# WaterListed

> Directory of U.S. state-certified drinking-water laboratories for private-well owners, built only from official lists (state lab certification lists; Wyoming's from U.S. EPA Region 8). 3361 listings (2291 distinct labs after linking the same business across state lists) from 45 states, compiled 2026-11-15. Pennsylvania data comes from June 2024 reports and is marked stale; New York covers only the PFAS-rebate table.

Certification fields (lab name, state ID, analytes/groups, expiry, homeowner-sample flag) are copied from each state's list; unknown fields are empty. Contaminant levels: certified = named on the list; group = certified for a parent analyte group; partial = list marks group as partial; subcontracted = lab sends to another accredited lab. Business-level details only. Not an endorsement; confirm with the lab.

## States
- [Connecticut](https://waterlisted.com/states/ct/): 17 listings; source: https://portal.ct.gov/dph/-/media/dph/dph-2025/environmental-lab-certification/lab-lists/in-state-laboratories-certified-to-test-drinking-water_20261009.pdf (10/09/2026)
- [Minnesota](https://waterlisted.com/states/mn/): 23 listings; source: https://www.health.state.mn.us/communities/environment/water/docs/wells/waterquality/labmap.pdf (October 2026)
- [Vermont](https://waterlisted.com/states/vt/): 46 listings; source: https://www.healthvermont.gov/sites/default/files/documents/pdf/PHL_DW-Certified-Labs.pdf (September 28, 2026)
- [Maine](https://waterlisted.com/states/me/): 12 listings; source: https://www.maine.gov/dhhs/mecdc/sites/maine.gov.dhhs.mecdc/files/CommercialListMaineLabs.pdf (Last updated 5/16/2026)
- [Ohio](https://waterlisted.com/states/oh/): 75 listings; source: https://dam.assets.ohio.gov/image/upload/epa.ohio.gov/Portals/28/documents/labcert/Combined-Lab-List.pdf (November 2026)
- [Wisconsin](https://waterlisted.com/states/wi/): 135 listings; source: https://apps.dnr.wi.gov/dwsportalpub/BactiLab (live page)
- [Virginia](https://waterlisted.com/states/va/): 146 listings; source: https://dgs.virginia.gov/division-of-consolidated-laboratory-services/certification-accreditation/find-a-lab (Current as of 8/1/2026)
- [Washington](https://waterlisted.com/states/wa/): 91 listings; source: https://apps.ecology.wa.gov/laboratorysearch/appfiles/DWLabsScopesInternet.pdf (Information current as of 11/13/2026)
- [Pennsylvania](https://waterlisted.com/states/pa/): 169 listings; source: https://files.dep.state.pa.us/Water/BSDW/DrinkingWaterManagement/PrivateWaterWells/DW_Lab_Certification_06-11-2024%20Lab%20Accreditation%20Report.pdf (STALE - report dated 6/11/2024)
- [New York](https://waterlisted.com/states/ny/): 39 listings; source: https://www.health.ny.gov/environmental/water/drinking/privatewellspilot/labs.htm (page fetched 2026-10-29)
- [Massachusetts](https://waterlisted.com/states/ma/): 36 listings; source: https://www.mass.gov/doc/massdep-certified-laboratories-offering-analytical-services-for-private-well-owners-and-residential-customers/download (Created and published on 12/18/2025)
- [California](https://waterlisted.com/states/ca/): 304 listings; source: https://www.waterboards.ca.gov/drinking_water/certlic/labs/ (Map layer fetched 2026-11-15; scope PDF as of 6/8/2026)
- [Missouri](https://waterlisted.com/states/mo/): 89 listings; source: https://dnr.mo.gov/water/business-industry-other-entities/technical-assistance-guidance/public-drinking-water-systems/chemical-labs/excel (Live export fetched 2026-11-15 (no list date printed in the file))
