More work is planned at Lee Lake to repair a leaky pipe deep beneath the water’s surface, Director of Engineering Micah Siemers said this week.
The leak is to blame for declining water levels at the City-owned fishing lake, located on Adams Boulevard east of Silver Lake Road.
“The leak is in a concrete pipe that was intended to allow for the lake to be drained, if it ever needed to be, and for draining overflow from the lake,” Siemers said. “The pipe is very deep below the surface and has penetrated that bank.”
Triangle Construction, the company that originally constructed the lake, was contacted last week to review options. Temporary measures were taken to slow the leak and ideas on how to permanently fix the pipe were discussed, Siemers said.
“They installed inflatable sewer plugs in the pipes at multiple locations in hopes of stopping the leak,” he said. “Unfortunately, this has not worked, though it has slowed the leak substantially.”
Siemers said the problem is that the water has made its way to the gravel pipe bedding and is now bypassing the pipe altogether and still exiting at the creek bank.
“It’s coming out under the concrete apron/slopewall on the creek side,” he said.
Siemers said the plan now is to import shale or tight clay and construct a “peninsula” from the bank, around the concrete structure.
“Hopefully this will stop the leak, at least temporarily,” he said. “Once they get that installed they will excavate the pipe from the structure to a point about 20 feet beyond the top of slope and replace the concrete pipe with PVC pipe more typically used for waterlines.”
Siemers said a pipe sleeve will be installed where the concrete pipe has been cut and the trench will be backfilled and compacted with the clay or shale material.
“We will come towards the lake along the new plastic pipe 10 feet or so and install another concrete water stop larger than what was originally installed to hopefully block any water that might still infiltrate the trench over time,” he said. “Like any earthen dam there will be some degree of infiltration and seepage, but hopefully this will eliminate the measurable water loss we have happening now.”
The project is expected to cost between $15,000 and $20,000.