New geomembrane for cracked reservoir

Replacing a geomembrane layer is part of a $163 million repair and expansion job for Tampa Bay Water’s (TBW) cracked reservoir.

The Kiewit Infrastructure Group’s proposal aims to repair and expand the utility’s six-year-old, 15.5-billion-gallon facility.

Kiewit estimates repairs at about $121 million. The contractor’s plan will remove and reclaim the reservoir’s existing flat-plate soil cement and soil wedge, remove and replace the PVC geomembrane layer, and add embankment fill, a drainage system, and stair-step soil cement around the entire interior face.

The contractor’s proposal also calls for expanding the existing facility by an additional three billion gallons, at an estimated cost of nearly $42 million.

In late 2006, a year after the $140-million facility first opened, TBW discovered cracking along about 40% of the reservoir’s interior lining. An investigation concluded that the cracks were caused by water becoming trapped in the soil wedge.

TBW officials said construction could start by September 2012 and last 24–30 months.

Source: ENR.com