- [Tennessee](https://waterlisted.com/states/tn/): 150 listings; source: https://www.tn.gov/content/dam/tn/environment/water/drinking-water-unit/wr_wq_dw_certified-commercial-labs.pdf (10/2/2026 (page footers 10/06/2026); As of October 2, 2026 (PDF title; page footers 10/06/2026))
- [Georgia](https://waterlisted.com/states/ga/): 43 listings; source: https://epd.georgia.gov/media/134841/download (January 9, 2025)
- [Alabama](https://waterlisted.com/states/al/): 64 listings; source: https://adem.alabama.gov/sites/default/files/2026-04/BacteriologicalLabs.pdf (Revised: April 7, 2026)
- [Michigan](https://waterlisted.com/states/mi/): 212 listings; source: https://www.michigan.gov/egle/-/media/Project/Websites/egle/Documents/Programs/RRD/Lab/Chemistry-Laboratories.pdf (SOM Certified Labs - Chemistry 3/11/2026 (chemistry, microbiological, lead and copper lists); 9/8/2025 (radiological, in-state PFAS lists))
- [Illinois](https://waterlisted.com/states/il/): 96 listings; source: https://epa.illinois.gov/content/dam/soi/en/web/epa/topics/certification-training/lab-accreditation/documents/Primary-Secondary-Labs-Chemical-12092025.pdf (12/09/2025 (date in the file name; the PDF prints no date); TNI LAMS as fetched 2026-11-15)
- [Iowa](https://waterlisted.com/states/ia/): 58 listings; source: https://programs.iowadnr.gov/labcert/Excel/ExportToExcelCertifiedLabs (Date Generated: 11/14/2026 (LabCert, live database))
- [Florida](https://waterlisted.com/states/fl/): 222 listings; source: https://www.floridahealth.gov/licensing-regulations/regulated-facilities/environmental-laboratories/ (DOH Version: 11/07/2026 08:30:01 (Qlik app refresh 11/9/2026 4:26:47 AM; live database))
- [Texas](https://waterlisted.com/states/tx/): 144 listings; source: https://www.tceq.texas.gov/agency/qa/env_lab_accreditation.html (Live database, searched 2026-11-15 ("accurate as of the date and time of the search"))
- [Louisiana](https://waterlisted.com/states/la/): 49 listings; source: https://ldh-oph.qualtraxcloud.com/ShowDocument.aspx?ID=2668 (Current as of 2/12/2026)
- [Oklahoma](https://waterlisted.com/states/ok/): 31 listings; source: https://oklahoma.gov/deq/divisions/state-environmental-laboratory-services/laboratory-accreditation.html (Live database, searched 2026-11-02)
- [Nevada](https://waterlisted.com/states/nv/): 58 listings; source: https://ndep.nv.gov/water/lab-certification/ (Live database, searched 2026-11-15 ("accurate as of the date and time of the search"))
- [Wyoming](https://waterlisted.com/states/wy/): 12 listings; source: https://www.epa.gov/system/files/documents/2026-02/20260211_wy_r8ic_lablist.pdf (Current as of February 2026 (page footer 2/17/2026))
- [Hawaii](https://waterlisted.com/states/hi/): 19 listings; source: https://health.hawaii.gov/statelab/files/2026/03/sld-hm-certified-labs-chem.pdf (August 12th, 2026)
- [Mississippi](https://waterlisted.com/states/ms/): 5 listings; source: https://msdh.ms.gov/safe-food-water-and-housing/water-supply/private-well-water-testing/water-supply-certification-labs (undated page; MSDH site data shows it updated Oct 10, 2026)
- [South Dakota](https://waterlisted.com/states/sd/): 16 listings; source: https://danr.sd.gov/OfficeOfWater/DrinkingWater/LaboratoryCert.aspx (undated (the page shows only 'Copyright © 2026'))
- [Colorado](https://waterlisted.com/states/co/): 94 listings; source: https://datastudio.google.com/embed/u/0/reporting/18DpQAMm-riBo5DfqEUCgDqMspPPhu-Ul/page/ZkmVB (Live report, no edit date shown; data read by the report at 2026-11-02 20:39 UTC (Looker Studio dataTimestamp))
