By SCWS Team
Published February 1, 2026 · 14 min read
Sometimes the pump isn't the problem—the well is. Before you replace your third pump in five years, it's worth asking: is the well itself failing? Replacing pumps in a dying well is like putting new tires on a car with a broken transmission.
No one wants to hear that their well needs replacement. It's a major expense—often $15,000 to $50,000 or more in Southern California. But sometimes, a new well is the only viable solution. Understanding when your well is truly failing (not just the pump) and when rehabilitation won't work can save you from throwing money at a lost cause.
How Long Should a Well Last?
Before assuming the worst, understand that wells are built to last generations. A properly constructed water well should provide service for:
- Steel casing wells: 25-50 years (corrosion is the limiting factor)
- PVC/plastic casing wells: 50+ years (no corrosion)
- Bedrock wells: 50-100+ years (stable rock structure)
- Gravel-pack wells: 25-40 years (screen clogging over time)
The pump needs replacement every 10-15 years, but the well itself should far outlast the pump. If your well is having problems, the first step is determining whether it's the pump, the well, or the aquifer.
Pump Problem vs Well Problem
Pump problem: Pump won't start, cycles rapidly, no pressure
Well problem: Declining yield over years, sand/sediment, persistent contamination, structural damage visible on camera
Warning Signs Your Well Is Failing
These symptoms suggest problems with the well itself—not just the pump:
1. Declining Water Yield That Doesn't Recover
All wells experience some fluctuation based on rainfall and seasonal conditions. But if your well's yield has steadily declined over months or years—and doesn't recover even after wet seasons—something fundamental has changed:
- Aquifer depletion: The water source itself is diminishing
- Screen clogging: Mineral buildup blocking water entry
- Bio-fouling: Iron bacteria plugging the well
- Formation collapse: Sediment filling the well bottom
A flow test compared to the well's original yield tells the story. If you're getting 2 GPM from a well that once produced 10 GPM, there's a significant problem.
2. Well Runs Dry Despite Adequate Water Table
If neighboring wells are fine but yours runs dry, the problem is your well specifically—not a regional drought. This could mean:
- Clogged screens preventing water from entering
- Casing damage allowing the well to drain
- Pump set in a zone that's no longer producing
- Well wasn't drilled deep enough originally
3. Increasing Sand and Sediment
Sand or sediment in your water—especially if it's getting worse over time—indicates structural failure:
- Failed well screen: Holes or corrosion letting sand through
- Casing corrosion: Holes in the casing allowing surface contamination
- Gravel pack failure: Filter media washed away
- Formation collapse: Unstable geology caving into the well
Sand damages pumps, clogs pipes, and indicates serious well problems. While some issues can be repaired, severe structural damage often means the well is beyond saving.
4. Persistent Contamination
If your well tests positive for bacteria, nitrates, or other contaminants repeatedly—and treatment or disinfection provides only temporary relief—the contamination source may be:
- Compromised well seal: Surface water entering around the casing
- Casing holes: Allowing contaminated shallow water to enter
- Poor original construction: Inadequate sealing or depth
- Nearby contamination source: Septic system, feedlot, etc.
Some contamination can be addressed by repairing the well seal or casing. But if the well was poorly constructed from the start, or if contamination is entering below the water table, a new well drilled to a deeper, cleaner aquifer may be the only solution.
5. Changes in Water Taste, Smell, or Appearance
Sudden or progressive changes in water quality indicate something has shifted:
- Sulfur smell: Hydrogen sulfide—may indicate bacteria or changing water sources
- Iron staining: Increasing iron may mean drawing from different strata
- Salty taste: Possible saltwater intrusion or cross-contamination
- Chemical taste: Could indicate surface contamination entering
6. Repeated Pump Failures
If you're replacing pumps every few years instead of every 10-15 years, your well is damaging the pumps:
- Sand and sediment destroying impellers
- Corrosive water attacking pump components
- Low water causing pumps to run dry and burn out
- Unstable formations causing pump jamming
Replacing pumps treats the symptom, not the cause. If your well is eating pumps, address the underlying well problem—or replace the well.
