides, Oxalis perennans, Themeda australis.

Estuarine Mangrove Forest Low dense forest or scrub with bare ground or patchy herbaceous groundcover found on estuarine mudflats exposed to daily tidal inundation.

Trees: Avicennia marina subsp australasica, Aegiceras corniculata.

Groundcover: Sarcocornia quinqueflora.

Floodplain Swamp Forest Low, rather dense forest with open shrub layer and semi-continuous groundcover found on brackish coastal floodplain drainage lines and depressions below 10 metres.

Trees: Casuarina glauca, Melaleuca styphelioides.

Groundcover: Commelina cyanea, Phragmites australis, Alternanthera denticulata, Carex apprssa, Centella asiatica, Cynodon dactylon, Juncus kraussii.


41

6.1 Overview 44

6.2 Landscape Character Zones 45

6.3 Landscape Character Zone Impact Summary 51

6 LANDSCAPE CHARACTER ASSESSMENT


6.1.1 OVERVIEW

Roads and Maritime’s ‘Guidelines for Landscape Character and Visual Impact Assessment’ (RMS, 2009) provides the following definition of landscape character :

‘Landscape character is the aggregate of built, natural and cultural aspects that make up an area and provide its unique sense of place. Landscape in this context is taken to include all aspects of a tract of land - the built, planted and natural topographical and ecological features.’

In applying this definition to the specific conditions within the study area and the features of the proposal, the landscape character assessment also considers how the highway is used and how it functions as a part of the region. The assessment has looked at both existing landscape character and landscape character post-completion.

6.1.2 LANDSCAPE CHARACTER ASSESSMENT METHODOLOGY

The landscape character zones facilitate detailed assessment of the character of the proposal study area, of the proposal within it, and of the magnitude, sensitivity and impact likely on the landscape character of each zone to be experienced as a result of these proposal works. Refer the following section for a description of the landscape character zones.

Magnitude

In landscape character assessment, magnitude refers to the type of proposal and its compatibility with the existing landscape character. All anticipated elements of the proposal, including the bridge, alignment, road infrastructure, footpaths, planting, lighting, etc, are considered. The scale of the element (height, length), as well as its location or setting (on floodplain, near the town), all have a bearing on the magnitude of the physical presence of the works.

A high magnitude results if the proposal is a major development or piece of road infrastructure and contrasts highly with the surrounding landscape, or entails heavy modification of the existing landscape, for example, the large scale removal of existing vegetation. A moderate magnitude rating would result if the proposal is moderately integrated into the landscape. A low magnitude rating would occur if the proposal is of a small scale and integrates well into the landscape.

6.1 OVERVIEW

Table 6.1: ROADS AND MARITIME IMPACT GRADING MATRIX The magnitude impact rating also considers whether the proposal has a positive or negative impact on the landscape character of the zone. For example, a proposal may be of a large scale but may provide beneficial outcomes such as increased open space, enhancement of the areas ‘sense of place’, and better connectivity.

Sensitivity

Sensitivity is assessed on the perceived value of the existing landscape character. A judgement has been made as to the quality of the landscape, its cultural and historical importance to the community, scenic quality, and overall composition of the place and its inhabitants. The following sensitivity judgements have been used as the basis for this assessment:• Places with high social, recreational, and historical significance to local residents

have higher sensitivity• Generally, water and natural environments are more highly valued than

modified areas• Areas of unique scenic quality have higher sensitivity• A pristine environment would have greater sensitivity with less ability to

absorb new elements in the landscape than modified landscapes or those areas with contrast and variety of landscape types

• The number and frequency of viewers effects sensitivity, with retail, residential and open space.

Impact

Impact is the combination of the magnitude and sensitivity rating in accordance with the Impact Assessment Grading Matrix (refer Table 6.1).

Magnitude

High Moderate Low

Negligible

Sens

itivi

ty

Hig

h

High impact High to Moderate

Moderate impact

Negligible

Mode

rate

High to Moderate

Moderate impact

Moderate to Low

Negligible

Low

Moderate impact

Moderate to Low

Low impact Negligible

Neg

ligib

le

Negligible Negligible Negligible Negligible

43

6.2 LANDSCAPE CHARACTER ZONES

From the southeast, the existing highway passes through the Batemans Bay Cycad Forest vegetation community before descending into the floodplain swamp forests and mangroves of the Clyde River Valley. Given the heavy recreational boat traffic on the Clyde, the proposed bridge and highway realignment would be experienced equally from both the land and the water. On the western riverbank, the highway passes Nelligen Village to the south and coastal wetlands to the north. The rolling hills and valleys that surround the site are generally characterized as South Coast Lowland Forests, through which the Kings Highway passes as it continues to the northwest.

Following field and desktop studies, the proposal study area has been divided into five landscape character zones (LCZs). The zones correspond to landscape character types in the area and allow for a more detailed discussion of the character of each precinct, of the proposal within it, and of the potential impact on the landscape character. Each zone has been defined through gaining an understanding of land use, topography, and vegetation in combination with other factors (refer Figure 6.1).

The four landscape character zones are: • LCZ1 - Nelligen Village• LCZ2 - Estuarine Wetlands• LCZ3 - Clyde River Valley• LCZ4 - Floodplain Swamp Forest• LCZ5 - Batemans Bay Cycad Forest

Figure 6.1: Landscape character zones

Artwork: SMM


6.2.1 LANDSCAPE CHARACTER ZONE 1 ASSESSMENT

Existing Landscape Character

The main portion of Landscape Character Zone 1: Nelligen Village is situated on the banks of the Clyde River and extends about 600 metres westward from the waterfront through the town. The Kings Highway runs along the northern edge of the town from the point at which the existing bridge meets the western riverbank. This area is typified by single occupancy residential development and low density commercial activity. A similar character of residential development is mirrored on the eastern side of the river adjacent to Bridge View Road, however it bears little impact on the driver’s experience owing to its low-lying, well-screened position relative to the highway.

In this character zone, the Kings Highway is comprised of a two lane road with a eastbound and westbound lane that is flanked by a steep embankment cut to the south and the Clyde River’s estuarine wetlands to the north. Views into Nelligen Village are obscured by alternating embankments and dense vegetation; the town can be clearly seen when approaching from the east on the existing bridge. Views to the north are partially screened by existing vegetation with periodic breaks that give way to clear sightlines over the wetland (refer Figure 6.2 and Plate 6.1).

Plate 6.1: Landscape character zone 1 character imagesFigure 6.2: Landscape character zone 1 extent


Proposal works in this LCZ would include demolition and removal of the existing bridge and abutments, construction of a 325 metres long span bridge, a 72 metre retaining wall, new embankments and cut betters, realignment of Maisies Lane at the entrance to Nelligen village (including a pedestrian footpath), and tie-ins with the existing Kings Highway at Reid Street. An access road as well as crane pads and piling platforms would be built adjacent the bridge piers during construction.