- [Kansas](https://waterlisted.com/states/ks/): 47 listings; source: https://www.kdhe.ks.gov/1117/Environmental-Laboratory-Accreditation-P (Live database, searched 2026-11-15 ("believed to be accurate at the time of the search"))
- [Maryland](https://waterlisted.com/states/md/): 92 listings; source: https://mde.maryland.gov/programs/water/water_supply/Documents/Maryland-Certified-DW-Labs.pdf (Latest Revisions: 10/1/2026)
- [West Virginia](https://waterlisted.com/states/wv/): 50 listings; source: https://dhhr.wv.gov/ols/labs/Documents/Environmental%20Chemistry/waterqualitylabs%20%282026%29%20-%20Updated%20List%20%288-20-26%29.pdf (printed Thursday, August 20, 2026)
- [North Carolina](https://waterlisted.com/states/nc/): 238 listings; source: https://slphreporting.dph.ncdhhs.gov/Certification/CertifiedLaboratory.asp?SubTopic=ShowDWLabs&LabType=Commercial (generated on request (no date printed), fetched 2026-11-07)
- [Arizona](https://waterlisted.com/states/az/): 51 listings; source: https://ells-lab-search.azdhs.gov/DrinkingWaterTestingLabs/drinkingwatersearchcontentpage (current as of Saturday, November 7, 2026)
- [Montana](https://waterlisted.com/states/mt/): 36 listings; source: https://dphhs.mt.gov/publichealth/laboratoryservices/waterlaboratorycertificationprogram (page as fetched 2026-11-15 (no date printed))
- [Alaska](https://waterlisted.com/states/ak/): 26 listings; source: https://dec.alaska.gov/eh/lab/micro-lab-cert-status (page as fetched 2026-11-03 (no date printed); chemistry page not available)
- [Puerto Rico](https://waterlisted.com/states/pr/): 12 listings; source: https://www.salud.pr.gov/CMS/DOWNLOAD/9940 (Revisado agosto 2025)
- [Oregon](https://waterlisted.com/states/or/): 92 listings; source: https://www.oregon.gov/OHA/PH/LaboratoryServices/EnvironmentalLaboratoryAccreditation/Pages/DrinkingWaterTesting.aspx (search as fetched 2026-11-15 (live database, no list date))
- [Indiana](https://waterlisted.com/states/in/): 74 listings; source: https://www.in.gov/health/laboratories/drinking-water-laboratory-certification/ (layer data edited 2026-08-17)
- [Rhode Island](https://waterlisted.com/states/ri/): 43 listings; source: https://health.ri.gov/sites/g/files/xkgbur1006/files/2025-02/EurofinsEnvTest.pdf (page as fetched 2026-11-07 (no date printed); certificate appendix issued 1/21/2026)
- [Nebraska](https://waterlisted.com/states/ne/): 5 listings; source: https://dhhs.ne.gov/Public%20Health%20Lab%20Documents/certified%20labs.pdf (no date printed; PDF created 2024-05-22 (file metadata))
- [Kentucky](https://waterlisted.com/states/ky/): 14 listings; source: https://eec.ky.gov/Environmental-Protection/Water/Protection/Documents/KYCertifiedDWPFASLabList.pdf (Revised 1/23/2026)
- [South Carolina](https://waterlisted.com/states/sc/): 49 listings; source: https://www.des.sc.gov/programs/bureau-regional-laboratory-services/environmental-laboratory-certification/commercial-environmental-laboratory-mapping-celmapp (no date printed; CELMAPP data last refreshed 2026-10-10 (LastRefreshDate of SCDES's details table))
- [New Mexico](https://waterlisted.com/states/nm/): 44 listings; source: https://service.web.env.nm.gov/urls/wemUzxnK (Last Updated: 10/26/2026)
- [Idaho](https://waterlisted.com/states/id/): 33 listings; source: https://publicdocuments.dhw.idaho.gov/WebLink/ElectronicFile.aspx?docid=36255&dbid=0&repo=PUBLIC-DOCUMENTS (2026 EPA Region 10 Drinking Water Certificate Microbiology LT2: letter of January 22, 2026; 2025 EPA Region 10 Drinking Water Certificate Chemistry: letter of March 24, 2025; 2025 EPA Region 10 Drinking Water Certificate Microbiology: letter of May 23, 2025)

