Potable water tank leaking expansion joints sealed
Client: Albertville (Ala.) Municipal Utilities Board
PROBLEM: The operator of the Albertville, Ala., water treatment facility contacted an Atlanta-based concrete repair contractor regarding leaks in a 50-year-old potable water tank (in late 2011). The structure was losing water faster than the plant could treat it. The water was leaking from vertical expansion joints in the exterior wall and expansion joints in the basin. Both leaks were caused from deteriorated joint seal material. The leaking expansion joints also created further damage within the basin. Once water escaped through the joint, it migrated underneath the slab, eroding the substrate. This caused the basin to settle and sections began to pull away from one another, creating massive water loss.
SOLUTION: The facility was in the process of building a new tank but still had three months until completion. With such high water losses, the plant was on the verge of shutting down. The contractor was asked to slow the leaks in order for plant workers to keep up with the amount of water being lost. Realizing the urgent need to keep the plant operational, and the concern for wasting water during the second worst drought in the history of the Southeast, the contractor mobilized a crew within 48 hours of the initial call.
Chemical grout technicians used hydrophilic Prime Flex 900 XLV (extra low viscosity) to seal the expansion joints in both the exterior wall and basin. They used hydrophobic Prime Flex 920 to correct the settling and subsequent deflection of slabs from within the tank. Both of these products are proven to meet NSF/ANSI Standard 61 for contact with drinking water.
BENEFIT: Engineers estimated the cost of water being lost each day as $4,000 – 6,000, for a total of $130,000 per month. With the quick action on the part of the contractor and crew, all leaks were completely stopped within two and a half days. The municipality, engineers and plant personnel were able to continue operations without a single day of downtime.