Kennewick and Richland residents can’t depend on city water to irrigate their lawns this summer if an expected drought limits the availability of Kennewick Irrigation District water.
Kennewick and Richland lack the capacity to provide water to irrigate lawns on top of providing drinking water and water for firefighting.
Gov. Jay Inslee recently declared a drought emergency for the Yakima Basin, and KID may receive only an estimated 73 percent of its normal water allocation.
KID hopes to provide full water deliveries through May, said Jason McShane, engineering and operations manager. Most customers should have water by April 15. The irrigation district can’t start filling the canal system until April 1.
Water not used during the spring can’t be saved for the summer months because KID lacks the ability to store water for use later in the season, McShane said. But it still is important to use water efficiently this spring because the district is limited in the amount it can use during the irrigation season.
More than 16,200 KID customers are within the city of Kennewick’s boundaries. More than 4,100 are within the city of Richland. That includes a mix of homes and farms.
The possible irrigation use by KID customers alone could be greater than what Kennewick can provide for all city uses during a single day, said Gary Deardorff, Kennewick’s utility services manager.
Kennewick can provide about 23 million gallons of water per day for all city water use, Deardorff said. The city treats Columbia River water and groundwater for municipal use.
Winter demand tends to be between 5 and 8 million gallons a day but demand goes up in the summer, he said. Some Kennewick residents use city water for irrigation because they don’t have access to KID water.
The average demand for water use between April and September last year was 15.1 million gallons daily, with a peak demand of 18.9 million gallons, Deardorff said.
Residents who use city water to irrigate their lawn must have a backflow prevention device on their irrigation system to prevent any possible contamination of the city’s potable water, Deardorff said. Irrigation and well water should be used for lawns and gardens if at all possible.
“Our water system is not designed for continuous irrigation supply,” Deardorff said. “ If we find the demand on our system is approaching the limits of our production abilities, our Kennewick Municipal Code allows us to place restrictions on irrigation usage.”
An average Kennewick customer spends about $54 per month for city water to irrigate their lawn. However, the amount varies quite a bit depending on the size of yard, different landscaping and watering habits.
The city’s water usage rate is $1.17 per 100 cubic feet or 748 gallons of water, Deardorff said. Customers are charged for water use as measured by each water meter, regardless of what it is used for.
Richland residents who receive irrigation district water can’t switch to city water in a drought. The switch is against city law because Richland lacks the capacity to provide irrigation water in addition to drinking water, said John Finch, Richland’s water manager.
“We don’t have the capacity to start irrigating everything; we can’t do it,” he said.
Residents can use garden hoses to water flowers, but can’t switch their lawn irrigation systems to city water, Finch said. The city will contact landscaping and irrigation companies about the limitations and send out information to customers via utility bills.