## Explainers
- [Nitrate](https://waterlisted.com/learn/nitrate/)
- [Coliform bacteria / E. coli](https://waterlisted.com/learn/coliform-bacteria/)
- [Arsenic](https://waterlisted.com/learn/arsenic/)
- [Lead](https://waterlisted.com/learn/lead/)
- [PFAS](https://waterlisted.com/learn/pfas/)
- [Uranium](https://waterlisted.com/learn/uranium/)
- [Radon](https://waterlisted.com/learn/radon/)
- [Manganese](https://waterlisted.com/learn/manganese/)
- [VOCs](https://waterlisted.com/learn/vocs/)

## Guides
- [Arsenic removal from well water: match the filter to the arsenic form](https://waterlisted.com/guides/arsenic-removal-well-water/)
- [Artesian well: what it is, and is its water safer to drink?](https://waterlisted.com/guides/artesian-well/)
- [How to collect a well water sample: bacteria, first-draw lead, radon and more](https://waterlisted.com/guides/collect-well-water-sample/)
- [Well and septic records: how to find your well log and septic permit, and what they tell you to test](https://waterlisted.com/guides/find-well-septic-records/)
- [Fracking and well water contamination: what EPA found, and the baseline test to get before drilling nearby](https://waterlisted.com/guides/fracking-well-water-testing/)
- [Free well water testing: which states and counties pay for your test](https://waterlisted.com/guides/free-well-water-testing/)
- [Hard water in well water: how to test it, read the number and decide whether to soften](https://waterlisted.com/guides/hard-water-well/)
- [How a private well works: from the aquifer to your tap, and what your well's design means for testing](https://waterlisted.com/guides/how-a-private-well-works/)
- [How often to test well water, and 9 events that call for an extra test](https://waterlisted.com/guides/how-often-to-test-well-water/)
- [Testing a well: what to order, how to take each sample, how to read the report](https://waterlisted.com/guides/how-to-test-well-water/)
- [Iron Bacteria in Well Water: Signs, Tests and Why Treatment Has to Be Repeated](https://waterlisted.com/guides/iron-bacteria-well-water/)
- [Iron in well water: what the test result means and which treatment fits](https://waterlisted.com/guides/iron-in-well-water/)
- [Is well water safe to drink? What the national data show, and how to know for your well](https://waterlisted.com/guides/is-well-water-safe-to-drink/)
- [Drilled well cost: what official sources say, and the first test a new well needs](https://waterlisted.com/guides/new-well-cost-first-test/)
- [Old water well on your property: test it, restore it or seal it](https://waterlisted.com/guides/old-water-well/)
- [pH and TDS in well water: how to test them, read the numbers and know what to test next](https://waterlisted.com/guides/ph-tds-well-water/)
- [Radon in water mitigation: aeration or carbon by test result, cost and retest](https://waterlisted.com/guides/radon-in-water-mitigation/)
- [How to read a well water test report, line by line](https://waterlisted.com/guides/read-well-water-test-report/)
- [How to remove nitrate from well water: what works, what doesn't, and the sulfate catch](https://waterlisted.com/guides/remove-nitrate-from-well-water/)
- [How to remove sulfur smell from well water: find the source, test, then treat](https://waterlisted.com/guides/remove-sulfur-smell-well-water/)
- [Septic dry well: what it is, how far it must be from your well, and what to test](https://waterlisted.com/guides/septic-dry-well/)
- [Septic system and well water: how contamination happens, which tests show it, and when to retest](https://waterlisted.com/guides/septic-system-and-well-water/)
- [Septic system maintenance for well owners: pumping, state rules, drainfield care and the yearly water test](https://waterlisted.com/guides/septic-system-maintenance/)
- [How to shock chlorinate a well: bleach amounts, steps and safety from state and federal procedures](https://waterlisted.com/guides/shock-chlorinate-well/)
- [UV light for well water: when your bacteria results call for it](https://waterlisted.com/guides/uv-light-well-water/)
- [Your Water Quality Report (CCR): How to Find It, Read It, and What It Leaves Out](https://waterlisted.com/guides/water-quality-report/)
- [Water softener vs water filter: which one your well test calls for](https://waterlisted.com/guides/water-softener-vs-filter/)
- [Septic system cost: installation, replacement and a well-and-septic budget, from public figures only](https://waterlisted.com/guides/well-and-septic-cost/)
- [Well flow test (yield test): how it's done and what passes](https://waterlisted.com/guides/well-flow-test/)
- [Well and septic inspection: what each one checks, who may do it, what it costs and what home sales require](https://waterlisted.com/guides/well-inspection/)
- [USDA well grants and state programs that help pay for well repairs and treatment](https://waterlisted.com/guides/well-repair-grants/)
- [How far should a well be from a septic tank? Minimums from 36 state rules](https://waterlisted.com/guides/well-septic-setback-distances/)
- [Well water maintenance: a yearly and seasonal checklist, and where official schedules disagree](https://waterlisted.com/guides/well-water-maintenance/)
- [Well water smells, tastes or stains: what it means, which test to order, what fixes it](https://waterlisted.com/guides/well-water-smell-taste-stains/)
- [VA, FHA and USDA well water test requirements, quoted from the current handbooks](https://waterlisted.com/guides/well-water-test-fha-va-usda/)
- [Well water test kits vs. a certified lab: what home kits can and can't tell you](https://waterlisted.com/guides/well-water-test-kits-vs-lab/)
- [How much does well water testing cost? Official prices, test by test](https://waterlisted.com/guides/well-water-testing-cost/)
- [Well water treatment by test result: which technology fixes what, and what doesn't](https://waterlisted.com/guides/well-water-treatment-by-test-result/)
- [Well water vs. city water: who tests it, what it costs, which is safer](https://waterlisted.com/guides/well-water-vs-city-water/)

## Tools
- [Check my ZIP](https://waterlisted.com/check/): county private-well data (USGS), EPA radon zone, state testing advice and the nearest certified labs by straight-line distance
- [Which tests do I need?](https://waterlisted.com/which-tests/)
- [What do my results mean?](https://waterlisted.com/results/)
- [Well volume and bleach calculator](https://waterlisted.com/well-volume-calculator/): gallons of standing water by casing diameter, then the bleach amount by the MDH, CDC, Pennsylvania DEP, Vermont and Wisconsin DNR methods, contact time and coliform retest timing

## Method
- [Sources and method](https://waterlisted.com/sources/)
- [Terms of use](https://waterlisted.com/terms/)

## Backflow testers

Companies on U.S. water utilities' own backflow tester lists (33 utilities, compiled 2026-11-15). Company-level details only (no individual testers); sorted A to Z; not an endorsement. Confirm with your utility before booking.

