Cheney water passes annual testing
When it’s in good supply — which is most of the time — Cheney’s drinking water continues to be some of the cleanest water around.
According to the city’s 2013 Annual Consumer Confidence Report, Cheney’s water tested below maximum contaminant level goals established by the federal Environmental Protection Agency as well as state goals, including contaminants produced as a by-product of water disinfection processes. Some contaminants such as lead were undetected in the water samples collected.
Public Works director Todd Ableman said the city has been conducting water quality testing for years, and couldn’t remember the last time a violation was reported.
Sampling methods and locations vary in accordance with requirements in the Washington Administrative Code. Ableman said sampling occurs at each of the city’s eight groundwater wells to assure adequate contact time for chlorine and fluoride, chemicals injected into the water system at each pump location to disinfect and as a dental additive. The sampling is usually done at a fire hydrant located near the well, but at least ahead of that water main’s first customer.
The amount injected is lowered or increased depending on the pump’s output, keeping both chemical residuals within accepted levels — 0.2 to 0.4 milligrams per liter for chlorine and 0.8 to 1.0 milligrams per liter for fluoride. Levels of both chemicals are tested daily.
Ableman said the city annually spends $30,000 to $40,000 on testing, along with about $12,500 for chlorine and another $5,800 for fluoride. Cheney’s wastewater treatment plant personnel perform some of the sample testing, with samples requiring additional testing qualifications sent to AAA Laboratories in Cheney and another outside firm.
“Between the three of us we meet the testing requirements,” Ableman said.
One of those tests is for turbidity, or water clarity. At times Cheney’s Water Department receives calls from residents complaining about brown water emerging from their taps. The discoloration is a product of residual mineral build up in the city’s 45-plus miles of water mains that become agitated and loosened during irrigation season, instantaneous high water demand or brief power outages.
Ableman said flushing the system usually alleviates the problem. Residents experiencing discolored water should run cold water or their irrigation system for 5-20 minutes to clear it up. If unsuccessful, he urged residents to contact the Water Department so they can flush the line.
The annual report also noted Cheney was able to account for 90 percent of the water it produced, losing only 10 percent to leaks, theft or other issues within the system. According to Water Department stats, the city uses on average 1.68 million gallons of water daily, 51,122,408 gallons monthly and 613,468,900 gallons annually.
Being 90 percent efficient in its water usage is important given measures other area municipalities have undertaken to protect aquifer systems that are being depleted. Medical Lake has entered into a water system inter-tie agreement with the city of Spokane in being able to use that municipality’s system in a water emergency, while Airway Heights’s wastewater treatment plant discharges its output, treated to Class-A drinking water standards, back into the ground to help recharge the West Plains aquifer.
“Although we share the same basalt aquifer, Cheney’s decline over the past 40 years has been an average of 0.5 feet (of water) per year,” Ableman said in an email.
John McCallum can be reached at firstname.lastname@example.org.