The landscape character of much of the proposal would retain a similar experiential quality. Views into Nelligen village would be preserved on approach from the proposed bridge. New feature plantings would screen existing structures from highway traffic, and serve as a visual indicator of the village’s entrance at Maisies Lane. Table 6.2 provides a summary of the landscape character assessment.

Sensitivity

The landscape character of this zone has an attractive and dynamic appearance due to the spatial qualities produced by a repeating sequence of cut, embankment, and forest. The gradual slope towards the river and slight bend in the highway results in a contrasting effect of enclosure and reveal that is reinforced by the alternating patches of shade and sunlight. Plate 6.1 depicts the view west from the existing bridge towards Nelligen village, as well as an elevated view of the approach to Maisies Lane from the vantage point of a cut batter adjacent to the highway. This character results in a High sensitivity to the proposal.

Magnitude

The proposal would substantially alter the existing highway alignment across the Clyde River and along the northern edge of the character zone. The visual elements of visible works in this zone would comprise new batters and embankments, existing road pavement widening, reconfiguration of Maisies Lane, as well as the demolition of the existing bridge and construction of the new structure including bridge parapets and safety rails, piers, and abutments. All of these features are of a similar road language to the existing highway so that the overall, the magnitude of the proposal would be Moderate due to the relatively contained works and similar suite of road infrastructure.

Landscape Character Impact

The qualitative assessment indicates that the landscape character impact of the proposal in this zone is likely to be Moderate / High due to the High sensitivity of the zone and the Moderate magnitude of the works.

Partially screened views of the Clyde River

View of Nelligen Village from existing bridge

LCZ1

Source: Department of Lands, RMS and SMM. Source: SMM.

Source: SMM.

Table 6.2: LANDSCAPE CHARACTER ZONE 1 IMPACT ASSESSMENT

Landscape Character Zone 1: Nelligen Village

Sensitivity High

Magnitude Moderate

Landscape Character Impact Moderate / High

45

Figure 6.3: Landscape character zone 2 extent

LCZ2

Plate 6.2: Landscape character zone 2 character images



The banks of the Clyde River valley at Nelligen are home to biologically diverse ecotone of estuarine vegetation communities. Tidal fluctuations along the riverbank provide ideal hydrological conditions for seagrass meadows, saltmarshes, and mangroves. As the banks rise, these estuarine communities gradually give way to floodplain swamps and lowlands forests typical of the region. This character zone is listed under the SEPP14.

The Kings Highway runs along the southern edge of this character zone, and divides the estuarine wetlands from Nelligen village. While the southern side of the road is characterized by steep cuts and dense vegetation, the wetlands provide contrasting views to the north interspersed with partial screening by stands of trees. The area of land immediately adjacent to the western abutment of the existing bridge also provides thinly-screened and picturesque views north over the Clyde River. When approaching from the west, periodic breaks in the vegetation framed views over the wetlands towards the Big4 Nelligen Holiday Park. (refer Figure 6.3 and Plate 6.2)

Landscape Character assessment

The proposed works in this area include the realignment of the Kings Highway and addition of the new bridge, necessitating the construction of a new bridge abutment and 72 metre retaining wall. The proposed bridge would land approximately 29 metres north and 95 meters west of the existing western abutment.

The landscape character in this zone is likely to contribute to higher visual exposure of the proposed works given its proximity to the river, holiday park, and Nelligen village, as well as the limited screening afforded by the low estuarine vegetation. The cultural value of Nelligen’s waterfront would not be impacted, and the relocation of the existing bridge abutment would return a portion of the riverfront to adjacent landscape. Table 6.3 provides a summary of the landscape character assessment.

Sensitivity

As shown in Plate 6.2, the estuarine wetlands are highly visible from the east as one traverses the bridge, as well as from the holiday park in the north. The wetlands are similarly visible by boat. Given their conspicuous location, biological diversity and importance in the riverine hydrologic cycle, and degree of protection under SEPP14 legislation the wetlands are deemed to be highly sensitive to the proposed works.

Magnitude

The magnitude of the proposal in this area is concentrated around the highway realignment and associated bridge construction at the riverbank. While this reconfiguration would directly impact a small portion of the existing wetland vegetation communities, it would be offset by the demolition of the existing bridge and subsequent revegetation. Further west of the riverbank the proposal largely follows the existing road alignment and is unlikely to result in a significant impact.


The qualitative assessment indicates that the landscape character impact of the proposal in this zone is likely to be Moderate to High due to the High sensitivity to change of the precinct and the Moderate magnitude of the works.

View of wetlands from existing bridge

Wetlands as seen from Big4 Nelligen Holiday Park


Landscape Character Zone 2: Estuarine Wetlands

Sensitivity High

Magnitude Moderate

Landscape Character Impact Moderate / High

Source: Department of Lands, RMS and SMM. Source: SMM.

Source: SMM.



LCZ3

Source: Department of Lands, RMS and SMM.



There is substantial recreational boat traffic along the Clyde River which passes under the Kings Highway at Nelligen Bridge. This route is popular amongst locals and visitors alike and is supported by a large number of private docks, a public wharf at Nelligen, and ample boat rental opportunities at Batemans Bay and the local Big4 Holiday Park. Historically, Nelligen is the site of an important river punt which shuttled up to 30,000 vehicles across the Clyde River at its peak in 1963. The punt ceased operation following the construction of the bridge in 1964, however its presence is still felt through Nelligen’s civic orientation towards the river as well as interpretive signage located along Wharf Street.

Nelligen Bridge is the only point at which the Kings Highway crosses the Clyde River. From the perspective of the bridge, pedestrians and cyclists have clear views down river and towards the shoreline of Nelligen Village (the footpath is only on the south side of the bridge). Drivers experience a panoramic vista to the north and south which is only partially obscured by a metal crash barrier. (refer Figure 6.4 and Plate 6.3).



The Clyde River character zone would be most impacted by the construction of the proposed bridge and demolition of the existing bridge. These impacts would be most noticeable during the construction phase, but are not expected to impact the landscape character in the long term. Reconfiguration of the eastern approach to Nelligen Bridge would shift the highway to the north, and thereby alter the visibility of Nelligen Village from the driver’s perspective. Table 6.4 provides a summary of the landscape character assessment.

Sensitivity

The construction and demolition methodology of the proposed works is designed to minimise environmental or circulatory impacts to the Clyde River. It may be required to construct a temporary wharf or rock work platform near the eastern abutment should the water depth be too shallow for a pile rig or barge. Plate 6.3 depicts the view of Nelligen bridge from downstream and demonstrates the typical vegetated condition of the Clyde River.

