Colorado Well Finder › Wells by county › Boulder County
A Boulder County well budget starts with the ground under the lot, not the county average. Fractured mountain bedrock can produce very different results on neighboring properties, and countywide records also include alluvial and Denver Basin wells.
Colorado DWR records contain 20,340 permitted wells in Boulder County, with 12,668 recorded as constructed. The reported median depth is 154 feet and median yield is 7.0 gpm. Those are useful starting points, but a purchase decision needs nearby construction records, a current pumping test and a permit that supports your intended use.
Figures are computed from Colorado Division of Water Resources permit records for all permitted wells in the county. Not every permit reports every field; each statistic uses the wells that report it.
| Depth statistic | Feet |
|---|---|
| 25th percentile | 30 |
| Median | 154 |
| 75th percentile | 320 |
| 90th percentile | 500 |
| Deepest on record | 4,550 |
| Aquifer named on permits | Wells |
|---|---|
| unnamed / fractured-bedrock aquifer | 17,994 |
| Alluvial | 458 |
| Laramie Fox Hills | 220 |
| Yield statistic | gpm |
|---|---|
| 25th percentile | 5.0 |
| Median | 7.0 |
| 75th percentile | 10.0 |
| Median depth to water | 20 ft |
| Median water level by decade | Depth to water |
|---|---|
| 1950s | 17 ft |
| 1960s | 20 ft |
| 1970s | 25 ft |
| 1980s | 40 ft |
| 1990s | 68 ft |
| 2000s | 11 ft |
| 2010s | 45 ft |
| 2020s | 14 ft |
Among the 13,297 wells reporting depth, the median is 154 feet, but the middle half spans 30-320 feet. That is a wide bidding range: a median-depth estimate should not become a fixed budget for an untested lot. The 90th-percentile depth is 500 feet.
Permits identify 17,994 wells as unnamed or fractured-bedrock aquifer, alongside 458 Alluvial wells and 220 Laramie Fox Hills wells. In granite and gneiss, usable water depends on intersecting productive fractures, not simply reaching a standard depth. For property in Pine Brook Hill, Seven Hills or Tall Timber, compare nearby logs with similar terrain and geology before deciding which county figures apply.
The 3,889 wells reporting pump yield have a 7.0 gpm median, with the middle half at 5.0-10.0 gpm. Reported yields of 5-15 gpm account for 69% of that group. Those results can support ordinary household demand when sustained, but an old completion-record yield is not a current performance guarantee.
The low end deserves attention: 3% report under 1 gpm. A buyer considering one of those wells should investigate recovery, usable storage and peak household demand before closing. Fractured-bedrock production can differ sharply between nearby holes. Ask for a pumping and recovery test rather than judging supply from pressure at a faucet or the size of the installed pump.
Only 672 records report a static water level. Their median depth to standing water is 20 feet below ground, with the middle half at 9-70 feet. Static level describes where water rests in the well when it is not being pumped; it is not total well depth or proof of a strong supply.
The decade medians do not show a steady countywide decline. They move from 17 feet in the 1950s to 68 feet in the 1990s, then 11 feet in the 2000s, 45 feet in the 2010s and 14 feet in the 2020s. Different wells and measurement conditions can affect those comparisons. Evaluate repeated measurements from the property itself before drawing a trend conclusion.
Permit activity includes 3,229 issuances in the 1970s and 3,425 in the 1990s, compared with 1,617 in the 2010s. The 2020s have 1,281 permits so far, and the newest permit year is 2026. The current decade is incomplete, and permit totals should not be read as completed-well counts.
Leading driller entries include Ground Water Systems Inc (Wilson, Richard R.) with 2,452 records and Ingram Drilling Inc. (Ingram, Stephen E.) with 1,053. Another prominent entry, Authorized (Pe, Pg), has 2,322; treat that as a record label, not a verified drilling-company recommendation. Domestic/household use accounts for 67% of permits, while monitoring accounts for 19%, so not every mapped well is a household supply comparison.
The supplied fractured-granite and gneiss cost model uses $65-$100 per foot. At the 154-foot median depth, that puts the drilled hole at about $10,000-$15,400. A finished well with pump, tank, trenching and electrical is modeled at $16,000-$27,400.
Use that as a planning allowance, not a parcel quote. The 30-320-foot middle-half depth range leaves substantial room for a different final bill. Ask bidders to identify casing and grout allowances, access requirements, pump selection and what happens if drilling must continue deeper. Confirm that the proposed price covers the route from the well to the house, not just work at the borehole. Ground conditions outside the mountain-bedrock setting may require a different estimate.
The environmental mapping includes 490 PFAS sampling/contamination sites, 949 historic mine features and 88 EPA Superfund/cleanup sites within about 10 miles. These are screening flags, not evidence that a particular Boulder County well is contaminated. A sampling location is not automatically a confirmed contamination source.