- [Backflow testing near me](https://waterlisted.com/backflow/): hub, utilities by state
- [How much does a backflow test cost? Tester prices, plus what your utility adds](https://waterlisted.com/backflow/backflow-testing-cost/): A backflow test is two bills: the tester's price and your water utility's fees. Here are testers' published prices, each utility's own filing, program and penalty fees, and what a failed test or a missed deadline adds.
- [Failed backflow test: what failed, your repair deadline, and when to replace the device](https://waterlisted.com/backflow/failed-backflow-test/): A failed test means one valve missed its pass line, not that backflow happened, but it starts a deadline for repair, retest and a report to your utility. Here is what failed, how long each state and utility gives you, when a repair is enough and when the rules force a replacement, who may do the work, and what happens if the date passes.
- [What is a backflow test? What the tester measures, what passes, and what you have to do](https://waterlisted.com/backflow/how-backflow-testing-works/): A certified tester puts a differential pressure gauge on your backflow assembly and checks that each valve holds or opens at a published minimum. Here is what each reading means, how often your utility can require it, and what you have to do after a notice.
- [Irrigation backflow testing: which device your sprinkler system needs, when it is tested, and how to winterize it](https://waterlisted.com/backflow/irrigation-backflow-testing/): A lawn sprinkler system on city water needs a backflow device, and the rules for it follow the irrigation calendar. Here is which device each state's rules call for, how often it is tested, how spring start-up and winter draining affect the test, and what changes when you replace or move it.
- [Beaumont, CA: Beaumont-Cherry Valley Water District](https://waterlisted.com/backflow/ca/bcvwd/): 66 companies, 80 testers; source: https://bcvwd.gov/wp-content/uploads/2026/08/Tester-List-08-04-2026.pdf (Revised 2026-08-04)
- [Corte Madera, CA: Marin Water](https://waterlisted.com/backflow/ca/marin-water/): 32 companies, 65 testers; source: https://marinwater.org/list-of-certified-backflow-testers/ (Revised Oct. 23, 2026)
- [Escondido, CA: City of Escondido Utilities, Water Division](https://waterlisted.com/backflow/ca/escondido/): 92 companies, company-level list (no tester count); source: https://www.escondido.gov/BusinessDirectoryii.aspx?ysnShowAll=1&lngNewPage=0&lngBusinessCategoryID=31 (directory as fetched (97 listings))
- [Irvine, CA: Irvine Ranch Water District](https://waterlisted.com/backflow/ca/irwd/): 82 companies, 114 testers; source: https://www.irwd.com/wp-content/uploads/2026/07/IRWD-BACKFLOW-TESTER-LIST-5_18_26.pdf (5_18_26)
- [Modesto, CA: City of Modesto Water Division](https://waterlisted.com/backflow/ca/modesto/): 57 companies, 57 testers; source: https://www.modestogov.com/BusinessDirectoryii.aspx?ysnShowAll=1&lngNewPage=0&lngBusinessCategoryID=0 (directory as fetched (57 listings))
- [Oakland, CA: East Bay Municipal Utility District](https://waterlisted.com/backflow/ca/ebmud/): 82 companies, 89 testers; source: https://www.ebmud.com/download_file/force/59172/750?Approved_Backflow_Testers_10.2026.pdf (Printed 2026-10-05)
- [Oakley, CA: Diablo Water District](https://waterlisted.com/backflow/ca/diablo-water/): 6 companies, company-level list (no tester count); source: https://www.diablowater.gov/certified-backflow-tester-list (Effective September 21, 2026)
- [Riverside, CA: Riverside Public Utilities](https://waterlisted.com/backflow/ca/riverside/): 89 companies, company-level list (no tester count); source: https://riversideca.gov/utilities/sites/riversideca.gov.utilities/files/pdf/2026/Backflow-Tester-List-6.1.26.pdf (6.1.26)
- [Sacramento, CA: City of Sacramento Dept of Utilities](https://waterlisted.com/backflow/ca/sacramento/): 64 companies, 101 testers; source: https://www.cityofsacramento.gov/content/dam/portal/dou/utilities/water/documents/Backflow%20Tester%20List%207.2026.pdf (7.2026)
- [Eagle, CO: Town of Eagle](https://waterlisted.com/backflow/co/eagle/): 46 companies, 92 testers; source: https://www.townofeagle.org/DocumentCenter/View/19433 (undated (PDF modified 13 Feb 2024))
- [City of Tampa Water Department, FL: City of Tampa Water Department](https://waterlisted.com/backflow/fl/tampa/): 114 companies, company-level list (no tester count); source: https://www.tampa.gov/sites/default/files/document/2026/certified-swiftcomply-backflow-testers-9.14.26-revised.pdf (9.14.26-revised)
- [Hillsborough County Water Resources, FL: Hillsborough County Water Resources](https://waterlisted.com/backflow/fl/hillsborough-county/): 251 companies, company-level list (no tester count); source: https://hcfl.gov/residents/property-owners-and-renters/water-and-sewer/certified-backflow-testers (JSON feed, newest record modified 2025-04-02)
- [Tallahassee, FL: City of Tallahassee Underground Utilities, Cross Connection Control](https://waterlisted.com/backflow/fl/tallahassee/): 45 companies, company-level list (no tester count); source: https://www.talgov.com/Uploads/Public/Documents/you/testers.pdf (Revised January 2025)
- [Athens, GA: Athens-Clarke County Public Utilities](https://waterlisted.com/backflow/ga/athens-clarke/): 51 companies, company-level list (no tester count); source: https://accgov.com/DocumentCenter/View/67445/Certified-Backflow-Tester-List-3-31-20 (Updated 2026-02-04)
