Section C Sector Design Concepts C7 Sector 7 Great North Road Underpass 6 6 6 C7. Existing situation Sector 7 refers to the cut and cover section of the project linking the northern end of the deep tunnels (Sector 8) with the northern portal at Waterview Park, crossing beneath Great North Road. For the purposes of urban and landscape design mitigation it includes Waterview Primary School. C7.. Movement and connectivity An existing pathway extends through the Oakley Creek Esplanade (beginning in Sector 5 and terminating at Harbutt Reserve). There are no formed connections to this walkway in the sector C7..3 Urban form Waterview is a post-war state housing suburb with single and two storey dwellings. The coastal edge and the North-Western Motorway (SH6) provide strong boundaries to the area to the north. There is a lack of commercial heart The existing houses between Great North Raod and Waterview Primary School currently buffer the school and the kindergarten from traffic noise. Their demolition for motorway construction will remove this buffer and also widen the urban gap between the community and the Point Chevalier neighbourhood centre. An existing off road cycleway along the eastern side of Great North Road connects to the SH6 cycleway Great North Road provides a hard, traffic dominated edge to the residential area of Waterview and severs it from Oakley Creek to the east Pedestrian and cycle amenity along Great North Road is poor. Council has identified a substandard section of the SH6/SH0 cycleway link along Great North Road (between the existing shared path and Phyllis Street Reserve) C7..4 Open space amenity Saxon Reserve edged by Saxon Street, Alfred Street and Oakley Avenue is the only other public space asset (than Waterview Park) readily available to the local community. It contains a playground. The Reserve is limited in its usefulness and flexibility by its small size Limited crossings over Great North Road to the Oakley Creek network and thence to the facilities in the Unitec campus restrict easy access to open space. Waterview is severed from the Point Chevalier shops by SH6 and the associated urban gap. C7.. Landscape, planting, views Oakley Creek runs through a deeply incised valley west of the Unitec Campus. The topography and vegetation along the creek contributes to the strong sense of enclosure of the creek corridor itself. Riparian planting forms a green backdrop to the immediate urban context. A 6m high waterfall is an unusual and distinctive feature Street trees and planting in front gardens on streets running off Great North Road create a well vegetated suburban neighbourhood character Waterview Primary School, between Oakley Avenue and Herdman Street, has views towards the proposed interchange works. Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00 C 6
Western Ring Route Waterview Connection Photo 7 Photo7 Photo7 5 Photo7 3 Figure C-7.: Sector 7 existing plan Photo7 4 C 6 Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00
Section C Sector Design Concepts Figure C-7.: Photo 7 View from Waterview Primary School north towards proposed interchange Figure C-7.3: Photo 7 Oakley Creek walkway, showing recent revegetation planting and pathway works Figure C-7.4: Photo 7 3 View from Herdman Street towards Waterview Primary School Figure C-7.6: Photo 7 5 Saxon Reserve Figure C-7.5: Photo 7 4 Six metre high waterfall on Oakley Creek Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00 C 63
Western Ring Route Waterview Connection C7. Design concept C7.. Landscape, planting, views C7..4 Structures C7..34 Open space amenity C7.. Movement and connectivity No long-term change is proposed to the functioning of Great North Road nor the adjoining streets, as the cut and cover tunnel runs under this sector While there will be impacts on Great North Road and the cycleway during construction, all existing connections will be maintained The project does not preclude Auckland City Council from upgrading the substandard section of the cycleway network on Great North Road A new pedestrian bridge (Oakley Bridge), while not part of the core project, could support a link between the Waterview Community and the sportsfields and other open spaces wtihin Unitec, and enable an extension of the off-road cycleway. Landscape treatment will partially screen the ventlation building. C7..3 Urban Form Housing along Great North Road will be removed to accommodate the cut and cover section of the tunnel. The proposed single storey ventilation building in Option A (refer Figure C-7.8) is of a similar height and depth to the housing stock, but is a much longer structure, extending across 7 residential lots. The building will screen the school and its grounds from traffic noise along Great North Road. Ventilation building and stack Options were explored for locating the ventilation building and stack. Option A is the option to be consented and comprises a partially buried ventilation building with an aboveground section running along Great North Road between Herdman Street and Oakley Avenue. The stack is to the west and slightly south of the ventilation building, between it and the school (see photomontages and plans and sections following in Figures C-7.7 C-7.). The viewpoint for the before and after visualisations is shown on the location plan aerial