Virginia county well guide

Well Water in Loudoun County, VA: Testing, Contractors and Rules

About 14,852 households in Loudoun County, 10% of the county, rely on a private well. Nobody tests that water unless the owner does.

Labs within 40 milesLicensed contractors
10%of households on a private well
Share on wells, county vs state
Loudoun County10%
Virginia average23%
0licensed contractors serve the county
<1 mito the nearest certified lab, Legacy Environmental Laboratory, LLC
Nostatewide test required when a home is sold

Roughly 10% of Loudoun County households, about 14,852, get their water from a private well rather than a utility. They are concentrated in the rural parts of the county, and they are on their own for testing.

Local rules for wells in Loudoun County

Private wells in Loudoun County follow Virginia's statewide rules, administered by Virginia Department of Health, Office of Environmental Health Services, through the local health departments. A water test is required when a new well is completed. There is no statewide test requirement when a home is sold, though lenders often ask for one. The cards below show the details and the official sources.

At a glance

Water test for a new wellRequired

Yes. A private well needs a construction permit from the local health department before drilling, must be built by a DPOR-licensed contractor with the Water Well/Pump specialty to the Private Well Regulations (grouted casing, setbacks of 50 ft from septic tanks and 100 ft from drainfields), and after completion the health department inspects it and requires a bacteriological sample that passes before the well is placed in service. The inspection statement is your record of the well.

Water test when a home is soldNot required statewide

No statewide requirement. The Residential Property Disclosure Act does not require a water test. FHA, VA and USDA loans normally require a bacteria, nitrate and lead sample from a certified lab before closing, and buyers can ask the local health department for the well's construction permit and inspection file.

What the state recommends

The Virginia Department of Health and the Virginia Household Water Quality Program recommend a coliform bacteria test every year and nitrate at least every three years, with a broader first test for hardness, iron, manganese, pH, sodium, copper, lead, arsenic and fluoride. Add radon and uranium in the Piedmont and Blue Ridge, sodium and chloride in Coastal Plain wells, and test again after flooding, well work or a change in taste, color or smell.

Free or low-cost testingAvailable

The Virginia Household Water Quality Program (Virginia Tech and Virginia Cooperative Extension) runs county drinking water clinics through the year: you pick up a kit from the Extension office, drop the sample back, and get results for 14 tests (bacteria, nitrate, metals, hardness, pH and more) with an interpretation meeting, for about $65, free in counties with grant funding. Local health departments and the VDACS regional animal health laboratories also run a bacteria test for a small fee.

Getting your water tested near Loudoun County

11 certified labs within 40 miles serve Loudoun County, starting with Legacy Environmental Laboratory, LLC in Sterling (in the county). Each card below shows whether the lab takes homeowner samples and which tests it is certified for.

7 certified labs within 40 miles

Licensed well contractors serving Loudoun County

No licensed contractor lists Loudoun County as a home base or service area yet. The finder below searches the whole state; most drillers travel several counties for a job.

Well depth and water chemistry

Wells in Loudoun County typically reach 100 to 300 ft in the Coastal Plain sands east of I-95; 200 to 500 ft in the fractured rock of the Piedmont; 150 to 400 ft in the limestone valleys of the Shenandoah and Valley and Ridge; 200 to 600 ft in the Blue Ridge and the southwest coalfields. What comes up with the water depends on the aquifer, and across Virginia the usual suspects are coliform bacteria (the most common failure statewide, worst in the piedmont and the valley), hardness (shenandoah valley and other limestone areas), iron and manganese (coastal plain and piedmont). A first full panel tells you which of them apply to your well.

Typical well depth

Varies by location. Check the state well record search for logs of nearby wells.

Contaminants to test for
  • Coliform bacteria (the most common failure statewide
  • Worst in the Piedmont and the Valley)
  • Hardness (Shenandoah Valley and other limestone areas)
  • Iron and manganese (Coastal Plain and Piedmont)
  • Corrosive low-pH water that pulls lead and copper from plumbing (Piedmont and Blue Ridge)
  • Radon and uranium (Piedmont granite)
  • Sodium
  • Chloride and fluoride (deep Coastal Plain wells)
  • Nitrate (Shenandoah Valley farm country
  • Eastern Shore)
  • Arsenic (locally in the Coastal Plain)
  • PFAS near airfields and military bases

Neighboring counties: City of Manassas Park, Fairfax County, City of Manassas, Prince William County.

What well work costs in Loudoun County

Basic bacteria and nitrate test$25 to $75lab fee, homeowner sample
Full panel lab test$150 to $400metals, VOCs, radiologicals
Well inspection$250 to $550flow, pressure, visual, water test
Submersible pump replacement$1,200 to $4,500parts and labor
Pressure tank replacement$400 to $1,200installed
Whole-house treatment system$800 to $6,000softener, iron filter, UV, RO
New well drilled$5,500 to $25,000about $25 to $65 per foot
Shock chlorination$80 to $300or about $20 as a DIY job

National ranges from published 2025 to 2026 contractor pricing. Local quotes vary with depth, access and materials.

Questions Loudoun County well owners ask

How many homes in Loudoun County are on a well?

About 14,852, or 10% of households, based on Census housing data and state well surveys. The share is highest outside the towns with public water.

Where is the closest certified lab to Loudoun County?

Legacy Environmental Laboratory, LLC in Sterling, inside the county. Call first to ask whether they accept homeowner samples.

Do I need a permit to drill a well in Loudoun County?

Yes. A private well needs a construction permit from the local health department before drilling, must be built by a DPOR-licensed contractor with the Water Well/Pump specialty to the Private Well Regulations (grouted casing, setbacks of 50 ft from septic tanks and 100 ft from drainfields), and after completion the health department inspects it and requires a bacteriological sample that passes before the well is placed in service. The inspection statement is your record of the well.

What does a well test cost near Loudoun County?

A bacteria and nitrate test runs $25 to $75 at most certified labs; a full panel with metals is $150 to $400. Mail-in kits cost about the same as walking in.