Mohaka Bridge may get 'Stop-Go' signs

Northbound holiday traffic on the Mohaka Bridge between Napier and Taupo yesterday. Photo / Warren Buckland

Three-minute traffic light stops on the Napier-Taupo Highway's Mohaka Bridge are expected to be replaced by manned patrols during the remaining holiday peaks because of some concerns over the impact of the short delays on the patience of some motorists.

The request for staff with "Stop-Go" signs was made to highways consultants Opus yesterday by police as traffic backed-up several hundred metres during the alternating stops, controlling traffic reduced to one lane during several weeks of bridge maintenance and restrengthening.

The temporary lights, along with a 30km/h speed limit on the bridge, and a 60-tonne maximum weight for trucks, which are also required to travel no closer than 40m apart, have been in use for six weeks.

Hawke's Bay Police road policing sergeant Kevin Stewart said police have asked for manned patrols during peak daytime periods, the busiest expected to be as people head home on Sunday - either to or from Hawke's Bay.

Police urge motorists to plan their trips home allowing for longer travel times in heavy traffic and rest stops.

Yesterday afternoon, when a Hawke's Bay Today reporter and photographer visited the Mohaka Bridge 60km northwest of Napier and just east of Te Haroto, traffic varied on the highway (officially known as State Highway 5 and also known as the Thermal Explorer Highway), but no more than 30 vehicles queued in any of the three-minute stops during an observation of about 45 minutes.

Mr Stewart said that wouldn't seem much to Aucklanders, and the short break could benefit some motorists, but the request had still been made to have staff at the bridge at peak times, while police highway patrols will monitor the area.

The work is the latest of several restrengthening tasks carried out over the last four years on the 50m-high, 215m-long steel bridge, built in 1962. Seismic restrengthening was done in 2009 and early in 2012 contractors carried out a seven-week project to meet the demands of increased heavy transport usage "for many years to come," a report said.

The structure is a vital link to Hawke's Bay, with no viable detour and authorities have strived to ensure the bridge remains open during maintenance. One of its longest closures was in October 1995, after the worst crash in Bay history claimed eight lives, when a housebus crashed through the western rail and plunged almost 50m to the river bed below.