Project Overview

• Prestressed floor, walls and roof
• Football field sized floor and roof slabs poured monolithically with no joints
• D115 Tank resulted in a 10% cost savings over the conventionally reinforced tank
• No measurable leakage during leak tightness testing

In recent years the City of Provo has experienced rapid population growth requiring 10 MG of additional drinking water storage capacity for their residents.  Therefore, the City sought the construction of two additional water storage tanks measuring 4 MG and 6 MG to support the increasing demand.

Due to the tank site geometry and spatial constraints, a rectangular tank solution proved effective to achieve the required tank capacities.  The team found that by pursing a DuraStor™ Tank (AWWA D115 Tendon Prestressed Concrete Tank) design saved the city approximately 10 percent over the conventionally reinforced 4 MG tank design.  Based on this cost-savings the team then designed the 6 MG tank D115 tank over a conventionally reinforced design.

Both tanks featured bi-axially prestressed floors, walls and roofs for assured watertightness.  Constructed in a high seismic region, the tanks also required robust connection details and increased prestressing to handle the seismic loads.

Tank #1 had 12” of soil cover on the roof with two of the four walls backfilled.  The other two walls were left exposed but included a rock pattern cast into the prestressed walls for aesthetic appeal.

Tank #2 a buried tank, features public tennis courts on the prestressed roof.  Threaded tendon couplers were installed in the floor, walls and roof to allow for the expansion of a second 4MG cell at the south end of the tank and the ability to connect the two cells together using post-tensioning systems.