By SCWS Team
Published February 17, 2026 · 10 min read
Drilling a well is a significant investment—typically $15,000-$40,000 or more. Hiring the wrong contractor can mean wasted money, poor water quality, or a well that doesn't meet your needs. These questions help you evaluate contractors and protect your investment.
Must-Ask Questions Checklist
- ☐ Are you C-57 licensed and insured?
- ☐ What's included in the written estimate?
- ☐ What drilling method will you use?
- ☐ What's the expected depth and yield?
- ☐ What if you don't hit water at estimated depth?
- ☐ Who handles permits?
- ☐ What's the timeline?
- ☐ Can you provide local references?
- ☐ What warranty do you offer?
Licensing and Insurance
"Are you licensed as a C-57 Well Drilling Contractor?"
In California, well drilling requires a C-57 license from the Contractors State License Board (CSLB). This license demonstrates competency through experience requirements and examination. Verify any license at cslb.ca.gov.
Red flag: Anyone who says licensing isn't required, offers to work "under the table," or can't provide a verifiable license number. Unlicensed drilling leaves you without recourse if problems occur.
"Do you carry liability insurance and workers' comp?"
Liability insurance protects you if drilling damages your property or a neighbor's. Workers' compensation protects you from liability if a worker is injured on your property. Ask for certificates of insurance and verify they're current.
Cost and Scope Questions
"Can you provide a detailed written estimate?"
A proper estimate should itemize:
- Drilling cost (per foot or total)
- Casing material and cost
- Pump and equipment specifications
- Pressure tank, controls, and fittings
- Permit fees
- Excavation and site work
- What's NOT included (electrical, waterline to house, etc.)
"What happens if you need to drill deeper than estimated?"
Geology is unpredictable. A good contractor explains their approach: Do you pay per foot for additional depth? Is there a maximum depth? At what point do they reassess? Get this in writing to avoid surprise costs.
"What's your payment schedule?"
Reasonable: A deposit (10-30%), progress payments, and final payment at completion. Red flag: Large upfront payments or full payment before completion. California law limits contractor deposits to $1,000 or 10%, whichever is less, for jobs over $7,500.
Technical Questions
"What drilling method will you use and why?"
Different methods suit different geology. Cable tool, air rotary, mud rotary, and reverse circulation each have applications. A knowledgeable contractor explains which method suits your site conditions and why.
"What's the expected depth and yield based on nearby wells?"
Good contractors research neighboring well records (available from the California Department of Water Resources) to estimate depth and yield in your area. They should give you realistic expectations, not promises they can't keep.
"What size casing will you use?"
Residential wells typically use 5" or 6" diameter casing. Larger diameter allows better yield and easier future service. Ask about casing material—steel vs. PVC, wall thickness, and why they recommend their choice.
"What pump and equipment do you recommend?"
Get specific recommendations: brand, model, horsepower, and why it suits your needs. Quality brands (Franklin, Grundfos, Goulds) cost more but last longer. Ask about the pressure tank, control system, and any treatment equipment.
Process Questions
"Who obtains permits and what permits are needed?"
Well drilling requires county permits in California. A good contractor handles permit applications, fees, and inspections as part of their service. Ask what permits are needed for your location.
"What's the realistic timeline?"
Drilling itself may take 1-5 days depending on depth. But permit processing, equipment delivery, and scheduling can extend the project to 2-6 weeks or more. Get a realistic schedule and understand what can cause delays.
"Will you provide a well completion report?"
California law requires drillers to file a Well Completion Report with the state documenting depth, geology, construction, and yield. You should receive a copy—this document is valuable for future service and resale.
References and Warranty
"Can you provide references for recent local projects?"
Ask for 3-5 references from the past 2-3 years, preferably in your area with similar geology. Call them. Ask about professionalism, timeline adherence, problem resolution, and overall satisfaction. Would they hire this contractor again?
"What warranty do you offer?"
Typical warranties cover workmanship for 1-2 years, while equipment warranties vary by manufacturer (often 1-5 years). Get warranty terms in writing. Understand what's covered and what voids the warranty.
Frequently Asked Questions
What license should a well driller have in California?
In California, well drillers must hold a C-57 (Well Drilling) contractor's license issued by the Contractors State License Board. This requires demonstrated experience and passing examinations. Verify the license at cslb.ca.gov. Also confirm they carry liability insurance and workers' compensation. Never hire an unlicensed driller—you have no recourse if something goes wrong.
How much does it cost to drill a well?
In Southern California, typical costs range from $15,000-$40,000+ for a complete system including drilling, casing, pump, and equipment. Drilling alone runs $30-$75 per foot depending on geology. Deeper wells (300-600+ feet common here) cost more. Get detailed written estimates that break down drilling, materials, and equipment separately. Be wary of prices significantly below market rate.
Do well drillers guarantee finding water?
Most reputable drillers don't guarantee water—geology is unpredictable. What they should offer: drilling to an agreed-upon depth, proper construction and casing, and transparent pricing if deeper drilling is needed. Some offer agreements where you pay per foot until water is found (with a maximum depth). Never trust a "guarantee" of specific yield—no one can promise that.
What questions should I ask a well drilling contractor?
Essential questions: Are you C-57 licensed and insured? What's included in the estimate? What drilling method will you use? What's the likely depth and yield based on nearby wells? What happens if you don't find water at estimated depth? What permits will you obtain? What's the timeline? Can you provide references? What equipment do you recommend? What warranty do you offer?
Ready to Drill?
We're a licensed, insured well drilling contractor serving San Diego and Riverside Counties. Free estimates with honest answers to all your questions.
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