Unexpected water delays Court St. bridge project

LACONIA — The replacement of the bridge on Court Street over Durkee Brook will be delayed up to six months because of unexpected complications in installing water and sewer lines across the brook, according to the city.

The replacement of the 12-foot span had been scheduled to take place in April, but workers encountered extensive water below the bottom of the brook. As a result new engineering plans need to be drawn up and new permits obtained from the state environmental officials, Public Works Director Wes Anderson said.

The original plan had been to install a new water line under the brook. However, when workers dug down close to the depth where the line would be installed they ran into an underground layer of water that is likely being fed either from water in the brook or Lake Winnisquam, Anderson said. Furthermore, tests show that that underground water is slightly contaminated, he added.

As a result, most of the water line crossing the brook will now have to run alongside the bridge rather than underground. The plans to replace the sewer line completely have had to be shelved. Instead, the line will be upgraded by inserting a liner into the existing line which will strengthen it.

The pool of underground water is “slightly contaminated,” which Anderson said means that although it is not a danger to people it cannot be discharged as is into the brook or lake. Instead it must be taken off site to be treated.

Anderson said the contamination could be coming from material that has been in the surrounding soil for many years, perhaps dating back to the early 1900s. He said the evidence from test pits has ruled out that the contamination is related to a gas leak several years ago at the Budget Gas filling station which abutted the brook.

Anderson said the city hopes to submit the revised plans to the state Department of Environmental Services by mid-March.

Work on the redesigned water and sewer lines as well as the storm drains will take place during the spring and summer. The bridge will be kept open to two-way traffic during the height of the summer tourist season, Anderson stressed. However traffic will be restricted briefly while construction equipment is repositioned.

The hope now is to replace the bridge itself between Labor Day and Columbus Day, or after Columbus Day, said Anderson, noting the earlier time frame would be preferable because it would give crews more time to work on the approaches to the bridge while the weather is warmer.

“We try not to plan any work after Nov. 15,” he said.

Court Street will be closed to through traffic during that time while prefabricated bridge components are installed.