- [Hilo, HI: Hawaii County Department of Water Supply](https://waterlisted.com/backflow/hi/hawaii-dws/): 11 companies, 16 testers; source: https://www.hawaiidws.org/wp-content/uploads/2026/04/CertTesterList2026-1.pdf (April 24, 2026)
- [Holland, MI: Holland Board of Public Works](https://waterlisted.com/backflow/mi/holland-bpw/): 29 companies, company-level list (no tester count); source: https://hollandbpw.com/en/customer-service/rebates/water/140-certified-backflow-device-testers-1/file (undated (PDF created 18 Feb 2026))
- [Boone, NC: Town of Boone Public Utilities and Engineering](https://waterlisted.com/backflow/nc/boone/): 21 companies, company-level list (no tester count); source: https://boonenc.gov/DocumentCenter/View/4200/Certified-Backflow-Tester-List--Updated-07142025-PDF (JULY 14TH, 2025)
- [Gastonia, NC: Two Rivers Utilities (City of Gastonia / Gaston County)](https://waterlisted.com/backflow/nc/gastonia-tru/): 41 companies, 58 testers; source: https://gastonianc.gov/images/Kristina/TRU_Approved_List_of_Backflow_Testers_2025_Accessible.pdf (2025)
- [Greenville, NC: Greenville Utilities Commission (GUC)](https://waterlisted.com/backflow/nc/guc/): 34 companies, 43 testers; source: https://www.guc.com/sites/default/files/uploads/approved-bf-tester-list-2026.pdf (Effective 03/31/2026)
- [Wilmington, NC: Cape Fear Public Utility Authority](https://waterlisted.com/backflow/nc/cfpua/): 81 companies, company-level list (no tester count); source: https://www.cfpua.org/727/Certified-Backflow-Testers-PDF (Revision 66 (8/13/26))
- [Columbus, OH: City of Columbus Dept. of Public Utilities, Backflow Compliance Office](https://waterlisted.com/backflow/oh/columbus/): 144 companies, 349 testers; source: https://www.columbus.gov/files/sharedassets/city/v/27/utilities/documents/water-forms/approvedtestersalldevices.pdf (Created 2026-10-30; valid through 2026-11-14)
- [Clackamas, OR: Clackamas River Water](https://waterlisted.com/backflow/or/clackamas-river-water/): 30 companies, company-level list (no tester count); source: https://www.clackamasriverwater.gov/files/52e9aaea7/Public+List+Of+Backflow+Testing+Companies.pdf (undated (PDF created 28 Jul 2026))
- [Cornelius, OR: City of Cornelius](https://waterlisted.com/backflow/or/cornelius/): 15 companies, company-level list (no tester count); source: https://www.corneliusor.gov/DocumentCenter/View/1969/Certified-Backflow-Device-Testers---2026-PDF (2026 (PDF created 24 Sep 2026))
- [Memphis, TN: Memphis Light, Gas and Water, Cross Connection Program](https://waterlisted.com/backflow/tn/mlgw/): 173 companies, company-level list (no tester count); source: https://www.mlgw.com/images/content/files/pdf/Companies_for_website_testingcompanies.pdf (undated (PDF created 13 Mar 2026))
- [Burleson, TX: City of Burleson Public Works](https://waterlisted.com/backflow/tx/burleson/): 34 companies, 54 testers; source: https://www.burlesontx.com/DocumentCenter/View/31383 (last modified May 29, 2024)
- [College Station, TX: City of College Station Backflow Prevention and Cross-Connection Control](https://waterlisted.com/backflow/tx/college-station/): 51 companies, company-level list (no tester count); source: https://www.cstx.gov/media/1hzno1mm/backflowpreventionassemblytesterlist.pdf (registered as of 4/25/23)
- [Corpus Christi, TX: City of Corpus Christi Water, Backflow Prevention Program](https://waterlisted.com/backflow/tx/corpus-christi/): 273 companies, 296 testers; source: https://www.envirotrax.com/registrations.aspx?at=1&wid=1246 (live registry as fetched (297 registered testers))
- [Galveston, TX: City of Galveston Development Services, Building Division](https://waterlisted.com/backflow/tx/galveston/): 103 companies, company-level list (no tester count); source: https://www.galvestontx.gov/DocumentCenter/View/5895/Backflow-Tester-List-as-of (Registered Backflow Technician list (undated))
- [Houston, TX: City of Houston Public Works, Cross Connection Control Program](https://waterlisted.com/backflow/tx/houston/): 326 companies, company-level list (no tester count); source: https://www.houstonpublicworks.org/sites/g/files/nwywnm456/files/005_cccp_backflow_tester_list_10.01.2026.pdf (October 2026 (generated 2026-10-01))
- [Round Rock, TX: City of Round Rock Utilities and Environmental Services](https://waterlisted.com/backflow/tx/round-rock/): 98 companies, company-level list (no tester count); source: https://www.roundrocktexas.gov/wp-content/uploads/2026/06/List-of-Registered-Testers-6.29.26.pdf (Revised 2026-06-29)
- [Salt Lake City, UT: Salt Lake City Public Utilities](https://waterlisted.com/backflow/ut/slc/): 35 companies, company-level list (no tester count); source: https://www.slcdocs.com/utilities/PDF%20Files/CrossConnections/BackflowLocalTesters.pdf (undated (PDF created 1 Aug 2024))
- [Appomattox, VA: Town of Appomattox](https://waterlisted.com/backflow/va/appomattox/): 13 companies, company-level list (no tester count); source: https://www.townofappomattox.com/media/896 (Updated October 2024)
- [Norfolk, VA: City of Norfolk Department of Utilities, Office of Cross Connections](https://waterlisted.com/backflow/va/norfolk/): 104 companies, company-level list (no tester count); source: https://norfolk.gov/DocumentCenter/View/2699/BACKFLOW-DEVICE--TESTERS--LIST_-2026 (2026 (PDF modified 5 Feb 2026))

