THE SPIT BRIDGE The NSW Government on Friday 18 August 2006 announced a $60m plan to add two more drawbridge lanes to the Spit Bridge. This is a very bad idea. The sole benefit will come in the form of modest time savings for counter-peak traffic. No benefit whatever will be gained by Northern Beaches residents who presently commute daily in the direction of the city. The plan offers no incentive for users of public transport and promises even greater congestion on Military Road and other thoroughfares in Mosman, Cremorne and Neutral Bay. A much more realistic plan developed by Michael Darby and (then) Liberal Councillor David Dickman in 2002 has long been displayed at the website http://michaeldarby.net/tunnel.pdf. Note the alternate route displayed in white on page 4. This involves a single lane cable-stay high level bridge on the eastern side of the Spit Bridge and an elevated roadway across The Spit. The advantage is greatly reduced gradients and the disadvantages are greater length and increased visual impact. Let private enterprise invest in a switchable tunnel of one or two lanes from Manly Vale to Cammeray, which will bring enduring benefits to the residents of the Northern Beaches. Page 1 of 7
Switchable Public Transport (SPT) Lane The cost-effective, practical method of alleviating traffic congestion on the Spit Bridge and on Military Road is a Switchable Public Transport (SPT) lane, mostly underground, from Manly Vale to Cammeray. The SPT lane will give priority to buses and taxis, with remaining capacity for E-tag trucks and E-tag public light buses; plus private cars, for which fees are automatically varied to keep average velocity at not less than 40 km/hr. The extra lane would operate city bound from midnight to midday Monday to Friday, and northbound from midday to midnight Monday to Friday. On weekends the extra lane would continue northbound from midnight Friday to midday Saturday, then operate city-bound midday Saturday to midnight Saturday, then northbound midnight Saturday to midday Sunday. The city-bound direction continues from midday Sunday right through to midday Monday. Page 2 of 7 THIS PRESENTATION IS GROWING. PLEASE RETURN SOON FOR MORE INFORMATION The tunnel can be constructed in single-lane or dual-lane form The case for a single lane tunnel A typical single lane bored road tunnel requires excavation of around 91,000 cubic metres per kilometre, whereas a typical two-lane bored road tunnel requires excavation of around 314,000 cubic metres per kilometre more than three times as much. The cost saving with a single-lane tunnel permits investment in a high-tech stranded vehicle recovery system. CLICK HERE FOR MORE ON THE SPT
Benefits of the SPT lane will include: 1. Significant shortening of peak hour travel times for buses and taxis, with increased productivity of both categories of vehicle. 2. Reduction of congestion at Seaforth Roundabout and Sydney Rd Manly Rd intersection. 3. An end to the expensive and labour-intensive lane-swapping of the Spit Bridge. Note that the Spit Bridge is presently a significant bottleneck only for counter-peak traffic, and there is no justification whatever for the stupid and expensive plan to build an extra two-lane drawbridge. 4. Significant reduction of bus and truck traffic on Military Road through Mosman, Cremorne and Neutral Bay and greater effectiveness of shorthaul buses. 5. For SPT lane users, the distance from Manly Vale to the City will be shortened by nearly a kilometre. The distance from the freeway at Cammeray to Manly Vale will be travelled by a bus in less than twelve minutes. Page 3 of 7 The Future The SPT Lane will not detract from possible future developments, which could be a second single-lane or dual-lane tunnel, a multi-lane long tunnel, a railway, a rubber-tyred mass transit system, or perhaps even a magnetic levitation system. The SPT Lane provides a cost effective means of accelerating public transport, reducing the numbers of trucks and buses on Military Road, and contributing very positively to safety. Moreover, the SPT Lane is intended to be self funding. There is every reason for the NSW Government to invite expressions of interest for putting the concept into practice.
