How far must a well be from a septic system in California?

California state minimum is 50 feet from septic tanks and 100 feet from leach fields, but many counties require greater distances. San Diego County requires 100 feet from any septic component. Riverside County varies by area. In poor soil conditions or fractured rock, even greater distances may be required. These setbacks protect groundwater from sewage contamination.

What are setback requirements from other contamination sources?

Common setback requirements include: 100 feet from animal enclosures/feedlots, 100 feet from underground fuel storage tanks, 50 feet from surface water bodies, 100 feet from pesticide/fertilizer storage, 200 feet from landfills or dumps, and specified distances from cemeteries and industrial sites. Your county environmental health department can provide specific requirements.

What if my property can't meet setback requirements?

Options include: requesting a variance (may be granted with additional conditions like deeper casing), relocating the septic system, connecting to public water if available, or purchasing access to neighboring property for well location. Variances are evaluated case-by-case and may require enhanced well construction or additional water testing.

Well Setback Requirements California: Distance Rules for Well Placement

Q: How close can a well be to a property line?

Typical minimum is 5-10 feet from property lines, but this varies by county. Some counties allow 10 feet with neighbor written approval, or require 50 feet without approval. The setback prevents wells from being too close to neighbors' septic systems or contamination sources. Check with your county for specific requirements.

Setback requirements determine where you can legally locate a well on your property. These distance rules protect your water supply from contamination sources like septic systems, animal waste, and chemical storage.

California Setback Summary

Contamination Source	State Minimum	San Diego Co.	Notes
Septic tank	50 ft	100 ft	Counties may require more
Leach field	100 ft	100 ft	Most critical setback
Seepage pit	100 ft	100 ft	Same as leach field
Property line	5 ft	10-50 ft	Varies with neighbor consent
Surface water	50 ft	50 ft	Streams, ponds, etc.
Animal enclosures	100 ft	100 ft	Horses, chickens, livestock
Fuel tanks	100 ft	100 ft	Underground or above-ground
Chemical storage	100 ft	100 ft	Pesticides, fertilizers

Important: Local Requirements Vary

Always check with your specific county. San Diego County's 100-foot septic setback is stricter than state minimums. Your well driller will know local requirements.

Why Setbacks Matter

Setbacks protect groundwater from contamination that can travel through soil:

Septic systems: Sewage contains bacteria, viruses, nitrates, and pathogens
Animal waste: Concentrated nitrogen, bacteria, parasites
Fuel storage: Petroleum products contaminate groundwater for decades
Property lines: Ensures distance from neighbors' contamination sources

Finding a Valid Well Location

Identify all contamination sources: Your septic, neighbors' septics, animal areas, fuel tanks
Map setback circles: Draw required distances on your site plan
Find overlap-free areas: The well must be outside all setback zones
Consider access: Drill rig must reach the location
Verify with county: Submit site plan for approval

When You Can't Meet Setbacks

On small parcels, meeting all setbacks may be impossible. Options include:

Variance request: County may grant exception with enhanced construction (deeper sanitary seal, additional testing)
Relocate septic: Sometimes more cost-effective than well variance
Public water connection: If available, may be required
Neighbor easement: Permission to locate well on neighboring property

Frequently Asked Questions

How far must a well be from a septic system?

State minimum is 50 feet from septic tanks, 100 feet from leach fields. San Diego County requires 100 feet from any septic component. Check your specific county requirements.

How close can a well be to a property line?

Typically 5-10 feet minimum. Some counties allow closer with neighbor written approval, or require 50 feet without approval.

What if my property can't meet setbacks?

Request a variance, relocate the septic system, connect to public water if available, or seek neighbor easement.

Need Help Finding a Valid Well Location?

We can evaluate your property, navigate setback requirements, and find the best well location.

Call (760) 463-0493

Related Guides

California Permit Process

Complete permit guide.

Preventing Contamination

Why setbacks protect your water.

Well Setback Requirements