## Home hazard testing labs

Labs accredited for asbestos (NIST NVLAP, as listed 2026-11-07) and lead (EPA NLLAP, October, 2026 Round 132, Month 3 of 3). Business details only; not an endorsement; confirm the test with the lab. Mold: link to AIHA LAP's own directory.

- [Asbestos testing labs](https://waterlisted.com/asbestos-testing/): 213 NVLAP-accredited U.S. lab sites by state, with bulk (PLM) / airborne (TEM) scope
- [Lead paint testing labs](https://waterlisted.com/lead-paint-testing/): 80 commercially available EPA NLLAP labs by state
- [Asbestos testing lab prices](https://waterlisted.com/asbestos-testing/lab-prices/): published homeowner prices of 17 NIST NVLAP-listed lab firms, as printed on their own sites (read 2026-11-13)
- [Mold testing](https://waterlisted.com/mold-testing/): where to find an AIHA LAP (EMLAP) accredited lab
- [Asbestos testing labs in Arizona](https://waterlisted.com/asbestos-testing/az/): 6 NVLAP sites
- [Asbestos testing labs in California](https://waterlisted.com/asbestos-testing/ca/): 47 NVLAP sites
- [Asbestos testing labs in Colorado](https://waterlisted.com/asbestos-testing/co/): 6 NVLAP sites
- [Asbestos testing labs in Connecticut](https://waterlisted.com/asbestos-testing/ct/): 3 NVLAP sites
- [Asbestos testing labs in Florida](https://waterlisted.com/asbestos-testing/fl/): 12 NVLAP sites
- [Asbestos testing labs in Georgia](https://waterlisted.com/asbestos-testing/ga/): 3 NVLAP sites
- [Asbestos testing labs in Illinois](https://waterlisted.com/asbestos-testing/il/): 6 NVLAP sites
- [Asbestos testing labs in Indiana](https://waterlisted.com/asbestos-testing/in/): 3 NVLAP sites
- [Asbestos testing labs in Maryland](https://waterlisted.com/asbestos-testing/md/): 4 NVLAP sites
- [Asbestos testing labs in Massachusetts](https://waterlisted.com/asbestos-testing/ma/): 5 NVLAP sites
- [Asbestos testing labs in Michigan](https://waterlisted.com/asbestos-testing/mi/): 6 NVLAP sites
- [Asbestos testing labs in New Jersey](https://waterlisted.com/asbestos-testing/nj/): 6 NVLAP sites
- [Asbestos testing labs in New York](https://waterlisted.com/asbestos-testing/ny/): 20 NVLAP sites
- [Asbestos testing labs in North Carolina](https://waterlisted.com/asbestos-testing/nc/): 6 NVLAP sites
- [Asbestos testing labs in Ohio](https://waterlisted.com/asbestos-testing/oh/): 3 NVLAP sites
- [Asbestos testing labs in Pennsylvania](https://waterlisted.com/asbestos-testing/pa/): 6 NVLAP sites
- [Asbestos testing labs in South Carolina](https://waterlisted.com/asbestos-testing/sc/): 3 NVLAP sites
- [Asbestos testing labs in Texas](https://waterlisted.com/asbestos-testing/tx/): 20 NVLAP sites
- [Asbestos testing labs in Virginia](https://waterlisted.com/asbestos-testing/va/): 10 NVLAP sites
- [Asbestos testing labs in Washington](https://waterlisted.com/asbestos-testing/wa/): 10 NVLAP sites
- [Lead paint testing labs in California](https://waterlisted.com/lead-paint-testing/ca/): 11 NLLAP labs
- [Lead paint testing labs in Indiana](https://waterlisted.com/lead-paint-testing/in/): 3 NLLAP labs
- [Lead paint testing labs in Maryland](https://waterlisted.com/lead-paint-testing/md/): 4 NLLAP labs
- [Lead paint testing labs in Michigan](https://waterlisted.com/lead-paint-testing/mi/): 3 NLLAP labs
- [Lead paint testing labs in New Jersey](https://waterlisted.com/lead-paint-testing/nj/): 5 NLLAP labs
- [Lead paint testing labs in New York](https://waterlisted.com/lead-paint-testing/ny/): 9 NLLAP labs
- [Lead paint testing labs in North Carolina](https://waterlisted.com/lead-paint-testing/nc/): 4 NLLAP labs
- [Lead paint testing labs in Ohio](https://waterlisted.com/lead-paint-testing/oh/): 4 NLLAP labs
- [Lead paint testing labs in Pennsylvania](https://waterlisted.com/lead-paint-testing/pa/): 4 NLLAP labs
- [Lead paint testing labs in Texas](https://waterlisted.com/lead-paint-testing/tx/): 5 NLLAP labs
- [Lead paint testing labs in Virginia](https://waterlisted.com/lead-paint-testing/va/): 4 NLLAP labs
- [Asbestos test kit vs lab: what a home kit really is and when to use an accredited lab](https://waterlisted.com/asbestos-testing/test-kit-vs-lab/): The asbestos test kits we read are a bag, gloves and a mailer; the test happens in a lab. Here is what kit sellers publish about lab fees and labs, how to check a kit's lab in the NIST directory, what one sample can and cannot show, and when a state or OSHA rule makes a kit result not enough.
- [How to test a popcorn ceiling for asbestos: what the ban dates mean, how many samples, and what to do with the result](https://waterlisted.com/asbestos-testing/popcorn-ceiling/): Only a lab can tell you whether a popcorn ceiling contains asbestos. Here is what the federal bans actually covered and when, how many samples a ceiling needs under the federal sampling standard, why paint and drywall layers are reported separately, what several states say about who may sample, one lab's published prices, and what the agencies say to do with each result.