Magnitude

The magnitude of the proposed works would be highest during the construction and demolition phase. Temporary infrastructure on the Clyde River would include sediment and erosion controls, barges, pile rigs, potential temporary wharves, in addition to steel casings and scaffolding around the new bridge piers. However, the completed bridge would have a similar character and appearance as the existing structure, albeit with an additional two piers to accommodate its length.


The qualitative assessment indicates that the landscape character impact of the proposal in this zone is likely to be Moderate due to the Moderate sensitivity of the zone and the Moderate magnitude of the works.

Northward view of the Clyde River

Nelligen Bridge as seen from the Clyde River

Source: SMM.

Source: SMM.


Landscape Character Zone 3: Clyde River Valley

Sensitivity Moderate

Magnitude Moderate

Landscape Character Impact Moderate

47


LCZ4





The Kings Highway passes through a low-lying floodplain swamp forest as it approaches the river. This vegetation community is typical of the lower reaches of the Clyde River valley and is characterised by species that can withstand periodic inundation during high water events. As a result of this dense vegetation- particularly the mangrove communities at the water’s edge views towards the river are heavily screened. Drivers experience this character zone as they complete a 90° turn to the west after passing through a deep rock cut. The experience is a sudden and expansive view over the Clyde River and Nelligen Bridge.

The land to the immediate south of the existing bridge abutment has been cleared and replaced with turf, providing unobstructed views to the west. This clearing is intended to provide clear sightlines for vehicles turning onto and off of Thule Road. In the proposed scheme, access to the Kings Highway from Thule Road would be closed and the current cleared area would be partially revegetated with endemic species (refer Figure 6.5 and Plate 6.4).

Landscape Character assessment

The proposed works in this area include the realignment of the Kings Highway to improve the curve for vehicles approaching the Clyde River. This would require the construction of a new bridge abutment approximately 55 metres north of the current abutment. The vertical road alignment of the new bridge would be similar to that of the existing bridge; the road surface would remain approximately 12 metres above the current ground level.

The dense riverside vegetation in this character zone would help to screen the proposed works from the river. Currently, the area to the south of the existing abutment at the intersection of the Kings Highway and Thule Road is cleared and turfed. As part of the realignment works, this section of Thule Road would be removed and the cleared area would be revegetated. Table 6.5 provides a summary of the landscape character assessment.

Sensitivity

Plate 6.4 demonstrates the typical vegetated condition where the floodplain forest meets the river as seen from the perspective of the current bridge. The proposed works would require the partial removal of existing vegetation, however this would be offset by the revegetation around the demolished abutment and areas around the Thule Road closure. The current views towards Nelligen village would shift towards the north, somewhat limiting the direct views into town.

Magnitude

The magnitude of the proposal in this area is concentrated around the highway realignment and associated bridge construction at the riverbank. Views from Nelligen village and adjacent residential structures would be mitigated by the dense riverine vegetation.


The qualitative assessment indicates that the landscape character impact of the proposal in this zone is likely to be Low due to the Low sensitivity to change of the precinct and the Moderate magnitude of the works.

Views to the east as seen from Nelligen Bridge

Nelligen as seen from the eastern shoreline


Landscape Character Zone 4: Floodplain Swamp Forest


Magnitude Moderate

Landscape Character Impact Moderate

Source: SMM.

Source: SMM.



LCZ5




The eastern portion of the study area lies entirely within the Batemans Bay Cycad Forest vegetation community. This character zone is defined by eucalypt woodlands with a sparse understory, particularly as the highway emerges from the Benandarah State Forest to the East.

At the intersection with Old Nelligen Road the Kings Highway lies about 36 metres above water level, allowing for intermittent views over the Clyde River through the canopy of the adjacent trees. The highway then descends towards the river through a valley of steep, partially-vegetated rock cuts that occasionally give way to expansive views over the river. The historic Ferry Master’s Residence at the top of the rock cut offers a panoramic over the Kings Highway and Clyde River towards the rolling hills of Buckenbowra State Forest to the west. (refer Figure 6.6 and Plate 6.5).



The alignment of the proposed works is relatively similar to the existing configuration between Bridge View Road and to roughly 125 metres north of Old Nelligen Road. Adjustments to the alignment and batters would improve driver safety and upgrade the roadway to current standards. The eastern extent of the study area would tie into the existing highway about 160 metres east of Bridge View Road.

Closure of the Kings Highway at Thule Road would require residents to access their properties via Bridge View Road. To accommodate the increase in traffic, the proposal includes localised road widening and an upgrade of the at the intersection of Bridge View Road and the Kings Highway. Table 6.6 provides a summary of the landscape character assessment.

Sensitivity

The proposed works largely follow the existing alignment of the Kings Highway and are not expected to pose a significant impact to the surrounding properties or vegetation. New cut and fill battens would be revegetated wherever possible to maintain a consistent appearance with the surrounding woodland. The highway corridor has historically experienced significant modification, particularly at the intersection of Old Nelligen Road.

Magnitude

The proposal would have the largest short- and long-term impact at cutting above the Ferry Master’s residence and, to a lesser extent, at the intersection of Bridge View Road. Upgrade works and road widening would increase the safety and functionality of the intersection thereby improving the driving experience, particularly for local residents. Proposed works in this area are mainly comprised of upgrades to existing conditions,and are not expected to drastically alter the current landscape character.


The qualitative assessment indicates that the landscape character impact of the proposal in this zone is likely to be Low due to the Low sensitivity of the zone and the Low magnitude of the works.

Rock cuts on approach to Nelligen Bridge

Nelligen Bridge seen from the adjacent hills

Source: SMM.


Landscape Character Zone 5: Batemans Bay Cycad Forest


49

6.3 LANDSCAPE CHARACTER ZONE IMPACT SUMMARY

6.3.1 IMPACT SUMMARY

The landscape character impact assessment of the proposal described above represents a qualitative assessment of the five Landscape Character Zones.

OVERALL STUDY AREA IMPACTS

The predicted landscape character impacts for each zone reflect the corresponding local conditions. They further reflect the scale of the proposal within each zone’s setting.

Overall, there is a gradient of increasing impact to the current landscape character as one moved from east to west. The largest potential impacts can be found in Zone 1: Nelligen Village and Zone 2: Estuarine Wetlands. These zones would experience the most substantial modification to the current road alignment, and therefore stand to receive the highest degree of alteration. The level of impact is exacerbated by the fact that these areas are the most sensitive to change, with Zone 1 as the site of Nelligen’s local population, and Zone 2 listed under state environmental protection.

Impacts to the character of the remaining three zones are largely confined to the construction period, with Zone 3: Clyde River Valley as the most susceptible during this period. The demolition of the existing bridge and construction of the new bridge would be highly visible from the river, Nelligen Village, local residents, and vehicular traffic. However, the proposed works are similar to existing conditions, and are not expected to introduce any elements that would impact the landscape’s character in the long term (and less so as new vegetation matures).

