Editor’s note: This story is part one in a two-part series looking at water usage at the island’s athletic fields. This week the focus is on the VES Fields; the next article will focus on the school district’s fields.
When the irrigation season ended earlier this month, the Vashon Park District had used slightly more water than its permit allows at the VES Fields, but district staff say they intend to stay under the limit next year, and a state official indicated there is no current cause for concern.
“We know from monitoring that water quantity is not an issue,” said Doug Wood, a water resources hydrogeologist with the state’s Department of Ecology (DOE), “The water levels are not in danger.”
The DOE issued the district a permit to develop the water right at the fields complex in 2013 and set a limit of 9.2 “acre-feet” of water — nearly 3 million gallons — to be used from May through October. (An acre-foot is the volume of a sheet of water 1 foot deep on 1 acre of land.) In 2014, the district stayed considerably under that amount, and used less than 1,694,000 gallons, according to Jason Acosta, the district’s maintenance supervisor. This year, in a summer that was much hotter and dryer than typical, Acosta said the district exceeded its limit by 3 percent and used 3,088,000 gallons.
“The reasons are plainly obvious to anybody,” Wood said about the overage. “They had the worst possible summer they could have had.”
Now, the district must file an application for a new permit for the additional amount of water used and pay a $50 filing fee, Wood said. If the district stays under the limit next summer, it will not have to proceed with the additional permit. If it goes over again, however, it will need to obtain a new permit at a cost of about $15,000.
“Next year is fish or cut bait time,” Wood added.
At the park district, Executive Director Elaine Ott said she and Acosta take water conservation seriously and have worked to reduce water usage at the fields.
“Part of our mission statement is to be responsible stewards of natural resources,” Ott said.
For irrigation at the VES Fields, the park district draws all of its water from a well, relying on Heights Water for use only in the restrooms at the site.
In the past two years, Acosta has taken several steps to keep the fields healthy and green, he said, while trying to be conservation- minded, including consulting irrigation professionals, changing sprinkler heads, adjusting the system to shut off if it rains one-quarter of an inch or more and watering primarily at night to keep evaporation to a minimum. Additionally, based on advice from a consultant, this August he began using a plant-based product called Moisture Manager, designed to reduce watering needs by up to 50 percent or more. That proved successful, he said, and he plans to continue using it.
Water is a frequent topic on Vashon, and at least two commissioners for the park district board have expressed concern about the amount of water the VES Fields require. DOE’s Wood, however, said his agency is monitoring the situation and is not concerned.
Wood noted that Acosta called him early this month to tell him that the park district would exceed its limit.
“I couldn’t in good conscience say, ‘Let your fields die,'” Wood added.
Replacing grass that would have died as a result would have been expensive, he said, and there is ample water available, though he added he “absolutely advocates” the district take conservation measures.
The fields are located in one of the few watersheds on the island where new permits are still allowed, he noted, and data indicate there is plenty of water in that area for irrigation if the amount of precipitation does not decline.
Some 40 inches of rain fall annually in that part of the island, Wood noted, and given the size of the site, that translates to nearly 20 acre-feet of rain falling on park property. Of that, approximately 5 acrefeet re-charges the aquifer. That translates to the park district using twice the amount of water that typically falls as rain within its boundaries, but it draws from rain that falls in nearby areas as well.
“The 9 acre-feet (limit in the district’s permit) is not a lot of water when you consider how much water falls at the north end of the island,” Wood said in summary.
To determine appropriate water usage when issuing the permit, Wood said DOE officials relied on irrigation tables from the United States Department of Agriculture and the Washington State University Extension Program. The tables were not intended as guides for irrigating quick-draining, sand-based athletic fields, which the VES Fields are, and he said that difference likely also contributed to the overuse of water this summer. Additionally, the fields’ young grass, with little root growth, is more susceptible to drought stress than established grass.
At the park district, Acosta agreed that lack of root growth is a problem. An 8- to 12-inch root zone is optimal, but the current root zone is only about 4 inches, and use of the fields also makes a difference, along with the fact the fields are young.
“In the heavy use area, it is coming in a lot slower,” he said.
In order for DOE to issue a water right permit, four conditions must be met, Wood said. Water must be available, serve a beneficial purpose, not impair other water rights and not be detrimental to the public interest. At the VES Fields, Wood said, all those conditions were met, and no one from the island expressed concern during the public comment period.
Ongoing monitoring will indicate if water levels decrease beyond typical annual variations, he said, and if a problem arises, DOE will step in. He also noted that DOE works with climate change models from the University of Washington, and they indicate that Brainbridge Island, the Kitsap Peninsula and Vashon will see no reduction in precipitation through 2100.
Still, he said, he and other government officials are monitoring the water picture on Vashon, including weather patterns and climate change and their effects.
“It’s best to be prepared for the worst. We can prevent problems if it does occur,” he said.