Review the locations and available findings around the parcel, then arrange laboratory testing appropriate to its setting, including bacteria and chemistry. Inspect casing, grout and drainage at the wellhead. The records do not establish the chance of a dry hole on your lot. Low yield, poor water quality and drilling failure are separate risks, and a successful neighbor does not eliminate any of them.
Start with the exact parcel and its DWR permit. Confirm authorized uses rather than assuming a domestic well allows irrigation, livestock or another residence. Exempt household-use permits can be restrictive, and proposed uses in over-appropriated basins may require an augmentation plan.
For an existing home, match the permit, construction log and pumping equipment to the property. For vacant land in Tall Timber, Gunbarrel or Eldorado Springs, review neighboring wells and lay out drilling access, the house, utilities and septic area together. Verify required well-to-septic separation and county approvals before fixing the building footprint. Make satisfactory water testing, supply evaluation and permit review part of the purchase process, not work postponed until excavation starts.
| Decade permitted | Wells |
|---|---|
| 1950s | 423 |
| 1960s | 795 |
| 1970s | 3,229 |
| 1980s | 2,355 |
| 1990s | 3,425 |
| 2000s | 2,014 |
| 2010s | 1,617 |
| 2020s | 1,281 |
| Most active drillers on record | Wells |
|---|---|
| Ground Water Systems Inc (Wilson, Richard R.) | 2,452 |
| Authorized (Pe, Pg) | 2,322 |
| Ingram Drilling Inc. (Ingram, Stephen E.) | 1,053 |
How this is built: the median permitted depth here times the per-foot range for this ground, plus the normal system costs. A lot at the 75th-percentile depth (320 ft) would run roughly $26,800–$44,000. See the full Colorado well cost guide.
Counts come from EPA, USGS and state datasets layered on the Colorado Well Finder map. A count is not a verdict on any one well; it tells you what to test for.
The numbers above are the area average. Your lot is one point on the map. Search the address to see the real depth, yield and aquifer of each permitted well around it.
Map wells near Boulder CountyFor a Boulder County lot, Tri-Lakes Contracting is a licensed Colorado contractor for access driveways, site development, new-build septic systems and custom homes. Coordinate the well location with access, septic and the building footprint before excavation begins.
Licensed Colorado custom home builder · licensed driveway & excavation contractor · licensed septic installer
A listing photo can't tell you whether a lot is a dream or a money pit. Two parcels near Boulder County can carry the same asking price while one needs an $80,000 driveway and a $45,000 engineered septic the other doesn't. The well numbers on this page are the start of that answer. A Tri-Lakes Site Feasibility Report is the rest of it: a licensed general contractor, excavator and septic installer reads the parcel the way we would if we were about to build on it, and puts the real cost in writing before your money is committed.
Spend a little to know. Or gamble a lot to guess. Realtors sell the view and inspectors look at houses that already exist. We're the people who'd build it, so we catch what quietly turns a "great deal" into a budget disaster: bad access, buried rock, steep grade, soil that won't pass for a normal septic, water that's a fortune to reach. And if the lot is good, you've already got a builder ready to do the work, driveway to drywall.
Under contract, comparing parcels, or a realtor with a rural listing whose buyers keep asking "what will it cost to build here?" This is the due-diligence step almost everyone skips, and the one that saves the most.
Driveway, site work, septic or a build near Boulder County. Licensed GC, excavator and septic installer.
Got it. Tri-Lakes will get back to you shortly.
Something went wrong sending that. Email kyle@trilakes.co instead.
The median reported depth is 154 feet, and the middle half of wells falls between 30 and 320 feet. The 90th-percentile depth is 500 feet. These figures cover all permitted-well settings in the county, so compare nearby construction logs and geology before using the median to budget a mountain property.
The mountain-bedrock model uses $65-$100 per foot. At the 154-foot median depth, the drilled hole is about $10,000-$15,400, while a finished well with pump, tank, trenching and electrical is about $16,000-$27,400. Actual bids need parcel-specific depth assumptions, access details and clear allowances for casing, grout and additional drilling.
Among wells reporting pump yield, the median is 7.0 gpm and the middle half is 5.0-10.0 gpm. Under 1 gpm accounts for 3% of reports. A recorded yield describes a past test, not guaranteed current production. Before buying, have the well's sustained output and recovery evaluated against household demand.
Safety has to be established for the individual well through laboratory testing. Nearby environmental mapping includes 490 PFAS sampling/contamination sites, 949 historic mine features and 88 EPA Superfund/cleanup sites within about 10 miles. Those counts do not establish contamination at your property. Use local site findings, well condition and laboratory results to guide treatment decisions.
The available decade medians do not show a consistent countywide drop. Median static depth was 68 feet in the 1990s, 11 feet in the 2000s, 45 feet in the 2010s and 14 feet in the 2020s. Only 672 records report static levels, and comparisons involve different wells. Repeated measurements at the same property are more useful.
Driveway, septic, site development, feasibility or a custom build near Boulder County.
Shopping a lot? Run the $99 instant buildability check →