Shallow Well Drilling in San Diego County
When Shallow Wells Work (And When They Don't)
SC By SCWS Team | February 10, 2026 • 15 min read
When property owners start researching well drilling, many hope they'll discover their property can support a "shallow well"—an affordable, simple water solution that doesn't require drilling hundreds of feet into bedrock. While shallow wells do exist and work well in certain geological settings, the reality in San Diego County is that most residential properties require deep wells to reach reliable water sources. Understanding the difference between shallow and deep wells, knowing when each is appropriate, and setting realistic expectations for your property is essential before you begin any well drilling project.
💡 Reality Check
Most San Diego County properties require wells 200-500 feet deep. Truly shallow wells (<100 feet) are rare and limited to specific geological areas with high water tables.
What is a Shallow Well?
The term "shallow well" doesn't have a universally standardized definition, but in the well drilling industry, it typically refers to wells less than 50-75 feet deep, with some definitions extending to 100 feet. Shallow wells tap into unconfined aquifers—porous layers of sand, gravel, or rock near the surface that hold groundwater above an impermeable layer.
Shallow Well Characteristics
- Depth: Typically 25-100 feet (vs. 200-600+ feet for deep wells)
- Water source: Unconfined surface aquifers
- Construction: May use larger diameter casing (6"-8")
- Pump type: Often use jet pumps rather than submersible pumps
- Drilling time: 1-2 days vs. 3-7 days for deep wells
- Cost: Significantly less expensive ($8,000-$18,000 vs. $25,000-$50,000)
Deep Well Characteristics
- Depth: Typically 200-600 feet (can exceed 800 feet in some areas)
- Water source: Confined or bedrock aquifers
- Construction: Typically 6" diameter with steel casing to bedrock
- Pump type: Submersible pumps designed for deep installations
- Drilling time: 3-7 days depending on depth and geology
- Cost: $25,000-$50,000+ depending on depth and site conditions
Where Shallow Wells Work in San Diego County
San Diego County's geology is dominated by crystalline bedrock (granite and metamorphic rocks) with relatively deep water tables. However, certain areas have conditions favorable for shallow wells:
Alluvial Valley Floors
Ancient river valleys filled with thousands of years of sand, gravel, and sediment deposits can hold substantial groundwater at shallow to moderate depths. Areas like portions of:
- Santa Ysabel Valley
- San Luis Rey River valley
- Lower San Diego River valley
- Sweetwater River valley
- Tijuana River valley
Properties directly on valley floors—especially near historic stream courses—may find water at 50-150 feet. Even so, many valley properties still require deeper drilling (200-300 feet) for adequate flow rates and reliability during dry periods.
Coastal Areas with High Water Tables
Some coastal valleys and low-lying areas near the ocean have shallow water tables due to proximity to sea level and groundwater flow toward the coast. However, shallow coastal wells face significant challenges with saltwater intrusion and contamination, making them risky for long-term residential use.
Agricultural Areas with Historic Groundwater Use
Some agricultural valleys in North County (Pauma Valley, parts of Valley Center, Bonsall valley floors) have historically supported shallow agricultural wells. However, decades of groundwater pumping have lowered water tables in many of these areas, and new wells often require deeper drilling than older wells drilled 30-50 years ago.
Realistic Expectations by Region
- Coastal valleys: Shallow wells possible (50-150 ft) but saltwater intrusion risk
- Inland valleys (Ramona, Valley Center valley floors): Moderate depth wells (150-300 ft) more typical
- Foothill and hillside areas: Deep wells required (300-500+ ft)
- Granite-dominant inland areas: Deep bedrock wells necessary (350-600 ft)
- Mountain communities (Julian, Palomar): Deep wells (400-800 ft) standard
Advantages of Shallow Wells
When conditions support shallow wells, they offer several advantages:
Lower Drilling Costs
The primary advantage is cost. Drilling 60 feet versus 400 feet makes a dramatic difference. A shallow well might cost $10,000-$18,000 complete, while a deep well on the same property could cost $30,000-$45,000. For property owners on tight budgets, this difference can be decisive.
