SH1 Western Belfast Bypass Transportation Assessment

Transcription

1 SH1 Western Belfast Bypass Transportation Assessment

2 WBB- Transportation Assessment i This report has been prepared on behalf of the NZ Transport Agency (NZTA). No liability is accepted by this company or any employee or sub-consultant of this company with respect to its use by any other person. This disclaimer shall apply notwithstanding that the report may be made available to other persons for an application for permission or approval or to fulfil a legal requirement. Prepared By Shelley Perfect Principal Transportation Engineer Opus International Consultants Ltd Christchurch Office 20 Moorhouse Avenue PO Box 1482, Christchurch Mail Centre, Christchurch 8140 New Zealand Reviewed By Telephone: Mike Davies Senior Transportation Engineer Facsimile: Date: 07/ 05/2014 Reference: 6DC Status: Final2

3 WBB- Transportation Assessment ii Contents Executive Summary Strategic Context Project Overview Traffic Volumes and Travel Time Traffic Models Traffic Volumes Travel Time Links and Intersections Linking the Bypass to the Northern Motorway Dickeys Road Johns Road/Dickeys Road Intersection Main North Road/Johns Road Southern Interchange and Groynes Drive Walking and Cycling Safety Traffic Management during Construction... 12

4 WBB- Transportation Assessment 1 Executive Summary The Western Belfast Bypass (WBB) will lead to significant positive effects at a local, regional and national level including: a safer, more convenient and efficient route for traffic consistent with the RoNS objectives significant travel time savings for strategic traffic travelling to Christchurch International Airport and destinations beyond, by bypassing the built up Belfast urban area an associated reduction in traffic volumes on the existing Main North Road and Johns Road corridors which will improve local access, safety and amenity in Belfast. Traffic volumes on Main North Road are expected to decrease from 37,000 vpd in 2013 to 22,000 vpd in 2016 with the Western Belfast Bypass (assumes no Northern Arterial in place which will reduce Main North Road volumes even further) the reduction in traffic along Main North Road will enhance options for improvement in public transport provision and improved pedestrian and cycling facilities an upgraded Groynes Drive that will provide enhanced pedestrian and cycling facilities through a shared pedestrian/cycleway path, road shoulders, pedestrian refuges (one on Johns Road adjacent to Groynes Drive) and safer access to subdivisions and business through provision of a flush median for turning vehicles. enables implementation of future development such as that described in the Belfast Area Plan. To mitigate any actual or potential adverse traffic effects associated with the construction period of the proposed WBB project, a Temporary Traffic Management during Construction Management Plan (TTMCMP) will be prepared.

5 WBB- Transportation Assessment 2 1 Strategic Context The WBB will provide a new limited access connection between the Christchurch Northern Motorway at the northern end and extending approximately 5 km to Johns Road near The Groynes entrance at the southern end, thus bypassing the urban area of Belfast on the northern edge of Christchurch. The WBB was included as part of the Roads of National Significance (RoNS) package announced by central government in 2009 and forms part of the Christchurch Motorways package within the Western Corridor group of projects (refer Figure 1-1). Figure 1-1: Roads of National Significance showing the Western Corridor and Western Belfast Bypass The Western Corridor connects the northern and southern Canterbury areas with Christchurch International Airport. It runs between Belfast in the north and the large industrial area at Hornby in the south. A significant proportion of the traffic on the western corridor is heading to and from Hornby or the airport. The corridor works are required for a number of reasons: Around 37,000 vehicles per day, among the highest for any road in Canterbury, use Main North Road through Belfast to enter and exit Christchurch. This number of vehicles, and in particular the trucks and heavy vehicles using the road, discourage walking and cycling and restrict options for public transport.

6 WBB- Transportation Assessment 3 As traffic volumes grow, congestion will become worse and safety and public health concerns will increase around the Main North Road/Belfast Area. There is insufficient capacity in the existing two-lane western corridor to absorb further traffic growth (note a significant length of the corridor has been 4-laned in recent years as part of the Western Corridor package of works). To ensure businesses based outside Christchurch are able to get their goods to and from the airport, commercial areas and industrial areas, the current road requires upgrading to reduce travel time, improve travel time predictability and improve safety. The Transport Agency has specific objectives for the Project which are directly relevant to this transport assessment: Enhance inter-regional and national economic growth and productivity Enhance access to key activity and industrial areas including Belfast Improve travel times and predictability of travel times on critical intra- and inter-regional connections between north of the city, Christchurch Airport and beyond Improve local access on to the existing network, safety and social amenity in the Greater Christchurch Urban Development Strategy (UDS) township area of Belfast, thereby giving effect to broader UDS outcomes for more sustainable land use and transport integration Ensure better access for public transport, walking and cycling in the UDS growth node of Belfast Reduce environmental effects by implementing new design standards Improve safety through development of new infrastructure to current standards and reduce exposure at existing points of potential conflict Preserve the long term function of the State Highway. The existing northern access to Christchurch passes through Belfast, which is a built up residential area with high traffic congestion, especially at the Main North Road / Johns Road intersection. People and goods needing to access Christchurch International Airport and destinations further west and south currently must pass through the Belfast urban area. The route currently experiences congestion and predicted growth in the north and west will place further demand on the western corridor.

