Safety issues have led to one of Hawke's Bay's oldest State Highway 2 bridges reduced to single-lane traffic.

The situation on the Tahaenui Bridge, near Nuhaka and 24km east of Wairoa, follows the completion of repairs after a serious crash on the bridge in April.

With the NZ Transport Agency confirming it has been done for safety reasons, it becomes the only one-way bridge on the 334km through-Hawke's Bay stretch of SH2 between Dannevirke and Gisborne.

No decisions have been made on the future of the bridge, which was built in 1930, but investigation includes the one-way bridge trial, said NZTA regional transport systems manager Wayne Oldfield.


"It is still in fair condition and continues to be monitored," he said.

"Over the last five to six years the bridge has undergone substantial repair and maintenance works including deck joints, bearing, concrete repairs, scour protection and replacements of damaged guard railing."

There have been 14 crashes in close proximity to the bridge in the past 10 years, and safety issues have arisen not only because of the narrowness of the lanes but also because of debris regularly left behind by the varying scrapes marking its history.

The bridge is currently under management with a 50km/h speed limit and a requirement for northbound traffic to give way to traffic heading towards Wairoa and Hawke's Bay.