Loading please wait

Loading please wait
Sign In
Island County > Public Health > Environmental Health > Hydrogeology > Seawater Intrusion Source Monitoring
​​

Seawater Intrusion Source Monitoring

Island County Code 8.09.099 (Seawater Intrusion Protection) is designed to help protect our aquifers / drinking water from issues related to seawater intrusion.  One of the tools incorporated into the code is the development of seawater intrusion risk ratings for areas of the county.  Areas are classified as being either 'low', 'medium', 'high', or 'very high' risk fo​r seawater intrusion based on water level elevation and chloride concentration data from all wel​ls located within 1/2 mile of the point in question.  Public water system (3 or more connections) sources that are classified as having elevated seawater intrusion risk (medium, high, or very-high) are required to monitor water quality in those sources.  A listing of all known public water systems sources, and their seawater intrusion risk ratings can be found HERE (last updated 09/19/2017).

When monitoring of a well is required, the well needs to be sampled twice per year, during the months of April and August.  Samples need to be submitted to a state-certified laboratory, and analyzed for chloride and electrical conductivity.  Samples are required to be collected from each source (that has elevated risk rating), not combined wellfield sources.  In order to get credit for the monitoring, samples should be labeled as 'compliance' and the water system ID (PwsID) and source number must be included. 

An SWI Rating of "ND" means there is insufficient data available to calculate a rating at this location.  Monitoring is not required in this situation (Monitoring Required = "No").  If however Monitoring Required = "No*" then based on available information, ICPH recommends that monitoring be conducted (although it is not required).​

​More information regarding seawater intrusion can be found in the Seawater Intrusion Topic Paper.  If you have questions regarding seawater intrusion and sampling requirements, please contact Doug Kelly.  ​​​

Island County

Copyright Island County. All Rights Reserved 2017

Site Disclaimer | Contact Us


Main Offices

Whidbey Office
1 NE 7th Street
Coupeville, WA 98239

Camano Office
121 N East Camano Dr
Camano Island, WA 98282

Helpful Numbers

Main Line: (360) 678-5111
Sheriff: (360) 679-7310

Juror Recordings
Superior Court: (800) 254-2755
District Court: (800) 946-9765

Island County Directory