Despite some modification to existing views from the Kings Highway (particularly in the driver’s orientation while crossing the new Nelligen Bridge) it is expected that the proposed works would improve safety for road users, the impression of landscape character, and roadside scenery in general. The highway would be more responsive to the topography of river valley slopes, particularly in the approach to the proposed bridge from the east.

Table 6.7: LANDSCAPE CHARACTER ZONES IMPACT SUMMARY

LCZ SENSITIVITY MAGNITUDELANDSCAPE CHARACTER

IMPACT

LCZ 1: Nelligen Village High Moderate Moderate to High

LCZ 2: Estuarine Wetlands High Moderate Moderate to High

LCZ 3: Clyde River Valley Moderate Moderate Moderate

LCZ 4: Floodplain Swamp Forest Moderate Moderate Moderate

LCZ 5: Batemans Bay Cycad Forest Moderate Low Moderate to Low


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7 VISUAL IMPACT ASSESSMENT

7.1 Overview 54

7.2 Visual Catchment Zones 55

7.3 Viewpoint Assessment Methodology 56

7.4 Primary Visual Catchment Zone 57

7.5 Secondary Visual Catchment Zone 59

7.6 Road User Views 61

7.7 Summary of Visual Impacts 62

7.8 Landscape Visualisations 63


7.1 OVERVIEW

Table 7.1: ROADS AND MARITIME IMPACT GRADING MATRIX The potential visual impact of the proposal has been assessed in relation to a number of key viewpoints. It is based on the existing pattern of land use and development adjoining the works. The method of assessment involved: • defining the scale or size, form and type of the proposal within the context of

the study area • establishing an estimated visual catchment, through desktop analysis and

ground truthing on site • identifying key viewpoints from where the proposal would be visible • assessing the level of potential visual impact on viewers at these viewpoints

from the proposal.

7.1.1 VISUAL IMPACT ASSESSMENT METHODOLOGY

The magnitude of change to existing views and the sensitivity of the viewer has been assessed for each of the chosen viewpoints (refer Table 7.1).

Magnitude

Magnitude of change to existing views refers to the nature and scale of the proposal, and the extent and proximity of the view to the works. Magnitude represents the contrast in scale, form and type of the proposal works to the location and context to which it is to be placed. A high magnitude results if the proposal works are of a major scale and are considered out of scale or uncharacteristic of the existing visual character, or if there is considerable modification to the existing landscape. A moderate magnitude would result if the proposal works are prominent but not considered to be substantially uncharacteristic with the existing visual character. A low magnitude results if there is minimal alteration to the existing view and the works are of a scale and nature that is consistent with the existing visual character.

Sensitivity

Sensitivity is the measure of the visual importance of the view and is dependent on the following: • distance between viewer and the works• the category of viewer such as resident, visitor or worker• the elements of the proposal that are visible• importance of the view.

Visual sensitivity includes the consideration of the perceived cultural and historical values of the visual environment and the elements within it. Generally, viewers with the highest sensitivity include: • residents who have existing attractive views that would be affected by the

proposal works • users of public open space where their attention is focused on the visual

landscape, for example, lookouts or other scenic natural areas • communities that place high cultural and historical significance on the visual

landscape.

Viewers with the lowest sensitivity are most likely to be: • employees focused on their work • motorists, particularly drivers, whose attention is focused on driving.

Impact

Impact is the combination of the magnitude and sensitivity rating in accordance with the Impact Assessment Grading Matrix (refer to Table 7.1). Visualisations of the potential impacts rendered by the propsal can be seen in Section 7.8.

Magnitude

High Moderate Low

Negligible

Sens

itivi

ty

Hig

h

High impact High to Moderate

Moderate impact

Negligible

Mode

rate

High to Moderate

Moderate impact

Moderate to Low

Negligible

Low

Moderate impact

Moderate to Low

Low impact Negligible

Neg

ligib

le

Negligible Negligible Negligible Negligible

53

7.2 VISUAL CATCHMENT ZONES

The physical characteristics of the site, the topography of the existing road corridor, and the extents of proposed works define the visible area of the study. Or, in other words, the catchment from which the works are potentially visible (refer Figure 7.1). This visual catchment has been defined into two Visual Catchment Zones (VCZ) based on geographic proximity to the proposal and include: • Primary VCZ of approximately 0 - 200 metres• Secondary VCZ of approximately 200 - 400 metres.

Figure 7.1: Visual catchment zones

Artwork: SMM


7.3 VIEWPOINT ASSESSMENT METHODOLOGY

Within the Visual Catchment Zones (VCZ), potential key viewpoints have been identified. Some of these viewpoints are representative of locations that were unable to be inspected during site investigations, including existing homesteads and property access roads. However, they have been identified as potential viewpoints through desktop analysis.

Mapping & Imagery

The chosen viewpoints are assessed using the following methods:• desktop studies of aerial, cadastral and topographic mapping• field investigations and imagery.

Viewpoints assessment:

In measuring the impact of change, the following conditions are taken into account:• distance between viewer and proposed works• elevation change between viewer and proposed works• a visual and desktop assessment made of the vertical & horizontal field of view

impacted on by physical features such as landform and vegetation• an assessment made of the type of intervention made by the proposal into the

existing landscape.

Assessment conditions:

The assessments are collated in order to determine the impact of the proposal against two primary viewing conditions: • the impact upon users of the highway itself or other connecting roads • the impact from private properties or other selected locations likely to be

accessed by viewers where they fall within the visual catchment.

Artwork: SMM

Figure 7.2: Primary visual catchment zone

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7.4 PRIMARY VISUAL CATCHMENT ZONE

7.4.1 DESCRIPTION

Following an assessment of the surrounding terrain, the Primary Visual Catchment Area has been determined as any area within 200 metres from the proposed works.

The definition of the zone is relevant for motorists, pedestrians, and cyclists who would experience the proposal firsthand. When heading west along the Kings Highway, motorists would descend the into the river valley through dense, mature native vegetation and steep cut batters that encloses the road on both sides. Large exposed rock cuttings would be visible to motorists travelling along this section of the highway. On the western side of the road the escarpment falls aways steeply with only the canopies of native vegetation visible to motorists. The proposed alignment then arcs to the left, with periodic gaps in the vegetation that provide views towards Nelligen.

The new alignment continues for 55 metres north of the existing abutment before exiting the dense riparian vegetation and opening to expansive views of the Clyde River. The new Nelligen Bridge extends for 325 metres over the river, providing views in both directions through visually-permeable guard rails. The experience of crossing the bridge would be somewhat different from the existing situation, as the alignment approaches Nelligen from northwest as opposed to directly from the west.

