Critical aquifer recharge areas

The goal of establishing critical aquifer recharge areas (CARA) is to protect a community’s drinking water by preventing pollution and maintaining supply. We help cities and counties comply with CARA requirements that are required by the state Growth Management Act.

Why does groundwater protection matter?

Washington state citizens get at least 60 percent of their drinking water from groundwater. Most people in rural areas get their drinking water from groundwater.

What is our role?

We provide technical assistance and review for counties and cities to help them protect their groundwater. Cities and counties must identify where important groundwater resources are so they can protect their drinking water supply.

These Critical Aquifer Recharge Areas are required under the Growth Management Act.

Help us improve our groundwater guidance

We are seeking feedback on the outdated Critical Aquifer Recharge Area guidance and would like your feedback. We will be accepting comments until Dec. 15.  We are interested in what changes and/or additions we need to consider to help local jurisdictions protect Critical Aquifer Recharge Areas under the Growth Management Act.

There are two ways to give us feedback. You can fill out our quick survey that includes an open box for general comments or download this excel sheet to give us detailed comments by topics within the guidance. After you fill out the spreadsheet upload the spreadsheet to our survey after question 8

Please feel free to skip any question or submit your feedback anonymously.

Next steps: We will organize the comments we receive around themes and use them to help us focus on topics for the guidance update. After the close of the comment period we will review comments and provide an overview of what we heard. We will send out notice about the next steps to anyone who provided contact information.


Contact Laurie Morgan:

How to protect groundwater resources

The Growth Management Act defines CARAs as “areas with a critical recharging effect on aquifers used for potable water.” The following steps characterize where groundwater resources are important to understanding how to protect them.

  • Identify where groundwater resources are located.
  • Analyze the susceptibility of the natural setting where groundwater occurs.
  • Inventory existing potential sources of groundwater contamination.
  • Classify the how vulnerable the groundwater is to contamination events.
  • Designate areas that are most at risk to contamination events.
  • Protect groundwater by minimizing activities and conditions that pose contamination risks.
  • Ensure that contamination prevention plans and best management practices are followed.
  • Manage groundwater withdrawals and recharge impacts to:
    • Maintain availability for drinking water sources.
    • Maintain stream base flow from groundwater to support in-stream flows, especially for salmon-bearing streams.

We can provide technical assistance to local governments working to protect the functions and values of a community’s drinking water by preventing pollution and maintaining supply.

Our Critical Aquifer Recharge Areas Guidance Document helps you understand what is required for protecting local groundwater resources under the Growth Management Act.

Agricultural operations can help protect CARAs through the Voluntary Stewardship Program.