Two more bridges have joined the list of closed bridges in Southland as their continued use would pose a "serious threat to public safety".
The Scott Rd bridge in Hokonui and the Thomsons Crossing Rd West bridge, near Winton, were closed by Southland District Council on Wednesday.
Both wooden bridges failed their annual structural inspections and will be closed to all traffic. Alternative routes are available, and add less than 10 minutes to the journey.
Public meetings were held earlier in the year for three other bridges deemed unsafe for vehicle use - the Mataura Island-Titiroa bridge, Channel Rd bridge and Evans Rd bridge.
An SDC spokesman said no bridges that provided general public access had been closed permanently and the three bridges closed earlier in the year were likely to be reopened to light traffic in September.
"All three bridges are having gantry structures installed, which will limit the size and therefore the weight of the vehicles able to drive over them."
There were more than 850 bridges in Southland, and given the small rating base, they provided a challenge for the council, he said.
"The majority of bridges were all built roughly around the same time out of the same material - timber. Subsequently, they are all starting to reach the end of their useful lives."
About 450 had been assessed in the 2018-19 season and there were still about 330 bridges - excluding posted bridges - programmed for inspection during the 2019-20 season.
Many of the bridges had been "overloaded", including by users not following weight restrictions which exacerbated deterioration.
The SDC had two contracts out to tender and up to 19 bridges could be replaced, he said.
Also tenders had been awarded for the replacement of two bridges during the 2019-20 construction season.
Major component works had been carried out on the Mataura Island-Titiroa bridge, Channel Rd bridge and Evans Rd bridge and another half dozen were programmed, he said.
For the 2018-21 period about $3million had been allocated for bridge upgrades and renewals. An additional $1.5million had been approved by the council to gain available NZ Transport Agency funding of the same amount.
"This brings the total budget over the 2018-21 period assigned to bridge upgrades and renewal to around $6million."
While the most vulnerable bridges were monitored regularly, all posted bridges were inspected annually to establish if they had "sufficient structural integrity" to remain open for public use - it was not planned to replace or repair the two most recently closed at present.
"It is intended to canvass community priorities and associated funding obligations through the 2021 long-term plan consultation process. This consultation process is due to begin in the early stages of 2020."