7 WBB- Transportation Assessment 4 2 Project Overview The Transport Agency proposes to construct, use and maintain a motorway (4-lane median divided arterial road) extending the Christchurch Northern Motorway (SH1) to link with Johns Road (SH1), Christchurch. The WBB connects to the Northern Motorway north of Dickeys Road and travels across green fields to join Johns Road in the vicinity of The Groynes. SH1 traffic using the WBB will bypass the Belfast urban area. The WBB removes regional through-traffic and heavy vehicles destined for the Airport, Hornby and South, from the Belfast Urban area thus improving freight efficiency and reducing local-regional traffic conflicts. Figure 2-1: Overview plan Some key aspects of the project are summarised as: the bypass will be a 4 lane motorway (no access along the bypass) access to the bypass is from Johns Road to the north and the Northern Motorway to the north off ramps at Groynes Drive south of the bypass and at Main North Road north of the bypass the Waimairi walkway will remain open with realignment in a couple of locations and a subway to pass under the bypass Dickeys Road will remain open and Dickeys Road will go under the bypass Groynes Drive will be upgraded and go under the bypass the Groynes Drive/Johns Road intersection will be an upgraded T-intersection.

8 WBB- Transportation Assessment 5 3 Traffic Volumes and Travel Time 3.1 Traffic Models Traffic flows were extracted from the Christchurch Assignment and Simulation Traffic (CAST) Model as at December CAST is a validated SATURN traffic model for Greater Christchurch. It is widely accepted as currently being the most accurate large scale model of Christchurch travel patterns. It has been subject to a rigorous process of calibration/ validation and peer review to ensure that modelling forecasts are reliable. The growth forecasts have taken account of the changes brought about by the recent earthquakes. Model outputs are for the 2016 and 2026 year. 3.2 Traffic Volumes Table 3-1 presents the baseline 2013 traffic flows, together with the forecast with the project (WBB) as well as with and without the Northern Arterial (NArt) traffic flows in 2016 and A percentage change is shown to compare the traffic growth from the baseline 2013 traffic flows to the future 2016 year and the 2026 year. The 2016 year is a forecast year adopted by the model and is also close to the completion date for the WBB. The modelling forecast year is around 10 years post completion of the project. Table 3-1: Traffic Volumes from the Christchurch Assignment and Simulation Traffic (CAST) model Western Belfast Bypass Main North Road south of Dickeys Road SH1 Johns Road east of Groynes entrance 2013 AADT (from traffic counts) N/a 36,500 18, with WBB / no NArt 24,300 22,100 (-39%) 6,200 (-66%) 2026 with WBB / no NArt 30,700 26,200 (-28%) 7,600 (-59%) 2026 with WBB and NArt 22,700 10,200 (-72%) 7,300 (-61%) ( ) - % change from 2013 NZTA traffic counts The above table shows that the WBB will lead to a significant reduction in traffic along Main North Road. The potential future Northern Arterial will reduce the traffic flows even further. As part of a wider package of transportation measures (outside of the scope of this project) it is intended that Main North Road will serve as the main public transport (PT) spine with improvements to current bus lanes measures that can be supported with reduced future traffic volumes along this arterial. The reduction in traffic levels will also allow for improved pedestrian and cycling facilities along Main North Road. It is noted that the WBB and Northern Arterial Project (NArt) serve to relieve the existing Main North Road corridor which will then revert to a local arterial.

