City of Round Rock Environmental Sciences Laboratory
Water testing lab in Round Rock, Williamson County, Texas.
Independent directory. Listings come from the TCEQ Public Water System Lab Map Table (updated 03/26/2026). These labs are accredited for public drinking-water samples; call first to confirm they accept private-well samples, which tests they run, sample bottles, drop-off hours and price.
City of Round Rock Environmental Sciences Laboratory
5200 North IH 35, Round Rock, TX 78681 · map (OpenStreetMap)
Phone: (512) 218-5559
Bacteria (total coliform / E. coli)