Chelan County Water Mitigation Program
When you apply for a new building permit through Chelan County Community Development, your drinking water well, spring, or surface water connection will need to be reviewed to ensure senior surface water and groundwater water rights are being protected. See this page for more information: County of Chelan, Washington.
Private Water Systems
Private Water Systems are those systems intended to serve one or two residences, primarily single family dwellings. Prior to receiving an onsite septic permit for a new building (home or accessory dwelling unit), applicants must complete a Private Water Review to demonstrate access to an adequate water supply. An adequate water supply is a state requirement for development. RCW 19.27.097 Building Permit Application - Evidence of Adequate Water Supply.
To complete a Private Water Review, please fill out the Private Water Review Application or in person assistance with application is available at CDHD.
A drilled well is most common source to show an adequate water supply for development. A drilled well must meet the minimum standard of 400 gallons/day/connection. A Well Log is most common method to determine the yield and drawdown, typically an air lift test is used. In the event a Well Log is not available, a well pump test must be completed. Methods to perform the pump test are referenced Per WAC 173-160-321.
The well pump test must be conducted for a period of at least one hour. Please reference the CDHD Flow Test Capacity guidance document for detailed explanation.
In addition to the Well Log or Pump Test, water samples of the well are required. The water samples required are Coliform (bacteria) and Nitrates. The primary lab in our area is Anatek Labs - Wenatchee. For a complete list of licensed laboratories refer to Washington Department of Ecology Lab Search
Coliform samples must be collected within one year of the application and for approval must be negative or absent results. If positive results are confirmed then conduct disinfection of well and resample. Consult with Well Servicer or refer to Positive Coliform Instructions for disinfection process.
Nitrate samples must be collected within 3 years of application. If results are 10ppm or higher, the MCL – maximum contaminant level, a Notice to Title is required. Please refer to our fact sheet on Nitrates to know the health risks associated with high nitrate levels.
A 100’ sanitary control area is required to protect the well from potential contamination. Sanitary Control Area Fact Sheet
Surface water sources are acceptable with valid water rights. Contact Washington Department of Ecology – Central Regional Office for details. Water rights - Washington State Department of Ecology
Common surface water sources are lakes and streams. The surface water source is required to have continuous disinfection and a Notice to Title . Please reference CDC Guide to Drinking Water Treatment Technologies for Household Use
Dug Well or springs are acceptable sources of adequate water supply. The same requirement of 400 gallons/day/connection apply for dug wells or springs. Additionally, dug wells are very shallow and are highly susceptible to contamination as are springs therefore continuous disinfection is required and a Notice to Title.
Hauling Water is also an acceptable source of providing an adequate water supply. However, several criteria must be met to allow hauling water as an approved water source.
- Evidence of an inadequate water supply – dry well log or the area is known to lack water availability.
- Water System Design – include Cistern capacity and manufacturer specifications, pump data (if applicable) and treatment and/or filtration methods.
- Site Plan
- Notice to Title
For General information regarding Private Wells refer to Important Information for Private Well Owners (wa.gov)
