An Unused Well Has One Year Before the Law Calls It Abandoned

Old ranch properties often carry a second well: the first one drilled, a stock well by a fallen windmill, or a casing nobody has pumped since the new well went in. The state's well standards say a well that has not been used for one year is considered abandoned, unless the owner shows an intention to use it again. An abandoned well must be destroyed properly.

Keeping a well on standby

San Luis Obispo County asks owners who want to keep an idle well to complete a Declaration to Maintain an Inactive Well and return it to Environmental Health. The form asks for a copy of the well completion report and a photo of the well. Owners missing that report can request it from DWR; finding your well log covers the steps.

The state standards also set conditions for a well kept in reserve. The cover must be locked, and watertight once the well has sat idle for more than five consecutive years. The well must be marked so it can be found, and the ground around it kept clear. Those are owner tasks; repairs to the casing or seal are not, and the state's well-owner booklet advises calling a licensed well driller rather than fixing a damaged well yourself.

When a well has to go

A well that is not kept under a declaration must be destroyed by a C-57 licensed well contractor, the county says. Destruction needs its own permit: it is unlawful to begin without Environmental Health approval, and the driller files the application for the owner. Within 60 days of finishing, the contractor must file a completion report with DWR, the same as for a new well.

The reason is groundwater protection. The State Water Board's well-owner booklet explains that unused wells can let contamination reach the drinking-water aquifer, and that destruction usually means pulling the casing where possible and filling the hole with cement or a similar material. For help choosing a contractor, see hiring a well or pump contractor.

Common questions

Does a stock well on my ranch count?

If it has gone a year unused and you have not filed the county declaration, the state treats it as abandoned. Ask Environmental Health whether to file or destroy it.

Which state law covers this?

State law and DWR's well standards set the one-year rule. The county form and DWR cite different Health and Safety Code sections, so ask the county which one it applies.

Sources

1. DWR — Combined Well Standards, Section 21, destruction of water wells — one-year rule, conditions for inactive wells
2. County of San Luis Obispo — Declaration to Maintain an Inactive Well — county form and attachments
3. County of San Luis Obispo — Water Well Destruction Permitting — permit required, driller applies
4. State Water Resources Control Board — A Guide for Private Domestic Well Owners — why unused wells are destroyed, how, and repairs by licensed drillers
5. DWR — Well Completion Reports — report within 60 days of destruction
6. County of San Luis Obispo — Private Well Owner Resources — declaration or destruction by a C-57 contractor