By CLAIRE LOWE

Staff Writer

HAMILTON TOWNSHIP – County officials lifted all restrictions on Lake Lenape as of Monday, June 13 when normal water levels returned.

Lake Lenape was closed June 6-10 to boaters after water levels had lowered significantly. But, recent problems on Lake Lenape concern more than just boaters.

 

In their attempt to repair a leaky valve under Lake Lenape, Atlantic County and Hamilton Township, which own equal parts of the dam, have run into a few issues.

The latest is a partially open valve under the Lake Lenape dam which may have contributed to the lake's low water levels, Hamilton Township Administrator Michael Jacobs said Tuesday, June 7.

Jacobs said he found out that morning the contractor who recently began a project to repair the dam did not have the valves that run under the dam fully closed. The valves control the water level in the lake.

Jacobs said after the valves were closed off between Monday night and Tuesday, June 7, using a piece of sheet metal placed in front of the valve, the lake began to hold more water.

"This morning the lake was already up two inches," Jacobs said that afternoon.

In the township's agreement with the county for the dam, the township is responsible for maintaining the level of the water going over the dam. A recent contract for the repair of the dam has shifted that responsibility to the contractor, Agate Construction.

"When this contract was awarded, that immediately became the responsibility of the contractor," Jacobs said.

Over the years, the valves that run under the spillway of the Lake Lenape Dam, controlling the flow of water out of the lake, have deteriorated.

"Those gate valves have deteriorated over many, many years," Jacobs said. "They don't close all the way and with some of them, the water is actually going around the big pipe that's under there. We can't go out there and just start spinning the handle and crank the valves shut and stop all water from going under the valve."

In order to remediate the problem, Hamilton Township and Atlantic County hired Agate Construction to do what Jacobs called a "design build bid spec" where the contractor hires its own engineer to design the project.

Jacobs said the plan was to build a cofferdam using sheets of steel driven into the lake bed forming a secondary dam and creating a dry space between the dam and the cofferdam in which to make the repairs.

But the repair didn't go according to plan when lake-side residents were put on alert March 1 by local police that evacuation may be necessary due to possible flooding caused by the cofferdam leaning inward. The problem was repaired and no evacuation was needed.

Jacobs said the leaning was caused by the pressure of the water on the sheet pilings created by the construction process.

He said to install the cofferdam, the contractor works his way across installing one sheet at a time.

"The smaller the opening gets, the faster the waters come through the little space left," he said. "That dug a hole under the cofferdam and it leaned in."

To remedy the problem, Jacobs said, Agate plugged up the area with fill and drove the other sheets below water level so they wouldn't lean.

Now the contractor cannot begin working on the dam again until November when the lake is allowed to be lowered. Jacobs said he is not sure if all the work done to this point was for nothing or if the cofferdam can be repaired.

"If they can just lower the water and they can fix that corner, then maybe that's not the case," he said.

County engineer Joseph D’Abundo was not available for comment in time for publication.