Contributed by Eastsound Water Users Association general manager Paul Kamin.
Eastsound Water Users Association (EWUA) has begun using a new water filtration system at its three wells on Blanchard Rd.
The new filter unit has been added to EWUA’s Blanchard well field to improve both water quality and to increase production capacity. The three wells at the Blanchard well field have been historically impaired with higher than acceptable levels of manganese. While manganese is considered a “secondary contaminant” with no adverse health effects, it can lead to discolored water, and its presence has limited EWUA’s use of these wells in the past. Manganese is a naturally occurring element that is a common challenge found in Orcas Island groundwater.
The new filter system is producing high quality water. Manganese levels in water coming from the wells have been ranging from 0.30 mg/l to 0.18 mg/l (milligrams per liter). The State Department of Health’s water quality level for manganese is .05 mg/l. The new filter system is removing 97 percent of the manganese and test results of the water “going to system” are consistently 0.01 mg/l or lower.
The new filter system has also helped EWUA to access previously unusable capacity from these wells. Combined production from the wells was previously limited by the capacity of the older filter system. During the summer of 2010, EWUA could use no more than 20 gallons per minute from the Blanchard Wells. The normal operating rate was more often at 14 gpm. This summer, with the new filter, the facility has been able to be operated at 75 gpm. The added capacity currently helps relieve stress at EWUA’s other water sources such as Purdue Reservoir during peak summer demand and provides added backup capacity should the association experience a major leak or equipment failure elsewhere in the system. More importantly, the added capacity will provide service for several hundred new membership connections in the future.
The filter works by introducing chlorine into the raw water to help bring the manganese out of solution, then the water is forced through a series of proprietary sand and gravel-like layers of “media” that capture the manganese while allowing the water to flow through. The filter is automated to backwash the sequestered manganese to a waste tank every eight hours.
EWUA worked with “Filtronics”, a California-based company, to develop this filtration system. The association is planning to include similar Filtronics units at two other new water sources where manganese is already known to be present. The improvements to Blanchard facility represent an investment of approximately $250,000 of the association’s capital reserves. The new filter has eliminated over $5,500 in annual disposable cartridge filter costs associated with the system it replaced.
For more information, contact Kamin at 376-2127.