The proposed bridge would reach land 29 metres north and 95 metres west of the existing abutment. The reconfigured intersection of Maisies Lane and the Kings Highway marks the entrance to Nelligen, which is indicated by feature planting. The new highway alignment would continue westward through low-lying estuarine wetlands, with occasional views to the north through copses of trees. Modified embankments rising from the south are proposed to be revegetated with low shrubs and native grasses, which would have the affect of reducing the visual impact. The proposed works would then tie into the existing Kings Highway at Ried Street.

7.4.2 VIEWPOINTS

Five key viewpoints have been identified within the zone due to their proximity to the proposal (refer Figure 7.2). The viewpoints are:• 1: Clyde River off Thule Road• 2: Clyde River at existing Eastern Abutment• 3: Ferry Master’s Residence (for indicative visualisation see Section 7.8)• 4: Wharf Street (for indicative visualisation see Section 7.8)• 5: Nelligen Village from Maisies Lane.

General characteristics of each of these viewpoints are provided in Table 7.2.


Table 7.2: PRIMARY VISUAL CATCHMENT ZONE IMPACT ASSESSMENT

VIE

WPO

INT

NO

.

VIEW LOCATION & ASPECT ELEMENTS OF PROPOSAL POTENTIALLY VISIBLE DIS

TAN

CE

TO

PR

OPO

SAL

(M

)

VIS

UA

L SE

NSI

TIV

ITY

MA

GN

ITU

DE

OF

VIS

UA

L EF

FEC

T

OV

ERA

LL

RAT

ING

OF

VIS

UA

L IM

PAC

T

DESCRIPTION / COMMENT

V1

¬ Looking west north-west across the Clyde River towards Nelligen Village and the existing bridge.

¬ Long-range views across the river, as well as clear views upstream and downstream. There is sparse vegetation along the shoreline that provides minimal screening.

¬ New bridge including concrete piers, western abutment, southern parapet, and guard rails.

¬ Decommissioned existing abutment (to be repurposed as lookout point as an extension of the existing park).

0-200m M M M

¬ The proposed bridge would run between 50m - 90m to the north of the existing alignment, away from the vantage point of the viewpoint.

¬ The proposed western abutment would move to the northwest of the existing structure, and would be partially screened from view by the riverbank and wetland vegetation.

V2

¬ Looking west towards Nelligen along the existing alignment of the Nelligen Bridge.

¬ Northward views are presently limited by the abutment and piers of the existing bridge. There are clear views to the south over the Clyde River.

¬ New bridge including concrete piers, western abutment, southern parapet, and guard rails.

¬ Decommissioned existing abutment (to be repurposed as lookout point as an extension of the existing park).

0-200m M M M

¬ The proposed bridge would cross the river approximately 55m north of the viewpoint, opening short range views of the river. On the western bank, the proposed bridge would land to the northwest of the current abutment and would be partially screened from view by estuarine vegetation.

¬ The partial closure of Thule Road and subsequent revegetation of the area around V2 would screen views to the west. These views would become increasingly obscured as vegetation matures over time.

V3

¬ Looking west north-west from the vantage point of the Ferry Master’s Residence.

¬ Views look over the Kings Highway, Clyde River, Nelligen Bridge, and extend towards Buckenbowra State Forest.

¬ (for indicative visualisation see Section 7.8)

¬ This viewpoint sits directly atop the proposed rock cut adjacent to the Kings Highway. New cuttings and vegetation would be partially visible from the viewpoint.

¬ The proposed bridge, highway realignment, and reconfiguration to Maisies Lane would be visible in the distance

0-200m M L M-L

¬ The short range views of the Kings Highway would be screened behind proposed revegetation on the rock cuttings.

¬ From this vantage point, there are views of the new bridge as it meets the western riverbank. Updated rock cuttings and feature planting at the highway’s intersection with Maisies Lane would also be visible. However, fine detail would be obscured by the distance between V3 and the western bank.

¬ Vegetation on opposite side of the road would be removed to accommodate road widening improving river views and any new vegetation would be selected to ensure the retention of existing views.

V4

¬ Looking east towards the eastern bank of the Clyde River from the vantage point of the existing abutment. (It is anticipated that the abutment would be salvaged and rehabilitated as a viewpoint and extension of the adjacent parklands).

¬ (for indicative visualisation see Section 7.8)

¬ V4 provides clear views south and east over the Clyde River, as well as back towards Nelligen (which slopes up from the low point of the river).

¬ The proposed bridge would be highly visible from this location, however the proposed 72m retaining wall would be hidden behind the new abutment.

0-200m H H H

¬ The proposed bridge would run between 50m - 90m to the north of the existing alignment, away from the vantage point of the viewpoint.

¬ The removal of the existing bridge would open up views to the north, and the creation of a new lookout from the existing western bridge abutment would provide expansive views in all directions.

V5

¬ Looking east north-east from Maisies Lane down Braidwood Street towards the water’s edge.

¬ Close views of Nelligen’s main street, opening to longer views across the Clyde River as the terrain slopes away.

¬ Heavily screened views of the eastern approach of the Kings Highway, approximately at the location below the Ferry Master’s Residence on the opposite bank. 0-200m M L M-L

¬ From V5, the existing bridge is hidden behind buildings and vegetation, and can only be seen from very specific locations. The proposed bridge would run between 50m - 90m to the north of the existing alignment, and would be virtually invisible from the viewpoint.

¬ The intersection upgrade at Maisies Lane would be partially visible, although the proposed works are similar to existing materials and would not significantly impact the character of the current view.

KEY: Neg = Negligible VL = Very Low L = Low M-L = Medium Low M = Medium M-H = Medium High H = High

V1 V2 V3 V4 V5

57

7.5.1 DESCRIPTION

The Secondary VCZ has been determined as the area between 200 - 400 metres from the proposed works.

This zone covers a greater extent of the Clyde River, incorporating two viewpoints to the north and three to the south of the proposal. These riverside viewpoints provide an obstructed view of the proposed bridge, albeit from a distance that would make it difficult to distinguish detail.

To the west of Nelligen’s shoreline, the terrain gradually ascends. This higher ground provides intermittent views over and between the residential properties towards the river and proposed works.

The Secondary VCZ also captures the intersection of Bridge View Road and the Kings Highway, and would provide views of the reconfiguration of the highway at this point (V6). To the southeast of this point, the tie-in location would be visible marking the extend of works.

7.5.2 VIEWPOINTS

Five key viewpoints have been identified within the zone due to their proximity to the proposal (refer Figure 7.3). The viewpoints are:• 6: Kings Highway at Bridge View Road• 7: Clyde River off Bridge View Road• 8: Big4 Nelligen Holiday Park• 9: Nelligen village from Runnyford Road.• 10: Clyde River ; River Users

General characteristics of each of these viewpoints are provided in Table 7.3.

