RC
Rock County Health Department Janesville
3328 US Highway 51 N, Janesville, WI
Water testing labs in Rock County, WI
3 state-accredited water testing labs in Rock County, WI.
3 certified labsUpdated October 2026Source: state lab accreditation records
Source: Wisconsin DNR list of labs certified for coliform bacteria testing, list dated Oct 28, 2026. Find a Water Test is independent and not affiliated with the Wisconsin Department of Natural Resources. Certification covers specific tests, so confirm the lab is certified for the ones you need: Verify a certification.
3 certified labs near Rock County, WI
BW
Beloit Water Pollution Control Facility
555 Willowbrook Rd, Beloit, WI
Public water system lab. Many don't accept private well samples, so call first.
JW
Janesville Wastewater Lab
3300 Tripp Rd, Janesville, WI
Public water system lab. Many don't accept private well samples, so call first.
Mail-in labs that ship to Rock County, WI
How mail-in testing worksNT
National Testing Laboratories (WaterCheck)
Ships nationwide
Single tests from $75; well and city packages $165 to $440
Certified in Wisconsin
TS
Tap Score by SimpleLab
Ships nationwide
Single-contaminant kits from about $145; full well and city panels about $300 to $870
Testing service: sends your sample to a partner lab.
Bad result? Get help from water treatment pros near Rock County, WI
Tell us what your test found and we'll connect you with up to three local water treatment companies.
What happens next
- We match your ZIP to water treatment companies nearby.
- They contact you directly to talk through your results.
- Compare options and pick one, or none. No fee, no obligation.
Free, no obligation. We don't sell your details to anyone else.
Just need a lab? Every certified lab is listed above with directions.
Run one of these businesses? Claim your listing, add a missing one or get featured in Rock County, WI.
Well water guides
Common questions
Where can I test well water near Rock County, WI?
The state-accredited labs above serve Rock County, WI. Many offer sample bottles you collect at home.
What should I test for near Rock County, WI?
Start with total coliform bacteria and nitrates, then ask your county health department about local concerns.