opposite. An alternative option (Option B) locates the ventilation building fully underground and the stack within Oakley Reserve. This option was developed because of its reduced visual impact and because it enables a future treatment of the western Great North Road edge more in keeping with the neighbourhood scale, and more flexible in terms of future uses. Option B is illustrated in Figures C-7. C-73). Auckland City Council and the community requested the NZTA to investigate a new pedestrian bridge (Oakley Bridge) connecting Waterview and Unitec to enable comunity use of the sporting and open space facilities. While not part of the core project, the bridge could be pursued in future by ACC in partnership with Unitec as part of their campus planning. BEFORE AFTER Figure C-7.7: Artist s impression of ventilation building and stack Great North Road option (Concept Option A) C 64 Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00
Section C Sector Design Concepts Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00 C 65 Approximate location of cut tunnel mouth 470 400 408.4 Great North Road 70000 School Grounds South bound lanes below 470 400 408.4 North bound lanes below Specimen tree planing Redevelopment land Service vechicles IN Oakley Ave Redevelopment land Redevelopment land Specimen tree planing Specimen tree planing Vent location A-65D : 000 Plan Option 4 - Location plan Service vechicles OUT Herdman Street Specimen tree planing Figure C-7.8: Ventilation building location plan (Concept Option B)
Western Ring Route Waterview Connection GREAT NORTH ROAD Figure C-7.9: Ventilation building Great North Road (Concept Option A); basement level C 66 Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00
Section C Sector Design Concepts GREAT NORTH ROAD Figure C-7.0: Ventilation building Great North Road (Concept Option A); ground level plan Figure C-7.: Ventilation building Option A; cross section Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00 C 67
Western Ring Route Waterview Connection Oakley Bridge W AA Buried Vent Station V 3930 Great North Road 4045 Oakley Avenue Cut & Cover Bored Tunnel Alford Street Alverston Street Figure C-7.: Ventilation building Oakley Reserve location plan (Concept Option B) SITE PLAN C 68 Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00
Section C Sector Design Concepts 3900.000 North Bound Portal South Bound Portal Stairs Smoke Smoke exhaust exhaust Inlet Inlet Handrail Air Flow Transition Wall Exhaust Inlet Inlet Access hatch to below Air Flow Removable handrail to perimeter of access hatch InletAttenuator 3930 Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00 C 69 Smoke Fans Stacked Exhaustfan pressure wall Air Lock 4000.000 Air Flow Air Flow Transition wall 4000.000 Outlet Attenuator Exhaust Shaft A-65E 65 66 W AA 5 00' 00" 5 00' 00" 67 Stair R 6700 5600 0000 3897 5 00' 00" 4045 FAN ROOM LEVEL W UP AA A-65E Lift Lift Stair Ramp 80 8 Generator Generator Lifting beam over Stair Store Store 70 Control Control Room Room Lifting Beam Transformer Transformer Store Store 7 78 79 77 76 High High Voltage Voltage Switch Switch Room Room Low Voltage Voltage Switch Switc h Room Room 7 A-65E 74 73 75 V High High Voltage Voltage Switch Switch Room Room Figure C-7.3: Ventilation building Concept Option B plans: Fan Room level and Service level FFL 4950 Top of Stack FFL 700 Option 5 Roof FFL 700 Option 5 Service FFL 00 Option 5 Plant SERVICE LEVEL PLAN Attenuator 7 7 8 0 7 5 5000 min 400mm soil cover Existing ground dashed Attenuator Lifting Room Transformer Access Store Control Room Air intake Cut and Cover Tunnel 8000 Figure C-7.4: Ventilation building Concept Option B long section
Western Ring Route Waterview Connection Oakley Bridge has been proposed by the community and ACC to support pedestrian movement between Waterview and the Unitec campus. Like the Phyllis Bridge, it should be a simple, elegant structure with minimal impact on the sensitive creek environment. The design concept has it bridging Oakley Creek at a high level for flat walking grades and maximum ease of travel / accessibility 4000.000 A A A3 A4 A5 A6 4000.000 B 3D VIEW 6 3D VIEW 3 B 3D VIEW 4 3D VIEW 5 3D VIEW 3D VIEW : 000 Plan _LEVEL A A A3 A4 A5 88000 A6 7500 7000 34000 7000 7500 000 000 CONCRETE ABUTMENT TIMBER DECKING SK-005 SK-00 3 SK-00 CONCRETE PILE CAP CONCRETE ABUTMENT B SK-003 B 3000 SK-003 SK-003 SK-003 3 : 500 Plan SK-005 SK-00 SK-00 UC PIERS FOOT PATH _LEVEL 000 000 03000 Figure C-7.5: Oakley Bridge location and concept plan C 70 Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00
Section C Sector Design Concepts 3D View 3D View 4 3D View 6 3D View 3 3D View 5 Figure C-7.6: Oakley Bridge 3D views showing possible future form and setting in the landscape 3D View Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00 C 7
Western Ring Route Waterview Connection Saxon Reserve will be extended as part of this project, to provide an area of open space to complement the reconfigured Waterview Park The urban design team developed a draft concept design (Figure C-7.8) to illustrate how the park might be extended and upgraded. Figure C-7.7: Saxon Reserve - existing plan Figure C-7.8: Saxon Reserve - concept plan C 7 Western Ring Route Waterview Connection Urban and Landscape Design Framework Beca Jasmax SBEL NZTA June 00