9 WBB- Transportation Assessment Travel Time Journey time assessments for the WBB show for the 2016 year 2 to 4 minutes per vehicle is saved by using the WBB route compared to the existing Johns/ Main North Road route. The journey time route is between Johns Road/ Clearwater Avenue intersection and approximately 600m north of Main North Road/Dickeys Road intersection, indicated as alternate route in Figure 3-1. For vehicles on the Johns Road/ Main North Road route there is a saving of around 2 minutes for southbound vehicles in the AM peak with the WBB in place. Outside the AM peak travel times are similar with and without the WBB. Table 3-2 below compares the WBB in 2016 with the existing Johns Road/Main North Road corridor using output from the CAST model. Existing journey times have been obtained from surveys using sensors along the route. Figure 3-1 Indicative Journey Time Routes Table 3-2: Predicted (2016) and Existing Journey Times for the Johns Road/ Main North Road and Western Belfast Corridors Corridor Option Northbound (sec) Southbound (sec) AM peak Johns Road/ Main North Road Existing (2014) Do Min 1 (2016) With WBB 2 (2016) Western Belfast Bypass 180 (140) (240) 3 PM peak Johns Road/ Main North Road Existing (2014) Do Min 1 (2016) With WBB 2 (2016) Western Belfast Bypass 190 (220) (120) 3 Note: 1. The four laning of Johns Road south of the WBB is included in the Do Minimum analysis. 2. The Johns Road/ Main North Road route with the WBB is slightly longer due to negotiating the offramp/ Groynes Drive before rejoining Johns Road 3. ( ) saving compared to Do Min which includes Johns Road Four Laning

10 WBB- Transportation Assessment 7 4 Links and Intersections The WBB affects the Northern Motorway by linking to it and effectively extending the motorway. Key adjoining local roads affected by the WBB include Dickeys Road, Johns Road and Groynes Drive. Overall the proposed access solutions will maintain accessibility to/from these local roads while retaining a high level of service and safety. 4.1 Linking the Bypass to the Northern Motorway At the northern end of the WBB, the bypass effectively becomes an extension of the Christchurch Northern Motorway with connections provided to Main North Road (southbound off-ramp and northbound grade-separated on-ramp), refer Figure 4-1 below. Figure 4-1: Schematic of the Northern Connection Investigations during the scheme assessment stage of the NArt project identified significant capacity constraints in the northbound direction, north of the confluence of the WBB and NArt. To address this, the NArt project proposes widening of the Christchurch Northern Motorway to three lanes in the northbound direction, from Chaneys to north of Tram Road (and including the northbound carriageway of the Waimakariri River Bridge). Assessment has been carried out to determine the performance of the WBB/Christchurch Northern Motorway connection for the interim period, between completion of the WBB and prior to the construction of NArt, refer Figure 4-2 below. For the 2016 No NArt scenario, in the northbound direction, the analysis indicates that the motorway at this location will be within the limit of stable flow with some potential for flow breakdown.

11 WBB- Transportation Assessment 8 At 2026 and with no NArt, the increased traffic demands are predicted to result in unstable flow in the northbound direction with flow breakdown likely. At 2026 and with the Nart the performance remains within the zone of stable flow. NORTH NORTH Prior to construction of the NArt After completion of the NArt Figure 4-2: Schematic of the WBB and NArt connections to the Christchurch Northern Motorway A level of congestion northbound during the PM peak hour is likely to be acceptable for the interim period between construction of the WBB and NArt. However, if the NArt project is delayed significantly from the current programme, then options to mitigate the likelihood of flow breakdown and associated congestion may need to be considered. This could be achieved through 3-laning the section of northbound motorway from the Main North Road On-ramp to the Tram Road off-ramp, inclusive of the Waimakariri Bridge, or through some form of Travel Demand Management (TDM). 4.2 Dickeys Road Dickeys Road is subject to a 100km/h speed limit, changing to 60km/h at the intersection with SH1. The WBB project and associated works (sawmill reconfiguration) will alter the character of Dickeys Road. A new overbridge will be constructed, and the sawmill access will be relocated. A preliminary design safety audit conducted for the project identified the speed limit transition position as a significant safety issue, both currenlty and for post construction of the WBB. This is due to the existing limited sight distance at the crest over the stop bank, as well as the existing narrow river bridge and the proposed overbridge. The independent safety audit recommendation was to relocate the speed limit transition approximately 300m to the west.

