- Healthy Places
- Drinking Water & Wells
- Maintaining Your Well
Maintaining Your Well
How to Monitor & Maintain Your Well
Keep your yourself and your family healthy by maintaining your well.
- Locate your well. Determine if it is a dug well or drilled well. Dug wells are more susceptible to contamination from surface water runoff, because they are shallower. Old and abandoned wells are a safety concern and need to be decommissioned. Report any unused or abandoned wells to the Department of Ecology.
- Inspect the wellhead. Check the cap, seal, and area around the casing for leaks, making sure the access port is plugged. If present, the well vent should be inverted and screened. The well casing should extend one to two feet above the ground (or flood level); mound around the casing with clay to prevent surface water from collecting. For repairs, contact a licensed well driller.
- Test your water. This should be done yearly to check for bacteria and every three years for nitrate – more often if your well is hand dug.
- Keep records. Important records include well installation, repairs, pump tests, and water quality results.
- Protect the wellhead. Keep surface water runoff away from the wellhead, which should be upslope from potential contamination sources. A curtain drain upslope can be installed to divert runoff. Contact us if you are going to install a new or replacement well or septic system.
- Buffer the well. Create a safe zone around the well (a minimum of 100 feet), free from potential pollutants such as animal waste, chemical fertilizers, pesticides, etc. Don’t store any chemical products in a well house.
- Protect the soil. Oil, gasoline, and household chemicals can seep into the soil, contaminating the water. Dispose of your hazardous waste properly.
- Garden responsibly. Avoid fertilizers and pesticides within 100 feet of your well. For pest control, consider biodegradable products, physical barriers, beneficial insects, and companion planting. If chemicals are necessary, use them sparingly, installing a backflow prevention device on hose bibs for mixing. Avoid over watering to slow chemical movement into the soil and ground water.
- Check livestock. Animals and their enclosures should be kept at least 50 feet from a drilled well and 100 feet from a dug well.
For additional information on how to care for your private well, review the Information for Private Well Owners document.
How to Disinfect your Well
Review the recommended procedure for well disinfection document.
Arsenic in Your Well
Arsenic is naturally occurring in the Snohomish County region, and measured arsenic levels in groundwater and wells vary over time. The Environmental Protection Agency Maximum Contaminate Level (MCL) Standard for arsenic in drinking water is 0.01 mg/L or 10 parts per billion (ppb).
Learn more on the water testing page.
Signs of Damage
- Cracked well casing
- Cracked well caps
- Cracked, brittle, or deteriorated well cap seals
- Screen vents with holes or signs of deterioration
Review some simple fixes for wellhead openings.
Decommissioning a well
Wells no longer in use can lead to contaminated groundwater and pose a safety risk to children, adults, and animals.
Abandoned wells may be found in old pump houses, storage sheds, old detached garages, or small building structures. Hand dug wells can often be found in lowland areas near surface water.
These are the signs of an old, abandoned well:
- A steel, 6-inch diameter, well casing.
- Old concrete or brick-lined structures.
- Old water system components (pumps, plumbing, and pressure tanks).
- Open space under pump house floors.
- Wooden or cement hatch-like openings to vaults and wellheads.
If you have an abandoned well that is no longer in use, it is a safety concern, and you are required to decommission it. You will need to contact the Department of Ecology and a licensed well driller to do this.