13.4 Assessment of potential construction impacts
This section assesses visual impacts on receivers during construction. An overview of visual impacts is provided, including the impact assessment ratings for sensitivity and magnitude at each facility. Site layouts are indicative and dimensions of structures and buildings mentioned in this section, including noise walls, hoarding, fences and acoustic sheds, would be confirmed during detailed design. Receivers with views of construction ancillary facilities and construction activities could include:
- Residents that adjoin and/or have views of the project
- Workers in commercial properties that adjoin and/or have views of the project
- Road users and pedestrians
- Users of recreation areas/reserves with views of the project.
Visual impacts during construction would result from the introduction of construction ancillary facilities into the existing landscape. This would include night lighting at sites that involve tunnelling activities or that support tunnelling activities.
Construction activities that would take place at the construction ancillary facilities are discussed in Chapter 6 (Construction work). In general, visible construction activities would include (where required):
- Vegetation removal
- Noise barriers/hoarding/fencing
- Heavy and/or light vehicle access potentially 24 hours a day, seven days a week
- Staff amenities buildings
- Workshops and storage containers
- Stockpile and laydown areas
- The operation of plant and equipment, including cranes
- Lighting for night-time works
- Water storage tanks
- The construction of infrastructure for the operation of the project.
The potential night lighting impacts at the relevant construction ancillary facilities are also assessed.
Impact ratings for visual and night lighting impacts during construction are included in the summary tables for each construction ancillary facility assessed in this section. A detailed explanation of these impact ratings is provided Appendix O (Technical working paper: Landscape and visual impact).
The detailed design of construction ancillary facilities would include the consideration of CPTED principles, which are outlined in section 13.5.8.
13.4.1 Visual impacts on sensitive receivers
Representative receiver locations have been identified at each construction facility and potential visual impacts on these receivers are summarised in Table 13-5. The location of representative receiver locations is shown in Figure 13-5 to Figure 13-16.
Table 13-5 Summary of construction visual impacts on sensitive receivers
13.4.2 Construction lighting impacts
Potential night lighting impacts on receivers at representative receiver locations for each construction ancillary facility are summarised in Table 13-6. It is anticipated that construction works at The Crescent civil site (C6), the Victoria Road civil site (C7) and the Iron Cove Link civil site (C8) would be carried out during standard daytime construction hours and therefore impacts on night lighting have not been assessed at these locations. The location of representative receiver locations is shown in Figure 13-5 to Figure 13-16.
Table 13-6 Summary of construction lighting impacts.
13.5.6 Mainline tunnels
A concept for in-tunnel experience would be prepared as part of the UDLPs for the project (refer to section 13.5.9). The in-tunnel experience for the M4–M5 Link would be developed to be consistent with and to complement the adjoining M4 East and New M5 tunnels, and in accordance with the following principles:
- Creation of landmark or site specific/unique experiences
- Use of optimal lighting / adaptable luminance
- Creation of subtle variations to keep drivers alert
- Measures to break up long continuous travel distances
- Shifting gradients and alignments to avoid monotony
- Providing clear speed and distance references
- Legible wayfinding.
13.5.7 Remaining project land
Subject to future detailed design and the requirements of the project, parts of the project footprint not required for operational infrastructure and/or landscaping may be contemplated for separate future redevelopment. In some instances, areas of land may also be retained by Roads and Maritime for future (separate) road infrastructure projects. Where this is the case, the land would be rehabilitated and stabilised in preparation for the potential future use. This land is identified as remaining project
Remaining project land would be subject to the provisions of a Residual Land Management Plan that would be prepared in consultation with the relevant council and would identify (and consider), but not be limited to:
- Identification and illustration of all remaining project land, including the location, land use characteristics, size and adjacent land uses
- Identification of feasible uses for remaining project land including justification for the selected use
- Timeframes for implementation of the actions in relation to the identified feasible uses.
Future development would be subject to separate development assessment and approval. The project would not rezone or consolidate remaining project land and therefore there would be no changes to land use zoning for future development.
In addition, remaining project land around the Wattle Street interchange at Haberfield and the St Peters interchange at St Peters would be managed to be consistent with the M4 East and New M5 projects’ respective Residual Land Management Plans and UDLPs, including the M4 East Legacy Project (as required by the conditions of approval for the M4 East and New M5 projects). The project would not impact on the implementation of these plans, but may impact the timing in which in the plans are carried out.
Further discussion regarding remaining project land is provided in Chapter 12 (Land use and property).
