Additional safety improvements are being included as part of the new passing lane nearing completion on State Highway 1 (SH1) between Otaki and Waikanae.
Additional safety improvements are being included as part of the new passing lane nearing completion on State Highway 1 (SH1) between Otaki and Waikanae.
The NZ Transport Agency (NZTA) Wellington Acting State Highways Manager Mark Owen says the project includes safety improvements such as the removal of a deep roadside ditch and improved manhole design. However, extra safety improvements including a re-designed stormwater culvert and changes to the central median strip are being added to the project’s programme.
“The new 2km southbound passing lane at Peka Peka is considered an ideal location to trial a new system of providing greater separation between opposing traffic flows by creating a visual barrier rather than installing a physical median barrier,” says Mr Owen.
The trial is to investigate improvements to highway safety compared with installing a median barrier system. A 1.5m wide median strip is being painted between the north and southbound lanes and reflective, flexible plastic posts are being installed at 5m spacings.
Mr Owen says that the new passing lane, which is expected to be finshed by the end of the month, completes the NZTA’s passing lane strategy for this area.
“There was only one southbound passing lane between Otaki and Waikanae, approximately 5km south of Otaki, so this second opportunity to overtake slower road users is expected to improve traffic flow, reduce driver frustration and therefore improve overall safety on the region's transport backbone,” he says.
Mr Owen adds that because the necessary earthworks encroached onto former swamp land on one side of the carriageway, the site was closed last winter to allow this ground to settle before the new passing lane could be constructed.
“We really appreciate the patience of locals and motorists during the past 18 months.
NZTA is committed to reducing the road toll by improving the safety of New Zealand roads. Ongoing safety reviews by NZTA have identified that SH1 from Wellington to Levin has a high potential for head-on crashes due to the high volumes of traffic. The installation of median barriers has proven to be successful in reducing head-on crashes, but NZTA would also like to investigate the merits of alternative median treatments.
The new Peka Peka passing lane is considered an ideal location to trial* a 1.5m wide painted central median strip with white flexible plastic posts installed at 5m spacings. This will provide greater separation between opposing traffic flows and creates a visual barrier similar to that in the photograph below and as shown in Diagram A.
Diagram A – revised passing lane layout, median strip and road markings.
Please note that the trial will maintain access to all properties by leaving suitable gaps for vehicles to enter and exit all driveways that have direct access to this section of SH1. The shoulder on the eastern (southbound) side of the project will enable southbound vehicles to pull over to the left, clear of the through lanes, before turning right into these properties should this manoeuvre be considered appropriate by motorists in the interest of safety and as shown in Diagram B.
Diagram B – provision for right turn across SH1
During the passing lane project consultation process, a number of residents queried whether a future wire rope barrier would be installed. This trial is completely separate to any wire rope barrier proposal – the flexible posts are not suitable for a wire rope barrier installation so would need replacing were a barrier to be installed.
*The NZTA advises that these sorts of trials normally extend for between two to five years during which time the Agency’s safety engineers will monitor the effectiveness of this new median treatment in reducing head-on crashes and cross-line incidents via the NZTA Crash Analysis System.