12 WBB- Transportation Assessment 9 Speed surveys just east of the bridge recorded an 85th percentile speed of 71km/h in the westbound direction, and 97km/h in the eastbound direction. The procedures set out in The Speed Limits New Zealand publication Guidelines for setting speed limits and procedures for calculating speed limits give a recommended speed limit of 80km/h, based on adjacent land use of Dickeys Road. It is noted that this is based on the development rating (e.g. number of property accesses) and does not fully recognise the geometric deficiencies. It also warns against frequent speed limit changes, in favour of extending adjacent speed limits where appropriate. Relocating the 60km/h limit approximately 300m to the west is considered the most appropriate solution. It matches currently observed speeds in the westbound direction, although will require a significant slowing of traffic in the eastbound direction. More importantly it would recognise existing geometric deficiencies, (stopbank limiting sight distance and narrow river bridge), and future increase in adjacent land use. In the vicinity of the Dickeys Road bridge, Dickeys Road will be widened as part of the project and a sealed verge provided that could be used as a footpath in the future. 4.3 Johns Road/Dickeys Road Intersection As a result of the project, there will be a reduction in traffic flows on sections of Johns Road and Main North Road (currently the SH1 route) through Belfast and at the intersection of Main North Road and Dickeys Road. If constructed, the NArt will link the Christchurch Northern Motorway to QEII Drive and Cranford Street, and will form the primary route into the Christchurch CBD from the north. This project will result in a further reduction in traffic on Main North Road and the intersection of Main North Road and Dickeys Road. The traffic flows at the intersection of Main North Road and Dickeys Road intersection are forecast to significantly reduce by approximately 70% once both the WBB and NArt are complete. This intersection has a poor safety record with 17 crashes in the previous 10 year period, including 2 which resulted in fatalities. A roundabout would mitigate the safety issues at the intersection of Main North Road and Dickeys Road. However due to the high volume of through traffic (both north and southbound), a single lane roundabout will not provide sufficient capacity if the NArt is not constructed. If only the WBB were to be constructed, then a double lane roundabout would address safety and capacity. A signalised intersection and reconfigured priority controlled intersection were also considered and ruled out due to the delays imposed on through traffic on the State Highway and reduced southbound capacity. Given the traffic flows are forecast to reduce as the two projects are completed, there is no driver for this intersection to be upgraded as part of the WBB Project. Careful consideration of intersection performance will be required if the proposed developments in the Belfast Area Plan result in increased traffic volumes at this intersection, particularly traffic turning to and from Old

13 WBB- Transportation Assessment 10 Main North Road (east). This should be considered in any traffic impact assessments carried out for these developments that could occur, particularly off Old Main North Road (east). A standalone project is highly recommended if both the WBB and NArt projects were not to be constructed and proposed Belfast Area Plan development proceeds. 4.4 Main North Road/Johns Road The WBB is predicted to attract a significant volume of traffic away from the existing Main North Road and Johns Road corridors through Belfast. The significant reduction in traffic on the Main North Road corridor will allow for improvements in public transport provision and improved pedestrian and cycling facilities; not within the scope of this project but part of a wider package of transport projects. The reduction of traffic on the corridor will also assist modal change as walking and cycling will become more attractive and faster and more reliable bus services will attract patronage. 4.5 Southern Interchange and Groynes Drive The southern interchange is a grade separated interchange with south facing ramps linking between the bypass and Groynes Drive. A single lane roundabout is proposed at the terminal intersection of the off-ramp with Groynes Drive. The roundabout will also provide access to the Groynes Reserve. Realignment and widening of Groynes Drive is required to provide for the increased traffic volumes and overpass configuration of the interchange. Figure 4-3: Schematic of the Southern Connection The Groynes Drive/Johns Road Intersection will be upgraded to tie-into the widened cross-section of Groynes Drive. The intersection configuration is to remain as a priority controlled T-