7. Visible Casing Damage
A well video inspection can reveal:
- Holes in the casing: Corrosion has eaten through
- Casing separation: Joints have pulled apart
- Collapsed casing: Sections have caved in
- Heavy encrustation: Mineral buildup blocking the well
- Damaged screen: Broken or corroded intake area
Some casing damage can be repaired with liners or sleeves. But extensive damage—especially collapse—often means the well is finished.
When Rehabilitation Won't Work
Well rehabilitation—cleaning, treating, or repairing an existing well—can often restore lost production. Common techniques include:
- Chemical treatment: Dissolving mineral scale and bio-fouling
- Hydrofracturing: High-pressure water to open fractures
- Mechanical cleaning: Brushing and jetting screens
- Acidizing: Dissolving calcium and iron deposits
- Casing repair: Liners and patches for damaged areas
However, rehabilitation has limits. It will NOT work when:
The Aquifer Is Depleted
If the water source itself has been exhausted—either regionally or in your well's zone—no amount of cleaning will bring water back. You need to tap a different aquifer, which means a new (usually deeper) well.
Casing Is Severely Damaged
Minor holes can sometimes be patched with liners. But if the casing has:
- Multiple sections of severe corrosion
- Collapse or major deformation
- Holes throughout its length
- Failed seals allowing surface contamination
The well cannot be made sanitary or structurally sound. A new well is required.
Contamination Can't Be Eliminated
If contamination is entering the well at depth—not through surface seal problems—rehabilitation can't fix it. This includes:
- Naturally occurring arsenic, uranium, or other contaminants
- Saltwater intrusion from over-pumping coastal aquifers
- Cross-contamination between aquifer layers
- Nearby pollution that's reached the water table
Construction Doesn't Meet Standards
Older wells may have been built without proper sealing, at insufficient depth, or with materials that have failed. If the well's fundamental construction is inadequate, no repair can bring it up to safe, functional standards.
Previous Rehabilitation Failed
If you've already tried rehabilitation and the improvement was temporary or insufficient, the underlying problems are beyond what cleaning can solve.
Your Options: New Well vs. Deepening vs. Hydrofracturing
Before committing to a new well, understand all your options:
Option 1: Well Rehabilitation ($3,000-$15,000)
Best for: Wells with clogged screens, bio-fouling, or mineral encrustation where the structure is sound.
- Pros: Lowest cost, preserves existing infrastructure
- Cons: May provide only temporary improvement, doesn't address structural damage
- Success rate: 60-80% for appropriate candidates
Option 2: Hydrofracturing ($5,000-$15,000)
Best for: Bedrock wells with low yield where opening fractures might increase flow.
- Pros: Can significantly increase yield in the right geology
- Cons: Only works in fractured rock, results not guaranteed
- Success rate: 70-80% see improvement; 50-60% see significant improvement
Option 3: Well Deepening ($10,000-$30,000)
Best for: Wells where the existing casing is sound but the current depth doesn't reach adequate water.
- Pros: Preserves existing well, may reach better aquifer
- Cons: Limited by existing casing condition, may not find water
- Success rate: Depends heavily on local geology—requires hydrogeological evaluation
Option 4: New Well ($15,000-$50,000+)
Best for: Failed wells, contamination issues, or when significantly more water is needed.