SWITCHABLE PUBLIC TRANSPORT (SPT) LANE To alleviate congestion on Military Road and on the Spit Bridge. On Weekdays the lane travels from north east to south west from midnight to midday, and from south west to north east midday to midnight. The flow times are reversed on weekends and public holidays. Adelaide uses a switchable highway for commuters Page 4 of 7 Proposed Tunnel Castlecrag Northbridge Middle Harbour Cremorne North Balgowlah Mosman Balmoral Beach Balgowlah Heights The cost effectiveness of a single switchable lane is very significant. The proposed SPT tunnel will not detract from other contributions to improving the lives of Many-Warringah- Pittwater commuters, which include Brian Kent s St Leonards to Brookvale railway plan and Cr Jim Reid s proposal for a rubbertyred mass transit system. For more detail see following pages RETURN TO SPT PAGE 1
By reducing peak hour bus time Manly Vale to St Leonards Park from 30 minutes to 12 minutes, the tunnel will allow more daily journeys with the same number of buses, and demand for bus travel will increase because of the time saving. Trucks and taxis will also benefit. Private motorists will take up the remaining flow, using E-tag. Seaforth Manly Vale N See next page Water depth exceeds 50 metres, and this will be reflected in the tunnel gradient from Seaforth Middle Harbour Proposed Tunnel Page 5 of 7 Spit Bridge Up to three north-east portals The Myrtle Street Bridge requires modification with twin arches replacing the centre pillar, to allow the median strip of the Burnt Bridge Creek Deviation to operate as the switchable lane feeding traffic from Manly Vale to the tunnel midnight to midday, and accepting northbound vehicular output from the tunnel midday to midnight.
Ventilation is by towers containing natural gas burners which burn some pollutants while heating the column of air so that it rises to a safe altitude before dispersing. Proposed Tunnel See previous page Planned tunnel traffic velocity is 40kph (min), maintained by automatic E-tag price variations displayed on approaches to the portals and narrow cast on FM radio. Northbridge Golf Course Middle Harbour N Enquiries: Phone Michael Darby 02 9972 9316 Crows Nest Cammeray Golf Course Page 6 of 7 Two or more portals at south-west end of tunnel
Australia s First One-Way Freeway Kindly contributed by Hilton Lenard The Southern Expressway, built in two stages between 1997 and 2001 is the world's first fully reversible one-way freeway /expressway. It was built parallel to Main South Road to provide a third major arterial road to the southern regions of Adelaide. While that sounds innovative, it was initially built that way to obviously cut costs as building freeways is something of a novelty to the South Australian government. Nevertheless, upon opening day in late 1997 it was touted to be a failure but has in hindsight been a complete success as it has spread and diverted the once heavily congested Main South Road's traffic (for now, anyway). While Stage 1 was a breath of fresh air for driving into the southern suburbs, it was Stage 2 that has proven the greatest asset by bypassing Morphett Vale and Reynella which was (and still is) an annoying and painstaking slow journey to negotiate. The only sour point is that the absence of significant future provisions for either road widening or if one day the road really *does* need to be flowing in both directions. State: South Australia Start: Bedford Park - Main South Road Interchanges: Marion Road (Sturt), Main South Road/Panalatinga Road (Reynella), Sherriffs Road (Lonsdale), Beach Road (Noarlunga Centre) Finish: Old Noarlunga - Main South Road Length: 21km Direction Times: Northbound (Mon-Fri: 2:30am-1:30pm, Sat-Sun- Public Holidays: 2:30pm-1:30am), Southbound (Mon-Fri: 2:30pm- 1:30am, Sat-Sun-Public Holidays: 2:30am-1:30pm). No traffic enters 1:30pm-2:30pm and 1:30am-2:30am each day. Road Standard: All bitumen. Road Quality: Excellent. Triple carriageway from Bedford Park to Reynella. Dual carriageway from Reynella to Old Noarlunga. Freeway quality for the entire length with emergency stopping lanes. Depending on the direction, watch for the unusual right lane on and off-ramps as it can cause some surprise when the fast lane suddenly has to merge with entering traffic. Speed Limit (outside start and end points): 100km/hr - 80km/hr on the Tapleys Hill descent. Click here for photos Still, in the meantime its a novelty and tourist attraction for those who live interstate - so visit South Australia and see the one-way freeway! Page 7 of 7