Big water tank project on hold until warmer weatherNov 15, 2012 By Alejandra Silva, Staff Writer
The engineers and contractors working to build a 2 million gallon water storage tank near Airport Road met Tuesday with the Riverton City Council to explain the initial construction and progress.
The project was put together by Burns and McDonnell, the engineering company that designed the hydraulic model, and DN Tanks, the general contractors and tank contractors who represented the construction and also the design of the tank.
Company representatives said the new tank was designed based on the amount of "fire flow" needed and future expansion projections.
Fire flow is the water needed to fight fires in a given area.
"We did it so that the city can have a lot of flexibility in using this tank and pump station," Burns & McDonnell associate Andy Hundley said. "It looks complicated, but it's relatively simple."
The new water tank will get water from the pump station and well already in place at Riverview Road and Mountain View Drive. Hundley said separate phases were designed to allow for the creation of pipe systems that would help water run from the existing water treatment tank into the new one.
During phase one, pipe systems would be created to serve the city's various pressure zones, many of which require more storage capacity and increased water pressure.
Phase two consisted of a different set of pipes that would be installed directly into the new water tank. Phase three is the pumping facility phase.
Concrete, steel tank
Riverton already has several steel water tanks, but DN Tanks regional manager David Bain said the new tank they have chosen is called a pre-stress tank made from both concrete and steel. Bain said steel tanks are very water tight, but they tend to crack and are more vulnerable to corrosion. He also said steel tanks require repainting over time, which can get expensive.
Bain said concrete tanks do not require repainting, and they can be buried or tucked under a hill --which is how the new tank will end up, according to the photos Bain provided.
"Concrete itself is relatively stable," Bain said. "We've been building tanks since the 1930s, and we can tell you that we expect that you won't be putting money into this for the next 75 years."
Hundley said that the decision to choose this type of tank will save the city more than $215,000. Hundley said they used local materials, labor and equipment throughout the tank project.
Construction of the tank has been put on hold for the winter. Bain said the colder temperatures actually are good for certain parts of the tank. He said the wall and dome panels are currently covered with large "thermo blankets." The surface has been covered with water to allow the concrete to cure slowly over time.
Construction is expected to resume in March. By then, phase three will begin, with the tank's wall lifted into place through a process that will take several days. Hundley said the project should be completed in September 2013.