Cost, land rule out roundabout on Kamo bypass | Northland News | Local News in Northland

A roundabout capable of handling more than 30,000 vehicle movements daily would have been too big for the new Kamo bypass intersection, not to mention too expensive, the New Zealand Transport Agency says.

Motorists using the new bypass intersection at Kamo Rd have been frequently frustrated over the past month by long lines of slow traffic which have meant some people waiting more than 20 minutes to cross the intersection.

The NZTA last week said traffic sensors had not yet been put in the road and the intersection lights had been using old data to control traffic flow.

The problems created by the faulty lights prompted many drivers to ask why a roundabout was not installed at the intersection. The NZTA told the Northern Advocate roundabouts required more land than intersections controlled by lights.

"Building a new highway in a city environment has a number of challenges and the NZTA had to balance the needs of drivers with the those of the community living beside the Kamo Bypass Stage 2 project," a spokesman said.

"A roundabout requires more land than a conventional intersection controlled by traffic signals. In order to reduce the number of properties required for the bypass and to minimise disruption to our neighbours living near the project, the NZ Transport Agency determined that traffic signals were the best solution.

"A roundabout of the size needed to cope with traffic demand would have cost an additional $2.7 million in construction costs, without even factoring in the purchase of additional land."

He said a small roundabout would not be viable to meet the demands of the 30,000 vehicles that used the intersection today as well as to cope with future demands.

The NZTA expects to finish work on the Kamo bypass by the end of the month.

Traffic sensors at the bypass intersection will go in once resurfacing is done, their data impacting on the lights' timing.

The NZTA also acknowledged it was still responsible for the "old SH1" as far as the roundabout at the bottom of the Kamo hill. It had begun the process of revoking the state highway status and would hand responsibility to the district council as soon possible.

US research found roundabouts were safer than intersections with signals, reduced frequency and severity of crashes and reduced delays. (Source: Nevada Department of Transport)