Faster Installation
Shallow wells can often be drilled and completed in 1-2 days versus 3-7 days for deep wells. If you need water quickly, shorter installation time is beneficial.
Easier Maintenance
Pulling and replacing pumps in shallow wells is simpler and less expensive than servicing deep well pumps. A shallow well jet pump located above ground is easier to access and service than a submersible pump at 300-400 feet depth.
Lower Pumping Costs
Pumping water from 50 feet requires less energy than pumping from 400 feet, resulting in lower electricity costs over the well's lifespan.
Disadvantages & Limitations of Shallow Wells
While attractive in certain situations, shallow wells have significant limitations that often make deep wells the better long-term choice:
Higher Contamination Risk
Shallow aquifers are more vulnerable to surface contamination. Septic systems, agricultural runoff, pesticides, and surface pollutants can more easily reach shallow groundwater. Deep wells drilled into confined bedrock aquifers are naturally protected by hundreds of feet of rock layers.
Susceptibility to Drought
Shallow water tables fluctuate dramatically with rainfall patterns. During San Diego's frequent drought periods, shallow wells can go dry or produce inadequate flow rates, requiring deepening or replacement. Deep bedrock aquifers are more stable and less affected by short-term weather patterns.
Lower Flow Rates
Shallow aquifers often can't sustain high flow rates. If you need 10-15 gallons per minute for a large household or small farm, shallow wells may not provide sufficient capacity. Deep wells drilled into productive fracture zones in bedrock can yield higher sustained flow rates.
Limited Lifespan
Shallow wells often have shorter productive lifespans than properly constructed deep wells. Changes in groundwater levels, nearby pumping by other wells, or aquifer depletion can render shallow wells unproductive. Deep bedrock wells properly constructed can last 30-50+ years.
Permit & Regulation Challenges
Some jurisdictions have restrictions on shallow well construction due to contamination concerns. San Diego County requires setbacks from potential contamination sources, and these setback requirements can make shallow well siting difficult on smaller properties.
When Deep Wells Are Necessary
For most San Diego County properties, deep wells aren't just preferable—they're necessary. Here's why:
Granite Geology
Much of inland San Diego County sits atop the Southern California batholith—a massive body of granitic rock. In granite terrain, groundwater exists in fractures, joints, and weathered zones within the bedrock, typically at depths of 200-600+ feet. There's simply no water at shallow depths in these areas.
Hillside & Elevated Properties
Properties on hillsides, ridgetops, or elevated terrain have deep water tables due to elevation and drainage patterns. Water flows downhill underground just as it does on the surface, so hillside properties must drill deeper to reach it. If your property has views or sits on elevated ground, expect deep drilling requirements.
Reliability Requirements
If you're relying on a well as your primary water source for your home, livestock, or irrigation, the reliability provided by deep bedrock wells is essential. Shallow wells that run dry during summer or drought years aren't acceptable for critical water needs.
Property Value & Investment
Real estate values in San Diego County are high. When you're investing in property worth hundreds of thousands or millions of dollars, spending an extra $15,000-$20,000 to get a reliable deep well rather than a marginal shallow well is a sound investment. A property with a proven reliable well is more valuable than one with a questionable shallow well that may fail.
⚠️ Beware "Cheap Shallow Well" Promises
If a driller promises a cheap shallow well without thoroughly assessing your site's geology and water availability, be skeptical. Reputable drillers assess actual conditions and provide honest recommendations, even if it means explaining that deeper drilling is necessary.
Cost Comparison: Shallow vs. Deep Wells
Example: Shallow Well (When Possible)
Depth: 60 feet
Drilling: $3,500
Casing: $1,800
Jet pump & system: $2,500
Permits & completion: $800
Total: ~$8,600
Note: This scenario only works in favorable valley locations with proven shallow water availability.