- Pros: Fresh start with modern construction, can choose optimal location and depth
- Cons: Highest cost, requires permits, may still have uncertainty about yield
- Success rate: 90%+ with proper site evaluation
Decision Framework
Choose rehabilitation if: Well is structurally sound, problem is clearly clogging/fouling
Choose hydrofracturing if: Bedrock well with fractured geology, yield is primary issue
Choose deepening if: Casing is good, known deeper water available
Choose new well if: Multiple structural problems, contamination, or rehabilitation has failed
Cost Comparison
When comparing options, consider total cost of ownership—not just upfront expense:
| Option | Upfront Cost | Expected Duration | 10-Year Cost |
|---|---|---|---|
| Rehabilitation | $5,000-$10,000 | 3-10 years | $10,000-$20,000* |
| Hydrofracturing | $8,000-$15,000 | 10-20+ years | $8,000-$15,000 |
| Deepening | $15,000-$30,000 | 20-30+ years | $15,000-$30,000 |
| New Well | $25,000-$50,000 | 30-50+ years | $25,000-$50,000 |
*May need repeat rehabilitation
The Evaluation Process
Don't guess—get a professional evaluation before committing to expensive work:
Step 1: Flow Test
Measure the well's current yield and compare to original records (if available). This establishes how much capacity has been lost.
Step 2: Video Inspection
A downhole camera reveals casing condition, screen status, sediment accumulation, and structural problems. This is essential information for making the repair-vs-replace decision.
Step 3: Water Quality Testing
Comprehensive testing identifies contamination issues and their likely sources.
Step 4: Hydrogeological Assessment
For new well or deepening decisions, understanding local geology predicts what you'll find at different depths.
If You Need a New Well
If evaluation confirms a new well is needed, here's what to expect:
Permitting
California requires permits for new wells. In San Diego County, this involves county environmental health, and possibly the watermaster if you're in an adjudicated basin. Budget 2-4 weeks for permitting.
Site Selection
The new well may or may not be in the same location as the old one. Site selection considers:
- Required setbacks from septic, property lines, buildings
- Access for drilling equipment
- Geology and expected water depth
- Distance to the house (affects pressure and costs)
Old Well Abandonment
California law requires proper abandonment of unused wells to prevent groundwater contamination. The old well must be sealed—you can't just leave it. This adds $2,000-$5,000 to the project cost but is legally required.
Timeline
From decision to flowing water:
- Permitting: 2-4 weeks
- Drilling: 1-3 days
- Development and testing: 1-2 days
- Pump installation: 1 day
- Connection to house: 1-2 days
Total: 3-6 weeks depending on permitting and contractor availability.
Frequently Asked Questions
How long do water wells last?
A properly constructed water well typically lasts 30-50 years, though many wells remain productive for much longer. The lifespan depends on aquifer conditions, water quality, well construction, and maintenance. Wells in sandy aquifers may experience screen clogging earlier. Wells tapping stable bedrock aquifers often last 50+ years. The pump will need replacement every 10-15 years regardless of well condition.
When is a new well better than rehabilitation?
A new well is typically better than rehabilitation when: the aquifer itself is depleted (not just the well), casing is severely corroded or collapsed, contamination sources cannot be eliminated, well construction doesn't meet current codes, rehabilitation costs exceed 40-50% of new well cost, or the well has failed rehabilitation attempts before. A new well also makes sense when you need significantly more water than the current well can provide.
How much does it cost to drill a new well vs rehabilitate an old one?
In Southern California, a new residential well typically costs $15,000-$50,000+ depending on depth (often 300-600+ feet). Well rehabilitation costs $3,000-$15,000 depending on the problems and methods used. However, rehabilitation may only provide temporary improvement, while a new well provides decades of service. Compare total cost of ownership, not just upfront cost.
What are the signs my well is failing?
Key warning signs include: declining water yield that doesn't recover, pump running dry despite adequate water table, increasing sediment or sand in water, persistent water quality problems (contamination that keeps returning), changes in water taste or odor, and need for progressively more pump replacements. A well inspection with video camera can reveal structural problems like casing damage or screen failure.
Can a dry well recover?
It depends on why the well went dry. If the aquifer temporarily dropped during drought, the well may recover when water tables rebound. However, if the aquifer is permanently depleted, the well won't recover on its own. If the well structure has failed (clogged screens, collapsed casing), the well may need rehabilitation or replacement even if water is present. A professional evaluation can determine if recovery is possible.
Worried About Your Well?
If your well is showing warning signs, get a professional evaluation before making expensive decisions. We provide honest assessments of repair vs. replace options for wells throughout San Diego and Riverside Counties.