## Septic and well inspection at house sale

Official state, county and township rules that require a septic (or well) inspection or test when a house is sold, checked 2026-11-09. Each page links the official rule; summaries are not legal advice.

- [Septic inspection when selling a house: rules by state](https://waterlisted.com/septic-inspection/): 13 statewide and 103 local rules
- [Septic inspection at sale in Arizona](https://waterlisted.com/septic-inspection/az/)
- [Septic inspection at sale in California](https://waterlisted.com/septic-inspection/ca/)
- [Septic inspection at sale in Colorado](https://waterlisted.com/septic-inspection/co/)
- [Septic inspection at sale in Delaware](https://waterlisted.com/septic-inspection/de/)
- [Septic inspection at sale in Florida](https://waterlisted.com/septic-inspection/fl/)
- [Septic inspection at sale in Iowa](https://waterlisted.com/septic-inspection/ia/)
- [Septic inspection at sale in Indiana](https://waterlisted.com/septic-inspection/in/)
- [Septic inspection at sale in Kansas](https://waterlisted.com/septic-inspection/ks/)
- [Septic inspection at sale in Massachusetts](https://waterlisted.com/septic-inspection/ma/)
- [Septic inspection at sale in Maryland](https://waterlisted.com/septic-inspection/md/)
- [Septic inspection at sale in Maine](https://waterlisted.com/septic-inspection/me/)
- [Septic inspection at sale in Michigan](https://waterlisted.com/septic-inspection/mi/)
- [Septic inspection at sale in Minnesota](https://waterlisted.com/septic-inspection/mn/)
- [Septic inspection at sale in New Hampshire](https://waterlisted.com/septic-inspection/nh/)
- [Septic inspection at sale in New Jersey](https://waterlisted.com/septic-inspection/nj/)
- [Septic inspection at sale in New Mexico](https://waterlisted.com/septic-inspection/nm/)
- [Septic inspection at sale in New York](https://waterlisted.com/septic-inspection/ny/)
- [Septic inspection at sale in Ohio](https://waterlisted.com/septic-inspection/oh/)
- [Septic inspection at sale in Oregon](https://waterlisted.com/septic-inspection/or/)
- [Septic inspection at sale in Rhode Island](https://waterlisted.com/septic-inspection/ri/)
- [Septic inspection at sale in South Dakota](https://waterlisted.com/septic-inspection/sd/)
- [Septic inspection at sale in Washington](https://waterlisted.com/septic-inspection/wa/)
- [Septic inspection at sale in Wisconsin](https://waterlisted.com/septic-inspection/wi/)
- [Septic inspection cost: what counties actually charge, and what drives a private inspector's price](https://waterlisted.com/septic-inspection/cost/): There is no official national price for a septic inspection, but counties publish what they charge. Here are the dated fees from county schedules in Colorado, Michigan, New York, Ohio and Washington, the few official statements of private prices, and what pushes a quote up.