On July 19 2003, The City of Fairmont Utilities Water Filtration plant became the largest ultra membrane water treatment plant east of the Mississippi. This "zeeweed” process technology produces high quality treated water by drawing raw water through immersed hollow fiber membrane modules that have nominal and absolute pore size of 0.035 and 0.1 microns respectively. This ensures that particulate matter greater than 1 micron in size, including Giardia Cysts and Cryptosporidium oocycts, cannot enter the treated drinking water.
At this time the plant can produce a maximum of 15 million gallons per day (MGD) using 5 zeeweed trains.
A programmable logic controller automates the operation of the process. The flow of treated water through the system is regulated according to the water level in the clear wells. The level in the clear wells are measured by a pressure-sending unit and the flow rate from the permeate pumps are adjusted using variable frequency drive units to match the water demand from the distribution system. The treated water flows from each zeeweed process tank membrane compartment through the membrane modules assisted by the VFD-controlled permeate pumps that generate a low pressure vacuum that draws the permeate "treated water" through the membranes.
If the water level in the clear wells decreases, the pump capacities increase. And conversely if the water levels in the clear wells increase, the pump capacities decrease.
About the Plant
The City of Fairmont’s new 15.0 MGD water treatment facility at Morris Park along Pleasant Valley Road is a new state-of-the-art facility, which features immersed ultra filtration membrane technology. The new plant was constructed adjacent to the existing treatment plant, of which portions are in excess of 100 years old. Membrane technology provides nearly a 100% barrier against waterborne pathogens, including cryptosporidium, and it produces high quality, aesthetically pleasing, safe drinking water.
The immersed membrane operates under a low negative pressure (vacuum) system in an open tank design. This facility is one of the largest immersed membrane potable water treatment plants in the United States.