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Well Water Testing
water droplet on a pipette

Well Water Testing in Boulder County

Private Wells Should Be Tested Annually

The U.S. Environmental Protection Agency (EPA) recommends testing private wells annually. Without testing, the water quality is unknown, and it could be contaminated with naturally occurring or other contaminants.

Health Impacts of Water Contaminants

A variety of bacteria, parasites, and viruses can potentially cause Well Water Quality problems if humans ingest them. Testing water for each of these would be difficult and expensive. Instead, water testing for total coliform levels serves as an indicator of contamination.

Coliform bacteria can enter well water through various means, including sewage overflows, damaged or malfunctioning sewage systems, polluted stormwater runoff, and agricultural runoff. Private wells may become more vulnerable to such contamination after flooding or fires, particularly if they are shallow, have been dug or bored, or have been submerged by floodwater for long periods of time.

Water Testing Services

Water Testing Labs

Lab NameAddressCityPhone Number
Aerobiology Laboratory Associates780 Simms St.Golden866-620-9348
Analytica Environmental Labs12189 Pennsylvania St.Thornton303-469-8868
CDPHE - Lowry Campus8100 Lowry Blvd.Denver303-692-3048
CH Diagnostic & Consulting Service512 Fifth St.Berthoud970-532-2078
City of Fort Collins4316 Laporte Ave.Fort Collins970-221-6691
City of Golden1445 Tenth St..Golden303-384-8181
City of Northglenn2350 W. 112th Ave.Northglenn303-450-4074
Colorado Analytical Laboratory240 S. Main St.Brighton303-659-2313
Colorado Analytical Laboratory12860 W. Cedar Dr. Unit 101Lakewood303-659-2313
Colorado State University1250 East Dr.Fort Collins970-491-4837
GeoWater Services4091 Evergreen Pkwy.Evergreen303-670-3348
Gilpin County Public Health101 Norton Dr.Black Hawk303-582-5803
Industrial Laboratories4046 Youngfield St.Wheat Ridge303-287-9691
Murray-Brown Laboratories, LLC.4150 Jason St.Denver303-296-0264
Reservoirs Environmental, Inc.5801 Logan St.Denver303-964-1986
Stewart Environmental3801 Automation Way Suite #200Fort Collins970-226-5500
Stewart Environmental3801 Automation Way Suite #200Fort Collins970-226-5500
Town of Estes Park2455 Mary’s Lake Rd.Estes Park970-577-3624
Warren Analytical650 O St.Greeley970-475-0252
Weld County1555 N. 17th Ave.Greeley970-304-6415

Shock Chlorination

Well water can be contaminated with bacteria from many sources. The most common include repairing the pump or casing without follow-up chlorination, surface water entering the pump or casing, poor construction of the well, or leaks in the well or well casing.

Shock chlorination of a well may eliminate bacterial contamination, but well rehabilitation may be necessary if contamination continues to occur (as in a rusted or leaking casing). If you plan to shock chlorinate your well yourself, follow instructions carefully to ensure bacteria is eliminated.

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Contact Us

Water Quality Program

Main: 303-441-1564
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