Example: Typical Deep Well
Depth: 350 feet
Drilling: $17,500
Casing & grouting: $5,200
Submersible pump & system: $6,800
Permits & completion: $1,200
Total: ~$30,700
This represents typical costs for inland granite-area properties—the reality for most of San Diego County.
While deep wells cost significantly more upfront, they provide reliability and longevity that often make them more cost-effective over time when you factor in the risks of shallow well failures and replacement costs.
How We Determine If Shallow Drilling is Feasible
During our free site assessments, we evaluate multiple factors to determine whether shallow or deep drilling is appropriate for your property:
Geological Assessment
- Review geological maps showing rock types and formations
- Assess surface geology visible at your property
- Evaluate topography and elevation
- Identify your location relative to known aquifer systems
Nearby Well Data
- Research existing wells in your immediate area
- Review completion reports filed with the state
- Note depths, flow rates, and construction details of nearby wells
- Talk to neighbors about their well performance (with your permission)
Water Needs Assessment
- Determine your required flow rate (household size, irrigation needs)
- Assess whether shallow aquifers could sustain your demand
- Consider future needs (additions, landscaping, etc.)
Risk Assessment
- Evaluate contamination risks (nearby septic, agriculture, etc.)
- Consider drought reliability needs
- Assess long-term water security requirements
Based on this comprehensive assessment, we provide honest recommendations. If your property can support a shallow well safely and reliably, we'll tell you. If deep drilling is necessary, we explain why and provide accurate cost estimates.
The Hybrid Approach: Moderately Deep Wells
Sometimes the best solution isn't the shallowest possible well or a very deep bedrock well, but rather a "moderately deep" well—typically 150-250 feet—that balances cost and reliability:
- Deeper than shallow wells, avoiding most contamination risks
- Taps lower-level alluvial aquifers or weathered bedrock
- More drought-resistant than truly shallow wells
- More affordable than drilling 400-600 feet into solid bedrock
- Often appropriate for valley-floor properties in favorable areas
This approach works well in areas like Valley Center valley floors, portions of Ramona valley, and some agricultural valleys where water is available at moderate depths with good reliability.
Frequently Asked Questions
What is considered a shallow well?
Shallow wells are typically less than 50-75 feet deep, though some definitions extend to 100 feet. They tap unconfined surface aquifers rather than deep bedrock water sources. Most San Diego County residential wells are 200-500 feet deep—not shallow by industry standards.
Are shallow wells cheaper than deep wells?
Yes, when conditions allow. A 60-foot shallow well might cost $8,000-$15,000 vs. $25,000-$45,000 for a typical 300-500 foot deep well. However, most San Diego properties don't have sufficient groundwater at shallow depths, making deep wells necessary for reliability.
Can I have a shallow well in San Diego County?
It depends entirely on your property's location and geology. Valley areas with high water tables may support shallow wells, but most inland hillside and granite-dominant areas require deep drilling. A professional site assessment determines feasibility.
What are the disadvantages of shallow wells?
Shallow wells are more vulnerable to contamination, more affected by seasonal droughts, may have lower flow rates, can go dry during extended dry periods, and generally have shorter lifespans than properly drilled deep wells into bedrock aquifers.
Should I try shallow drilling first to save money?
No. Drilling a shallow well in unfavorable geology wastes money when it inevitably fails to produce adequate water. You'll then pay for deep drilling anyway, plus the cost of the failed shallow well. Proper assessment upfront prevents expensive mistakes.
How do I know if my property can support a shallow well?
A professional site assessment evaluating local geology, nearby well data, and water table conditions determines feasibility. We provide free assessments with honest recommendations about whether shallow drilling is realistic for your property.
Get An Honest Assessment for Your Property
We'll evaluate your property's geology, review nearby well data, and provide an honest assessment of whether shallow drilling is feasible—or whether deep drilling is necessary for reliable long-term water supply. No pressure, just straight answers.