Design wellhead protection
Most well contamination enters at the top. A sealed, raised wellhead with drainage away from it is cheap insurance for water quality.
How
- Specify a sanitary or vermin-proof well cap with a gasket that seals the casing while letting air in, as Penn State recommends.
- Grade the ground so surface water drains away from the casing (US EPA).
- Never cut the casing off below ground level (US EPA). Keep it above flood level and check your local code for the minimum height. Example, Minnesota (USA): at least 12 inches (305 mm) above the ground, floor or slab, and possibly 5 ft above the regional flood level in flood-prone areas.
- Ask the driller to grout the space around the casing to stop surface water running down the outside.
- Fence or mark the wellhead area and keep chemicals, fuel and animal waste out of the protection zone.
- Plan how the pump cable and pipe exit through a sealed pitless adapter or sealed cap, not an open gap.
Sources
- Protect Your Home's Water. US EPA, accessed 2026-11
- Protect Your Wellhead to Safeguard Drinking Water Supplies. Penn State Extension, accessed 2026-11
- Wellhead requirements (fact sheet). Minnesota Department of Health, accessed 2026-11