With a state drought proclaimed this year, the ongoing impact of climate change, and continued population growth on the Key Peninsula, will there be enough water to support the local population?
The short answer is probably yes.
According to state climatologist Guillaume Mauger, drought conditions this year, at least for western Washington, are nearly resolved.
“Snowpack was less than 75% of usual — an official mark to declare drought,”
Mauger said. “A warm, dry spring was predicted, but it turned out that it was relatively cool everywhere. It was dry in the eastern part of the state with about a normal amount of precipitation or even a bit more in the western part.” Summer, he said, was still predicted to be warm and dry, so the state did not lift its drought declaration.
In Washington State, about 40% of water comes from surface water sources: lakes, rivers and reservoirs. But in Water Resource Inventory Area 15 (WRIA15), which includes the Key Peninsula, the water supply is solely from groundwater. Rain falls, saturates the Earth to the level of the water table — which may change depending on geology and weather conditions — and percolates to recharge aquifers.
Aquifers are beds of waterbearing rock, and how water flows through those beds depends on the permeability and porosity of the rock. As glaciers advanced and receded, they left layers of rock, sand and rubble that are porous, which might alternate with confining layers of less porous material. Aquifers that are shallow enough and flow quickly enough are suitable for wells. Water from aquifers also flows to streams and directly into bodies of water like Puget Sound.
In 2014 the United States Geological Survey completed a study of the hydrogeology of the Kitsap Peninsula using data from more than 2,000 well logs, and although it did not include the Key Peninsula, it did include the Gig Harbor Peninsula. The information likely reflects the hydrogeology of the Key Peninsula. There are probably four aquifers of varying depths and thicknesses identified in the study that provide water to wells on the KP between the surface and bedrock that lies 1,000 to 2,000 feet below.
Anne Thebo, a hydrogeologist with the Climate Impacts Group at the University of Washington, said that groundwater flows from the Kitsap Peninsula toward the KP and to Puget Sound. Groundwater from Gig Harbor flows into Henderson Bay and Commencement Bay.
“It’s a complex system with multiple aquifers,” Thebo said.
“Though I can’t say for certain, it seems plausible that there is limited connectivity with the rest of the Kitsap Peninsula.” This means that water use in Port Orchard or Purdy will not likely have a significant impact on the water supply on the Key Peninsula.
If aquifer recharge matches what flows out — to wells or bodies of water — the water supply will remain adequate. The USGS data from 2012 showed that only about 4% of the water that was discharged from WRIA15 aquifers was withdrawn by wells. Sixty-six percent flowed to streams and 30% to Hood Canal and Puget Sound.
The 2016 Hirst Decision by the Washington State Supreme Court called for protection for those with existing water rights as well as the preservation of rivers and streams. The Tacoma-Pierce County Health Department, which approves new permits, has a policy designed to ensure that new wells don’t put existing wells at risk. No new wells are allowed in designated Urban Growth Areas, within the service areas of large public water systems such as the one that supplies Key Center, or close to smaller water systems or individual wells without an evaluation by a hydrogeologist.
In a written communication with the Key Peninsula News, the department stated, “Group A and B public water systems issue a Certificate of Water Availability for the proposed use, which we use to ensure that the water systems have capacity for the proposed development. Department of Ecology designates specific WRIAs to water withdrawal limitations and requirements. The Key Peninsula comes under the requirements of WRIA15.”
“Although there are areas of the state where water has been over-allocated, WRIA15 is not one of them,” Mauger said.
“We have not heard any evidence or been informed by our state partners, the departments of health or ecology, about any concerns about drinking water supply or safety,” said Jessica Gehle, division director of Environmental Health at TPCHD. “Of course, conserving water, especially during the summer months, is still important as good practice, as well as ongoing maintenance and upkeep of wells and water systems to avoid disruptions.”
TPCHD received a 5-year grant from the U.S. Centers for Disease Control to test for saltwater intrusion and arsenic and is testing local samples. Arsenic occurs naturally in soil and is a health risk, especially to children. It can be removed by filters. The combination of sea level rise with groundwater depletion increases the risk of intrusion. Water may be undrinkable, can cause corrosion, and can’t be used for irrigation.
High-risk areas for saltwater intrusion are along the shore of Taylor Bay and on the southeast shoreline of Von Geldern Cove. Areas of possible risk include Key Center, the southern shore of Von Geldern Cove, Penrose State Park, the western shore of Filucy Bay, Devil’s Head, and shoreline to the north of Whiteman Cove.
“We are here to help people,” Gehle said. “We are available by email, over the phone, and at the KC Coral office. We want to be sure that people on the Key Peninsula have access to us and that we can address their concerns.”
TPCHD is accepting water samples through Aug. 30. Get more information by email from ehdrinkingwater@tpchd. org or at tpchd.org/drinkingwater, or in person at the Key Center Community Council office on the third Thursday of each month.
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