Stonington -- The town is working toward repairing two bridges, one which has been closed since 2010 and the other which the state says is in serious condition and provides a vital link with Westerly.

Stonington and Groton are working together to finally reopen the North Stonington Road bridge which was damaged in a flood while town officials plan to meet Monday night with the Westerly Town Council about working together to repair the Stillman Avenue bridge.

Town Engineer Scott Deledda told the Board of Selectmen last week that the North Stonington Road bridge cannot be repaired and has to be replaced at an estimated cost of $1.2 million. The state will pay for half of the cost.

The selectmen also approved the use of $90,000 left over from previous design work on a repair project to begin the preliminary design for the replacement and permitting. Each town’s $300,000 share of the cost will be reduced by its $45,000 share of the escrow.

Deledda said the preliminary design work will keep the project moving forward and give the town the information it needs to seek funding in the capital improvement budget.

When the original contractor for the project began work on the repairs in 2011, it discovered the design was flawed and that a new deck likely would be needed because the concrete had deteriorated. Work ceased as that work had not been part of the design. Since then, it has been determined the abutments also needs to be replaced.

The towns have since recouped much of the $100,000 spent on hiring the engineering firm that designed the initial repair project.

With the bridge closed to vehicle and pedestrian traffic, it cuts off one of the access roads to Old Mystic Fire Department Station No. 1.

Fire Chief Ken Richards has said that his trucks must use a detour that poses a safety hazard to his firefighters and other motorists.

State transportation officials have informed the town that an inspection has revealed the Stillman Avenue bridge spanning the Pawcatuck River is in serious condition and needs to be rehabilitated or replaced.

The well-traveled bridge is one of three that span the Pawcatuck River between Stonington and Westerly.

According to the summary of the inspection, the steel girders have severe rusting and other steel components have holes or have rusted away. Due to the “serious and declining condition” of the span, the state is now determining the load the bridge can handle and will report those results to the town.

The report also warns that during a 10-year river flow event, which has a 10 percent chance of occurring in a given year, it is possible the soil supporting the bridge will be eroded, undermining it and making it unsafe.

The state has recommended the towns of Stonington and Westerly, which are jointly responsible for the bridge, should monitor the span during floods and “take whatever action is necessary to ensure the safety of the public up to and including the closure of the structure.”

First Selectman Rob Simmons said repairing the bridge is even more complex than normal because it involves two towns and two states.

Selectman Mike Spellman suggested the town also examine the White Rock bridge and Pawcatuck River bridge to determine if they can handle the additional traffic that would be generated if the Stillman Avenue bridge is closed.

Selectwoman Kate Rotella proposed that Simmons assign a team to provide selectman with a bimonthly report on the status of the bridge projects.

j.wojtas@theday.com