14 WBB- Transportation Assessment 11 intersection with a right turn bay retained on Johns Road for vehicles accessing the Groynes Reserve and dog park. Refuges will be provided to assist pedestrians and cyclists crossing Johns Road and Groynes Drive; connecting the Groynes Reserve and Groynes Park Ltd subdivision (Eminence) to the Northwood Boulevard pedestrian link and the cycle connections along Johns Road to the Clearwater Avenue roundabout. Groynes Drive will be widened and upgraded to include a 2.5 m wide shared pedestrian/cycleway path along the eastern edge of Groynes Drive and a footpath along the majority of the western edge. There will also be 1.5m wide shoulders to allow for on-road cyclists and Groynes Drive will retain access to The Groynes via the proposed Groynes Drive overpass. Traffic volumes on Johns Road at the Johns Road/Groynes Drive intersection will decrease from 28,500 vpd existing to 6,200 vpd in 2016 with the WBB which will significantly reduce the traffic delays currently experienced in exiting Groynes Drive. It is understood that in the long term planning for the park the main entrance to The Groynes is being relocated by CCC to off Clearwater Ave so only those using the Dog Park will access The Groynes from Groynes Drive. In summary, the WBB reduces traffic on Johns Road at the Groynes Drive intersection which will reduce delays for vehicles exiting the Groynes Park Ltd subdivision and The Groynes. The upgraded Groynes Drive will provide enhanced pedestrian and cycling facilities through a shared pedestrian/cycleway path, sealed shoulders and pedestrian refuges on Groynes Drive and Johns Road. A flush median and right turn bay will also provide safe turning facilities into the subdivision, Rosebank Estate and Chardonnay Motels. 4.6 Walking and Cycling Pedestrian and cycle facilities for the Western Belfast Bypass project are proposed to include: Off-road shared pedestrian and cycle path linking Clearwater Avenue with a new service road to properties south of Johns Road in the vicinity of the on-ramp (refer Figure 4-3), Cycle and pedestrian facilities along Groynes Drive (shared footpath and on-road cycle shoulders); Pedestrian path at the toe-of the southern interchange embankment linking the Waimairi walkway to Groynes Drive (to provide continuation of the Waimairi Walkway which is severed by the WBB). The path will be designed as a pedestrian path, but will be future proofed with sufficient width provided adjacent to the path to enable possible future widening to cater for cyclists No pedestrian or cyclist provision is provided along the WBB between the southern and northern interchanges which is to be designated as motorway.

15 WBB- Transportation Assessment 12 5 Safety The Scheme Assessment report investigated the reported crashes on SH1 between Dickeys Road to the intersection of Johns Road and Willowcreek Lane (2.2 km west of Main North Road) The dominant type of injury crashes are crossing/ turning and rear-end/ obstruction, reflecting the high proportion of crashes within the study area that occurred at intersections. The bypass will have an overall benefit in reducing the rate of crashes throughout the network. These benefits accrue from a reduction in traffic volume through the Main North Road Johns Road corridor and a reduction in crashes from vehicle to vehicle and vehicle-pedestrian/cycle interactions at intersections. The vehicles that shift to the WBB have a safer route due to the motorway standard design and the reduction in conflicts due to no access along the WBB. 6 Traffic Management during Construction Construction of the WBB will be advantaged by the almost entire length of the project being greenfields and completely separated from any other existing road network. This will ensure that a large portion of the project can be constructed without disruption to traffic. However, construction of both the Northern and Southern interchanges will require construction machinery working on and around existing roads where there is the potential for interaction with local traffic. In relation to property accesses that may be affected by the construction works, all practical steps will be taken to reduce the impact of construction activities or temporary traffic management measures on property access (vehicular and pedestrian), existing on-site parking or manoeuvring areas. Under exceptional circumstances where construction methodology or staging prevents continuous vehicle and pedestrian access to property, communications with the affected parties will be undertaken. These communications may include (but is not limited to) the following: information about the works duration of the works likely impact on access and alternative access arrangements, where applicable date of the works contact details for the Contractor. All reasonable measures to reduce or mitigate the impacts of such activities will be put in place, which may include (but is not limited to), the following: temporary access ways using metal plates or other methods construction methodologies that allow access during critical time periods provision of alternative parking or manoeuvring areas. It has been assumed that during construction all of the current roads will remain open and accessible; however traffic management will be required with some reduction in highway capacity for short periods. The tie-ins to the Northern Motorway at the northern end of the project and to Johns Road (northern end of the Groynes to Sawyers Arms 4-Laning) will be the most complicated to construct

16 WBB- Transportation Assessment 13 whilst retaining existing connectivity and some localised temporary routes/diversions are likely to be required. The management of construction traffic is typically controlled through a Temporary Traffic Management Plan prepared in accordance with the NZTA Code of Practice for Temporary Traffic Management. The application of effective Temporary Traffic Management (TTM) planning and implementation is critical to the success of the project, as TTM can have a significant impact upon the operation of the overall road network. With careful assessment of the variety of issues and identification of effective mitigation, the impacts can be significantly reduced. Temporary traffic management (TTM) shall be in accordance with: NZTA s Code of Practice for Temporary Traffic Management (COPTTM) for work on the State Highway Christchurch City Council s requirements where local roads are involved. To mitigate any actual or potential adverse traffic effects associated with the construction of the proposed WBB project, a Temporary Traffic Management during Construction Management Plan (TTMCMP) will be prepared and forms part of the proposed conditions on the designation. Prior to any site works commencing, the Contractor will be required to prepare and submit the Construction Traffic Management Plan (TMP) to Christchurch Transport Operations Centre (CTOC) and NZ Transport Agency s network representatives for approval.