KEY POINTS:
Can you tell me how many offramps there are and where they are on the new State Highway 20 extension, starting at Hillsborough Rd until it reaches Maioro St/New Windsor Rd?
Also, what provision is being made for traffic dispersion when the highway ends in the heart of suburban Mt Roskill?
Terry Henderson, Auckland.
Transit, which kindly supplied the graphic, tells me that there will be 10 onramps and offramps along the Mt Roskill extension. Hillsborough Rd and Dominion Rd will each have four on and offramps, and Queenstown Rd will keep its on and offramp.
A new roundabout is being built at Maioro St where this part of the motorway will end and traffic will disperse on to local roads. Construction is also taking place at the intersection of Sandringham and Stoddard Rds, where traffic lights have been installed, and at the intersection of Maioro and Richardson Rd.
When it's all finished Maioro will have two lanes in each direction.
Auckland City Council is doing its bit too, upgrading Tiverton and Wolverton Sts in New Windsor to link with SH20. Part of Tiverton St has been widened and improved, and stage two of the project will widen Wolverton St and the rest of Tiverton St to four lanes.
Roundabouts at the intersections of Blockhouse Bay Rd and Tiverton and at Whitney St and Tiverton will be replaced with traffic signals.
And when the Waterview extension begins, SH20 will be extended from the Maioro St interchange to connect with SH16 at Waterview.
I live near the intersection of Hillsborough and Carr Rds. Since the closure of Hugh Watt Drive from Hillsborough to Melrose Rd because of work on the SH20 extension, there has been an increase in the volume of traffic travelling through this intersection.
I know that Hillsborough Rd will remain a main arterial route, but I wondered roughly what percentage decrease in traffic volumes through Hillsborough and Carr Rds Transit expects when the motorway extension is complete.
Andrew Scott, Hillsborough.
When the new part of SH20 is open next year, traffic now using Carr Rd will have the choice of exiting at the new Dominion Rd interchange or the Hillsborough Rd interchange. It is therefore expected that the amount of traffic will decrease slightly.
But (there's always one), Carr Rd will always have more traffic because it services schools and businesses. So we shouldn't expect any miraculous drop in traffic volumes.
Can you please explain the difference between a motorway and an expressway?
Jack Norton, North Shore.
I sure can. Pedestrians or Cyclists are not allowed to use a motorway , and drivers can get on to a motorway only at onramps and interchanges. An expressway looks much the same as a motorway, but pedestrians and cyclists can use it, and there is access for people whose properties lead on to it.
