Wells · In brief
Before You Hire Someone to Work on Your Well
When hiring a well or pump contractor, check for a C-57 Well Drilling license on the state board's site; any job of $1,000 or more, or needing a permit, requires a licensed contractor.
By the Ranch House Water desk · Updated · 3 min read
Most well work on a rural property, from drilling and destroying wells to pulling and replacing a submersible pump, is licensed work in California. The state license board's C-57 Well Drilling class covers contractors who install and repair wells and pumps. San Luis Obispo County adds its own requirement: a driller who files well permits must also carry a $25,000 surety bond with county Environmental Health.
Match the license to the job
Three classes come up on rural water systems. C-57 covers wells and well pumps. C-36 Plumbing covers the house side: supply piping, drains, water heaters and water conditioning equipment. C-42 Sanitation System covers septic tanks and sewage disposal. A project that spans a well, a tank and the house may need more than one.
Check any name at CSLB License Check before you sign. The county's well owner checklist puts it simply: use licensed or certified drillers and pump installers whenever a well is built, a pump installed or the system serviced.
Money and paperwork
Since January 1, 2026, the state's minor-work exemption stops at $1,000, and only for work that needs no building permit. At $1,000 or more for labor and materials together, or for any permitted job, the person must be licensed. Splitting one job into smaller contracts to stay under the line is not allowed.
Up front, the most a contractor may request or accept is the smaller of $1,000 and one-tenth of the total, the CSLB says on its home page. Later payments should track work completed or materials delivered. Keep the scope, price and schedule in writing, and keep the permit and the well completion report the driller files with DWR; finding your well log covers that record. For rebuilding after a wildfire or other declared disaster, the CSLB says contractors must use a fixed-price contract.
For the wider picture of well ownership, see living on a private well, and for an idle second well, inactive and abandoned wells.
Common questions
Can I fix a pressure switch myself?
No. The switch box carries live wiring, and adjusting or replacing it is work for a licensed well or pump contractor. Your part is switching the pump breaker off and noting the symptoms.
What should a well bid include?
Ask for the license number, proof of the county bond for drilling, who pulls the permit, and the payment schedule, all in writing.
Sources
- CSLB — C-57 Well Drilling Contractor — scope of the well drilling license
- CSLB — C-36 Plumbing Contractor — plumbing scope
- CSLB — C-42 Sanitation System Contractor — septic scope
- Business and Professions Code section 7048 — $1,000 minor-work limit, effective January 1, 2026
- CSLB home page — down payment limit, fixed-price disaster contracts
- County of San Luis Obispo — Water Well Construction Permitting — C-57 license and $25,000 bond for drillers
- County of San Luis Obispo — Well Owner's Checklist — use licensed drillers and pump installers