7.5 SECONDARY VISUAL CATCHMENT ZONE

Figure 7.3: Secondary landscape catchment zone

Artwork: SMM


Table 7.3: SECONDARY VISUAL CATCHMENT ZONE IMPACT ASSESSMENT

VIE

WPO

INT

NO

.

VIEW LOCATION & ASPECT ELEMENTS OF PROPOSAL POTENTIALLY VISIBLE DIS

TAN

CE

TO

PR

OPO

SAL

(M

)

VIS

UA

L SE

NSI

TIV

ITY

MA

GN

ITU

DE

OF

VIS

UA

L EF

FEC

T

OV

ERA

LL

RAT

ING

OF

VIS

UA

L IM

PAC

T

DESCRIPTION / COMMENT

V6 ¬ Looking west along the historic Old Nelligen

Road alignment from the intersection of the Kings Highway and Bridge View Road.

¬ Limited view by dense vegetation across on the other side of the highway.

¬ Pavement widening and intersection reconfiguration at Bridge View Road.

¬ To the north the highway disappears as it rounds the corner towards Old Nelligen Road. To the south the proposed highway ties into the existing alignment.

200-400m M L M-L

¬ The proposed works largely tie into the existing alignment from this viewpoint.

¬ Due to the anticipated traffic increase at Bridge View Road, the proposal calls for road widening to allow eastbound vehicles to safely turn off the Kings Highway without impeding the flow of traffic.

V7

¬ Looking northwest across the Clyde River from the residential properties adjacent to Bridge View Road towards Nelligen.

¬ New bridge, including concrete piers, western abutment, southern parapet, and guard rails.

¬ The western abutment would be partially screened by the remnants of the existing abutment, as well as estuarine vegetation.

200-400m M L M-L

¬ The proposed bridge would run between 50m - 90m to the north of the existing alignment, away from the vantage point of the viewpoint. The new structure would still be visible, however it would be more visually recessive than the current bridge.

¬ Removal of the existing bridge and revegetation of the riverbank would screen views of the proposed abutment from the south.

V8

¬ Views to the southeast down river of Big4 Nelligen Holiday Park towards Nelligen.

¬ This view is most prominent from the shoreline and from the elevated holiday residences.

¬ Elements visible from the shoreline include the new bridge including concrete piers, eastern abutment, northern parapet, and guard rails. The proposed western retaining wall and abutment would be partially screened by the wetland vegetation.

200-400m M M M

¬ The proposed bridge would shift to the north of the existing alignment, closer to the Big4 Nelligen Holiday Park. As a result, the new structure and associated road works would become more visually prominent than the current situation.

¬ From the central lawn of the holiday park, the proposal would be screened by shoreline vegetation. Views of the bridge would be most prominent from the shoreline.

V9

¬ Looking northeast from the vicinity of Nelligen Street and Currowan Place.

¬ Owing to the sloping topography, partial views of the bridge and river can be seen over the residential properties.

¬ Partial views of the new bridge, including concrete piers, western abutment, southern parapet, and guard rails.

200-400m L L L

¬ Movement of the existing alignment to the north would further obscure views of the proposed works.

¬ Existing vegetation would continue to screen views as it matures over time.

V10

¬ Views to the southeast down river toward the western abutment of the existing alignment

¬ The new bridge would be constructed in front of the existing bridge with elements, such as concrete piers, the eastern and western abutments, northern parapet, and guard rails, visible from the Clyde River. The foreshore areas would also be visually impacted where the bridge approaches the abutments, requiring the removal of some existing vegetation. The proposed western retaining wall and abutment would be partially screened by the existing wetland vegetation, as well as proposed screen planting adjacent to the abutment.x

200-400m M M M

¬ The proposed bridge would shift to the north of the existing alignment, closer to this viewpoint. As a result, the new structure and associated road works would become more visually prominent than the current situation.

¬ From the Clyde River, the proposal western abutment would be partially screened by existing shoreline vegetation, as well as, proposed screen planting.

¬ Existing vegetation would continue to screen views as it matures over time.

V6 V7 V8 V9 V10

59

7.6.1 DESCRIPTION

Road user views have been assessed in order to better understand the visual changes which would be experienced as a result of the proposal. The views and visual experience of road users need to be carefully considered in order to promote a visually attractive, stimulating and safe experience for the motorist. The relationship between road user views and urban design can improve this driver experience and contribute to a ‘sense of place’.

The road user would encounter distinct visual experiences on the proposal, which is summarised as follows (as a driver moves from east to west):• dense forest on either side of the highway, with the terrain sloping away from

the road providing screened views through the canopy• moments of enclosure as the driver passes through sections of steep rock

cuts• sudden and expansive views over the Clyde River towards Nelligen as the

driver emerges from the forest onto Nelligen Bridge• new feature planting to indicate the entrance to the village• continuation of the highway along the existing alignment, with upgraded rock

cuts to the south and intermittent views of the wetlands to the north.

7.6.2 VIEWPOINTS

Tie-ins

The road user experience at the eastern and western tie-ins would be slightly impacted by the proposal. The new works maintain the existing alignment and spatial conditions of the Kings Highway at these points, resulting in a minimal change to the current landscape character.

Batemans Bay Cycad Forest

The road user experience within the forested sections would be similar to the existing highway condition, in that the forest would visually enclose the road. In certain locations, this sense of enclosure would be modified due to larger cuttings and fill embankments. Existing views would also be screened by revegetation at the closure of Thule Road.

7.6 ROAD USER VIEWS

Nelligen Bridge

The road user experience on the approach to the bridge would be modified slightly by the larger turning radius. Current expansive views over the Clyde River would remain as one crosses the bridge, despite the slight shift in alignment. Clear views of Nelligen would be altered as drivers would now approach the village from an oblique angle.

Whilst long-distance views would be maintained when moving across the bridge, there would be a corresponding reduction of detailed foreground visibility due to the bridge rail barrier infrastructure and shared path on the southern side.

Nelligen

The road user experience at the intersection of Maisies Lane would be impacted by the propsed dog-leg turn. New feature planting would indicate the turn-off for Nelligen, as well as screen the highway from existing residences. This turn-off would follow on extension of the current alignment of Maisies Lane around the existing rock cut.

