Case Study - Environmental

Client
Dogwood Lakes Community, Holmes County, FL

Project
Rehabilitation of Stormwater Overflow Manhole (Located in Middle of Lake in Golf Course Community)

Location
Dogwood Lakes, Holmes County, Florida

Description
Tens of thousands of gallons of water, per day was infiltrating into the structure primarily from the bottom of the lake. The infiltrating water was boiling in through the bottom and were being discharged into a ravine at the end of the storm drain pipe, steadily reducing the level of the lake.

Solution
The Poly-Triplex Liner System was chosen to structurally line the entire manhole structure. The liner was made considerable thicker in the bottom and floor section of the structure. Once installed, the liner is bonded to the host structure and has stopped all infiltration of lake water coming from that area. The company provided the City of Bonifay with a 10-year non-prorated warranty to stop the infiltration.

Benefit
There was a huge cost savings in being able to line the structure. The problem was resolved within two weeks at a construction cost of less than $20,000, rather than the anticipated cost of approximately $300,000, or more. one month the lake was already within one foot of being at the maximum lake level. Docks are back to a useful position for boating and lake recreation and the people of Holmes County and residents of Dogwood Lakes are happy to have their lake back to normal, finally.

Photos
Environmental
Upper Left: Lake lowered approximately 5 feet lower than normal.
Upper Right: Lake water boiling into the structure.

Environmental
Upper Left: Lake water being discharged through overflow pipe.
Upper Right: Overflow pipe structurally lined & all infiltration stopped.

Comments
Excavation for replacement of the structures was near impossible and it was expected that a repair cost would be several hundred thousands of dollars and would include either building a coffer dam or draining the lake at least another 12 ft. This method would also have required closing of the road. The road was one of only two roads coming into the neighborhood – and disruption of traffic and utilities, for an extended length of time, would have been a serious inconvenience for visitors and residents.