13.5.8 Crime Prevention Through Environmental Design
Principles of CPTED would be considered and incorporated into the urban design through the preparation of the UDLPs for the project. Key CPTED principles to reduce opportunities for crime are outlined below:
- Surveillance: the public realm and buildings should be designed and managed to maximise the potential for passive surveillance
- Legibility: the public domain should be designed, detailed and managed to make them easy to navigate and understand for users, especially pedestrians and cyclists, without losing the capacity for variety and interest
- Territoriality: security should be supported by designing and managing spaces and buildings to define clearly legitimate boundaries between private, semi-private, community group and public space
- Ownership of the outcomes: a feeling of individual and community ownership of the public realm and associated built environments must be promoted to encourage a level of shared responsibility for their security
- Management: the public realm should be designed and detailed to minimise damage and the need for undue maintenance, without undermining the aesthetic and functional qualities that make the places attractive to the community. Systems of both regular and reactive maintenance and repair should be implemented to maintain the quality of the places. A regular auditing system of CPTED issues in the public domain should be implemented
– The public domain should be designed and managed to reduce or limit risk from assault by providing well-lit, active and overlooked places and pedestrian and cyclist systems and routes to important places
– The design and management of places should avoid creating or maintaining hidden spaces close to pedestrian/cyclist travel routes in the public realm, in ways that remain consistent with the purpose of the place
– The design and management of the public domain should provide a variety of routes and other ways to avoid potential or actual problems
– The pursuit of safety should be delivered in ways consistent with the purpose of the place.
During detailed design, specific design measures at surface operational infrastructure would be identified to prevent crime.
13.5.9 Urban design and landscape assessment
The urban design and landscape works that would be carried out by the project would be documented in UDLPs. UDLPs would be prepared in consultation with stakeholders and the community prior to the commencement of permanent built surface works and/or landscape works and would present an integrated urban design for the project.
The concepts and principles outlined in the UDLPs would be developed into a detailed design for operational project infrastructure. The detailed design would be consistent with the project urban design principles (see section 13.2.2) and would include:
- Final land use for UDLP land
- Final design and material composition for built form structures
- Final landscape design
- Final heritage interpretation plan
- CPTED review of design (see section 13.5.8).
A detailed review and finalisation of architectural treatment of the project operational infrastructure, including ventilation facilities, would be undertaken during detailed design. The architectural treatment of these facilities would be guided by ventilation facility performance requirements, the outcomes of community consultation and the urban design principles identified in section 13.2.2.
Landscaping works would be carried out adjacent to disturbed areas, around operational
infrastructure (such as ventilation facilities), and in areas of new open space that would be provided at the Rozelle Rail Yards and adjacent to Victoria Road at Rozelle.
Areas where permanent operational infrastructure is proposed have been reviewed against the urban design principles developed for the project, which are outlined in Table 13-2. The outcome of this assessment is provided in Table 13-23.
The review has been carried out using the concept design, including preliminary designs for the built form elements of the project. It is difficult at this early stage of the design resolution to be conclusive with regard to all of the required urban design elements. The structures and facilities that would be provided for the project such as ventilation facilities, tunnel portals and water treatment plans would be would be detailed in the UDLPs that would be prepared for the project. The built form structures and facilities would be designed to complement the surrounding context, with a materials palette that
draws on the materials and textures of the surrounding areas to be developed during detailed design.
The nature of the design process is iterative and will continue to evolve as various elements become realised in detail and better coordinated as part of the whole project. With this in mind, a number of project design commitments are provided to guide the continued development of the project in line with the mitigation measures provided in section 13.6.
Urban design elements proposed for the areas where substantial surface infrastructure is planned (around the Rozelle interchange and the Iron Cove Link) is discussed in more detail in Appendix L (Technical working paper: Urban design).
13.6 Environmental management measures
The detailed design and construction of the M4-M5 Link project would be managed to ensure the identified landscape and visual impacts are minimised by implementation of a range of general and specific measures which are outlined in Table 13-24.
The environmental management measures provided in Table 13-24 have been developed in order to:
- Avoid, reduce and manage identified potential landscape and visual impacts during construction and operation
- Provide substantial mature and semi-mature street-tree planting for screening and shade, and mixed sizing of planting where stratification of the canopy is desired
- Provide high quality finishes to buildings and vent facilities to facilitate long term durability of the design for effect with minimal maintenance, eg use of hard rock rather that concrete with a pigment which may fade over time
- Improve open space to offset additional infrastructure, eg provision of street trees to adjoining local streets affected by the project
- Improve active transport links to reduce reliance on motorway and local roads for short journeys.
Table 13-24 Environmental management measures – landscape and visual