Project Overview

• Single floor slab and roof placements with no joints
• Downturned column and wall footings for ease of cleaning
• Constructed in tight space with as little as 5ft of space around perimeter of tank
• No measurable leakage during leak tightness testing

Kearns Improvement District, a water and sewer utility in Utah, decided to replace their older 1 and 2 MG tanks located at their facility. The District sought a single replacement tank measuring 192’ dia. x 24’ tall that would provide 5 MG of storage.

The project bidding documents allowed three tank alternatives including a conventional rebar tank design, a D110 Type 1 prestressed concrete tank and a D115 prestressed concrete tank. All general contractors submitted the D115 tank alternate as their lowest price option. The District then selected the D115 tank based upon its superior performance and low cost.

STRUCTURAL TECHNOLOGIES was selected to provide the structural design of the D115 tank, provide structural inspections, and supply and install the VSL post-tensioning systems and rebar used to reinforce the tank. A combination of unbonded single strand and bonded multistrand post-tensioning systems were used for tank construction.

One challenge of the project was the tight construction site. The District chose to build the new tank at their current facility and wanted to maximize the tank storage volume. In order to do so, the site was laid out with as little as 5 feet of space around the perimeter of the tank. Other tank design options would have required more space and costly excavation methods. The D115 tank construction method allowed for the tight site space at the most competitive cost.

The project was completed successfully and the leak tightness testing performed in February 2016 resulted in no measurable loss ensuring a watertight solution for the District.