Plate 7.1: Eastern tie-in

Plate 7.2: Western tie-in

Source: SMM

Source: SMM


7.7.1 SUMMARY OF VISUAL IMPACT RATINGS

The visual impact assessment of the proposal described above represents a qualitative assessment based on Visual Catchment Zones, long-range viewpoints and road users of the proposal. Table 7.4 summarises the assessment results:Table 7.4: VISUAL IMPACT ASSESSMENT SUMMARY

VCZ # SENSITIVITY MAGNITUDE VISUAL IMPACT

Primary Zone: 0-200 m

1 Moderate Moderate Moderate2 Moderate Moderate Moderate3 Moderate Low Moderate-Low4 High High High5 Moderate Low Moderate-Low

Secondary Zone: 200m-400m

6 Moderate Low Moderate-Low

7 Moderate Low Moderate-Low


9 Low Low Low


7.7 SUMMARY OF VISUAL IMPACTS

7.7.2 OVERALL STUDY AREA IMPACTS

The proposal would have an impact on views in and around the study area. While the works, for the most part, are to take place in an established road corridor, they would impact on all Visual Catchment Zones (VCZ) to some degree, with the greatest impact being on motorists within the Primary VCZ and the Clyde River valley.

The proposed roadworks largely retain the existing alignment, with minor adjustments that would upgrade the highway to current standards. The proposed bridge would alter the experience of crossing the Clyde River heading towards Nelligen, however this new approach would be demarcated by feature planting and upgraded intersection configurations.

The overall visual impacts would be moderate to low depending on the range from which the proposal is viewed, as well as the components of the proposal that are visible from each viewpoint. These can be broadly described as follows:• Views within the Primary VCZ of new exposed rock cutting faces, new

bridge infrastructure features, adjusted road pavement and additional safety barriers would have a moderate impact as many of these features are already experienced by the road users but the alignment of these features would be different.

• Views from Secondary VCZ viewpoints are, for the most part, similar to existing conditions and are unlikely to have significant impact. Retaining walls and bridge abutments would likely have moderate to low impact as a result of the distance from the viewer and screening by existing landform features and vegetation.

Refer Section 4 & 8 for urban design principles and mitigation strategies.

61

7.8.1 LANDSCAPE PHOTOMONTAGES

The following pages depict photomontages of the potential visual impacts rendered by the proposal from two viewpoints:

• Viewpoint 3: Ferry Master’s Residence looking west over the Clyde River (refer Plates 7.3 and 7.4)

• Viewpoint 4: Wharf Street looking east along the southern edge of the existing bridge (refer Plates 7.5 and 7.6)

These visualisations are artist’s impressions of the proposed structure and bridge elements in the context of the existing landscape. They serve to indicate the scope and extents of potential visual impacts to landscape character in the vicinity of the study area

7.8 LANDSCAPE PHOTOMONTAGES


Plate 7.3: Existing view from Viewpoint #3: Ferry Master’s Residence looking west over the Clyde River

Source: SMM

63

Plate 7.4: Proposed view from Viewpoint #3: Ferry Master’s Residence looking west over the Clyde River

Source: SMM and Spatial Media

Reconfigured roadway and intersection at Maisies Lane

New paved interpretive lookout area. Proposedpaths and handrails to be screened by feature planting.

New bridge


Plate 7.5: Existing view from Viewpoint #4: Wharf Street looking east along the southern edge of the existing bridge

Source: SMM

65

Plate 7.6: Proposed view from Viewpoint #4: Wharf Street looking east along the southern edge of the existing bridge

Source: SMM and Spatial Media

New bridge abutment to meet new alignment

New bridge


67

8 MITIGATION MEASURES & CONCLUSIONS

8.1 Overview 68

8.2 Mitigation Measures 68

8.3 Conclusion 68


8.2 MITIGATION MEASURES8.1 OVERVIEW

In order to generate a proposal outcome that integrates the engineering and performance objectives with urban and landscape design objectives, a two-stage process has taken place: • Iterative engineering and urban design running in parallel, which optimises the

integration of the road elements into the landscape.• Development of mitigation measures to further reduce the impacts of the

proposal’s road and associated structures and elements on areas adjoining the road corridor.

This process aims to produce a design outcome that has high visual quality, whilst also satisfying technical requirements. In order to achieve this, a range of mitigation measures must be incorporated into the proposal during the various stages of design, construction and ongoing maintenance.

These measures, when considered in combination and when implemented at the various stages, provide a robust urban and landscape design solution that protects and enhances the existing landscape character and visual quality of the Clyde River.

Mitigation measures are treatments that are recommended to reduce the impact of the proposal. They include ways to lessen the visual effect of the proposal itself and also to identify treatments near critical view areas to reduce the visual impacts of the proposal.

Mitigation measures also aim to reduce impacts on existing landscape character through consideration of existing site features, cultural and environmental heritage. These mitigation measures are also designed to improve environmental conditions or lesson the physical impacts on the environment.

Therefore it is possible to implement these measures across all facets of the proposal, particularly road elements design, earthworks design and revegetation methodologies.

Table 8.1 summarises the means by which the mitigation measures would be incorporated into the proposal.

Refer to Section 4 of this report for urban and landscape strategy plans and concept plans for graphic representation of these recommendations.

Refer to Section 5 of this report for landscape implementation strategies to assist with visual impact mitigation.

8.3 CONCLUSION

The proposal for the adjusted alignment of the Kings Highway would involve the partial realignment of the existing road and construction of a new bridge within a sensitive riverine setting. These works involve moderate earthworks (cutting and embankment), the introduction of new roadside elements and planting, and the demolition and removal of the existing Nelligen Bridge. The proposal would tie in to the existing highway in two locations combined with the new bridge across the Clyde River, providing a more streamlined and safer driving experience on this section of the Kings Highway.

The urban design principles and objectives take into account both the Nelligen village area and broader Clyde River valley and surrounds. The incorporation of the proposed landscape treatments would assist with integrating new works into the existing landscape character areas.

The proposal would moderately impact the existing character of the place, however these changes are consistent with other sections of the Kings Highway and are to be expected from a proposal of this type. Mitigation measures, once implemented, would assist in reducing local resident and road user awareness of these changes.

Overall the proposal would have moderate visual impact when viewed from locations within 400 metres from the works, with substantially less impact from viewpoints further afield. The road user experience would be improved in terms of safety, uniformity and views due to elevation above existing vegetation and position away fro the existing escarpment.

The proposal fulfils the identified urban design objectives and principles, when assessed in combination with the proposed mitigation measures.

69

Table 8.1: SUMMARY OF MITIGATION MEASURES

STRATEGY & ISSUE STAGE RECOMMENDATION RATIONALE

Quality of structures:

¬ The new bridge across the Clyde River valley would be a large structure but is visually consistent with the existing structure when seen from local viewpoints.

Design ¬ The proposed bridge across the Clyde River would be designed to the standard assigned to this category of bridge as defined in the RMS Bridge Aesthetics guidelines

¬ The proposed bridge over the Clyde River, whilst only partially visible from the road user perspective would be highly visible from several local viewpoints.

Construction ¬ Construction work zones are to be limited to areas adjacent to the proposed works

¬ Concrete form work is to be a high quality, with parapets precast or cast-in situ and piers formed with accurate tapers and clean edges.

