Aquifer Health

Kitsap Water 101

What do the Olympic Mountains have to do with your drinking water? How does your septic system potentially help salmon? How might your lawn be harming our aquifers? Take a 5 minute tour of this “story map” and learn these and other interesting things about Kitsap’s water resources.

Kitsap Water 101 Story Map

Groundwater & Aquifers


Graphic showing Groundwater flow between unsaturated zones and saturated zones; Rechargin precipitation, recharge ditches, and saltwater intrusion flow into an aquifer. Groundwater from an aquifer feeds into a stream and discharges into the sea. Water that falls to the earth in any form continues its journey through the water cycle in different ways. It may run off into the storm drain, end up in a stream, a lake or Puget Sound. Some of the water will soak into the ground to become groundwater. Gravity will pull the water down through the spaces between the rocks, gravel, clay and sand that are under the ground. The water will join another area filled with water under the ground, called an aquifer. This is an underground storage area for water.

The water is in the tiny spaces around the rocks, gravel, sand and even clay pieces. The top of this area is called the water table. The water table may be close to the surface of the ground or many feet below the surface. Groundwater is always moving. Sometimes quickly, sometimes very slowly depending on the type of material in the aquifer. Groundwater is flowing toward a place to get to the surface like a stream, wetland, lake or Puget Sound.


For every 100 people in Kitsap County, 80 of them use groundwater that is pumped from wells. Groundwater is important and the groundwater that supplies our drinking water is restored by the rain, so when it isn’t raining we all need to be extra careful about how much water we use and waste! Also polution is an important consideration. Any substances put onto the surface or below the surface of the ground have a possibility to enter the water table and be pumped up through a drinking water well.

Wells in Kitsap County are drilled into three types of aquifers: unconfined, confined and perched.

  • Unconfined or water table aquifers are the upper most aquifer that recharges directly from the surface
  • Confined aquifers, also called artesian aquifers, are found beneath airtight layers. Artesian wells in confined aquifers have pressure on them from the layers of silt and clay – Some artesian wells can flow freely to the ground because of the pressure in the aquifer
  • Perched aquifers are confined aquifers that are formed on the top of clay deposits in the unconfined aquifer