DBA was hired to construct a new sediment tank at the Cholla Power Plant in Joseph City, Arizona. The sediment tank collects water from the plant that is pumped in through a series of pipes and pumps, separating the sediment from the water into one of two chambers within the structure. The clean water flows over the wall into the second chamber and out the top of the structure into a larger basin to be reused. The sediment sinks to the bottom of the first chamber where it can then be removed.
The heavily reinforced concrete structure was 43′ long by 23′ wide and 15′ deep extended with a two-foot thick concrete foundation. The walls were 18″ thick and could only be poured in place for 44 linear feet at a time in order to install heavy rubber waterstops at every joint. The shoring used for the structure were pre-engineered EFCO forms that were reconfigured and reused for each section of the tank. Once the floor and walls were complete, crews constructed a concrete deck on top that supported the pumps.
Shortly after the tank was constructed, DBA was asked to construct a rebar reinforced concrete slab alongside the top of the structure to accommodate the sediment removal operations.