¬ Impacts to existing riverine landscape and ecosystems are to be minimised to allow the protection of existing riparian vegetation, establishment of new vegetation and protection of habitat

¬ Quality construction techniques and outcomes improve the overall perception of the bridge from the road.

Maintenance ¬ Bridge maintenance is to be provided for in terms of sufficient access to bridge bearings in accordance with RMS requirements in order for the bridge to be maintained correctly. Bridge access is to be well-integrated into the bridge abutments.

¬ High quality construction, materials and visual attractiveness of the bridge structure would reduce likelihood of vandalism, increase longevity of structure.

Integration of earthworks design with existing landform:

¬ The proposal would involve earthworks including cuttings, fill embankments and retaining walls to achieve the necessary horizontal and vertical alignments.

Design ¬ The potential visual impact of these earthworks can be minimised by careful design that integrates with adjoining landform.

¬ This would be achieved through rounding of the top of cut batters, tailing-off of cut batters and a gradual flattening of grades at ends of fill embankments in order to avoid sharp transitions at ends. The design of retaining walls to utilise visually recessive materials and colours, as well as, screen planting to minimise visual dominance.

¬ Integration of existing and proposed landform provides a more visually appealing urban design outcome and reduces visual abruptness of the proposal.

Construction ¬ Retaining walls would be constructed of precast units in order to minimise the construction footprint and removal of existing vegetation. Provide screen planting below walls and utilise visually recessive materials in order to minimise visual dominance.

¬ Construction techniques would be in accordance with design so that urban design and visual impact mitigation objectives are met.

Maintenance ¬ Ensure access to the wall is provided so that the structure and materials can be maintained. ¬ Maintenance of structures improves longevity of the structure and the overall perception by road users and local residents.

Retention of existing vegetation:

¬ The proposal would involve the removal of some relatively small areas of vegetation likely to be visible from the road and unlikely to be visible from surrounding viewpoints.

Design ¬ Design the proposal to avoid impact to prominent trees and vegetation communities where possible

¬ Existing threatened species are to be retained and protected wherever possible

¬ Retaining walls and batters to be steepened to grades suitable for the proposed surface treatment in order to minimise the overall footprint of the proposal

¬ Design water quality structures and drainage lines to avoid existing vegetation where possible.

¬ Retention of existing vegetation greatly assists with integrating the new work with the existing landscape, hence reducing visual impacts of the proposal

¬ Retention of existing vegetation also helps contribute to biodiversity.

Construction ¬ Work areas to be clearly defined, managed and supervised to ensure vegetation loss is minimised. ¬ Construction activities can increase impacts on existing vegetation where improperly managed.

Maintenance ¬ Clear zones to be kept to the minimum required in order to allow regeneration to occur, particularly in parts of the proposal where regeneration would assist with screening.

¬ Occasionally local or regional clear zone requirements may vary from standard RMS procedures. Existing precedents may be considered where adopting the minimum clear zone requirements would assist with establishment and regeneration.


SUMMARY OF IMPACT MITIGATION MEASURES (continued)

STRATEGY & ISSUE STAGE RECOMMENDATION RATIONALE

Revegetation and planting methodologies and contingencies:

¬ The proposal would involve areas of planting and revegetation.

Design ¬ Utilise a series of methodologies to ensure best outcomes in specific locations eg. riverine wetlands and lowland forests

¬ Revegetation methodologies have been designed to make use of local conditions and the limited availability of materials.

Construction ¬ Existing vegetation where removed to be re-used on the proposal in the form of mulch added to planting and areas; and coarse woody debris used creek lines (downstream of structures).

¬ Contractor education on specialised revegetation methodologies is critical from the outset of the construction phase of the proposal

¬ Consultation with the community is also critical so that Day 1 and long-term revegetation success expectations can be managed.

Maintenance ¬ Discuss specific maintenance procedures with RMS teams early so that regimes are specific to the revegetation methodologies employed

¬ Raise awareness that revegetation methods may take time and would not provide Day 1 impact in locations where this method is utilised.

¬ Maintenance regimes (or lack of maintenance in some instances) is critical to ongoing success of the revegetation methodologies employed on the proposal.

Minimisation of road furniture and signage:

¬ Fencing, barriers and signage would be required as part of the proposal and have the potential to clutter the visible landscape.

Design ¬ Signage locations are to be coordinated with other roadside elements including structures, furniture, fencing and landscape treatments

¬ Bridge barriers would be a half ‘Type F’ with a double rail which would continue along the top of the retaining walls. Barriers would be ‘W’ beam due to spatial constraints and safety requirements.

¬ Reduction and integration of these elements would help to reduce visual clutter.

Construction ¬ Look for opportunities to minimise designed signage, particularly where changes to the alignment have occurred during construction.

¬ Reduction and integration of these elements helps to reduce visual clutter.

Maintenance ¬ Maintain signage and other furniture elements in good order so that the road remains well-presented and a reflection of the local community.

¬ High quality materials and visual appearance of roadside elements would reduce likelihood of vandalism, increase longevity and encourage local ‘ownership’.

Use of “soft engineering” and well-integrated drainage facilities:

¬ Drainage channels would be implemented at the top of the proposed embankment cuttings

Design ¬ Visible roadside channels would be vegetated or rock lined

¬ Concrete lined channels would be avoided as much as possible. Where they are to be used, the concrete would be coloured and/or heavily roughened.

¬ Drainage channels would be designed to visually integrate with their surroundings as much as possible.

Construction ¬ Prepare drainage prototypes off-site or in non-visible areas. ¬ Establish criteria for drainage linings that are acceptable from a visual perspective.

Maintenance ¬ Maintain drainage structures where required noting that revegetation and darkening are emphasised as a positive outcome from an urban design perspective.

¬ Ongoing settling-in and weathering would assist with visual integration.

Retention of vistas and visual links between local landmarks and elements:

¬ Views are important to local residents and provide interest to road users.

Design ¬ Planting of riverine species in the Clyde River valley would maintain consistent views along the shoreline.

¬ Local views assist with creating a ‘sense of place’ for the road user

¬ Maintaining local vistas assists with retaining existing cultural landscape values. Existing bridge abutments can be integrated into adjacent parklands and transformed into vantage points over the river.

Construction ¬ Ensure trees and revegetation areas are in conformance with the drawings and look for opportunities to ‘ground-truth’ planting locations for further adjustment.

¬ Existing site features not always exactly replicated in site surveys.

Maintenance ¬ Maintain important vistas during maintenance regimes

¬ Do not remove revegetation associated with screening or headlight glare unless within clear zones.

¬ Regeneration would occur within landscape revegetation areas and these areas would evolve over time.

Retention of local transport connections:

¬ Local connectivity is critical to maintaining local community functions and activities.

Design ¬ Maintain connectivity principles throughout design development. ¬ Ensure local residents can easily access their properties and maintain local road network.

71

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