CITY OF SAN MARCOS
TX · PWS ID TX1050001 · Community water system
110
contaminants tested
31
detected
72,970
people served
PFAS detected
“Forever chemicals” from UCMR-5 — the only fresh nationwide measurements (2023–2025).
| Contaminant | Max | Detection rate | Period |
|---|---|---|---|
| PFPeA | 0.0042 ug/L | 6/26 | 2024 |
| PFHxS | 0.0034 ug/L | 3/26 | 2024 |
| PFBA | 0.0114 ug/L | 2/26 | 2024 |
Other contaminants detected
| Contaminant | Max | Detection rate | Source | Period |
|---|---|---|---|---|
| Dibromochloromethane | 33.7 UG/L | 282/288 | SYR4 | 2012–2019 |
| Bromoform | 10.3 UG/L | 274/288 | SYR4 | 2012–2019 |
| Bromodichloromethane | 33.9 UG/L | 272/288 | SYR4 | 2012–2019 |
| Chloroform | 124 UG/L | 248/288 | SYR4 | 2012–2019 |
| TTHM | 158 UG/L | 246/251 | SYR4 | 2012–2019 |
| Total Haloacetic Acids (HAA5) | 142 UG/L | 236/247 | SYR4 | 2012–2019 |
| Dibromoacetic acid | 8.9 UG/L | 234/247 | SYR4 | 2012–2019 |
| Dichloroacetic Acid | 50.2 UG/L | 223/247 | SYR4 | 2012–2019 |
| Trichloroacetic Acid | 86.5 UG/L | 206/247 | SYR4 | 2012–2019 |
| COPPER, FREE | 740 UG/L | 200/210 | SYR4 | 2012–2018 |
| Nitrate | 2580 UG/L | 114/114 | SYR4 | 2012–2019 |
| Lead | 24 UG/L | 101/210 | SYR4 | 2012–2018 |
| Monobromoacetic acid | 4.1 UG/L | 50/247 | SYR4 | 2012–2019 |
| Monochloroacetic acid | 16.3 UG/L | 40/247 | SYR4 | 2012–2019 |
| Chlorite | 692 UG/L | 35/48 | SYR4 | 2017–2019 |
| Barium | 48.9 UG/L | 33/33 | SYR4 | 2013–2019 |
| Fluoride | 840 UG/L | 31/31 | SYR4 | 2012–2019 |
| LEAD SUMMARY | 0.0067 mg/L | 14/14 | LCR | 2024 |
| Nitrate-Nitrite | 2300 UG/L | 9/9 | SYR4 | 2012–2015 |
| lithium | 11.3 ug/L | 5/26 | UCMR-5 | 2024 |
| Combined Radium (-226 and -228) | 1.5 PCI/L | 4/4 | SYR4 | 2017 |
| Selenium | 4.1 UG/L | 4/33 | SYR4 | 2013–2019 |
| Chromium | 1.97 UG/L | 2/33 | SYR4 | 2013–2019 |
| Antimony, Total | 0.2220 UG/L | 1/33 | SYR4 | 2013–2019 |
| Arsenic | 2.2 UG/L | 1/33 | SYR4 | 2013–2019 |
| Atrazine | 0.1600 UG/L | 1/49 | SYR4 | 2012–2019 |
| CYANIDE | 10 UG/L | 1/26 | SYR4 | 2014–2019 |
| Di(2-ethylhexyl) phthalate | 0.8700 UG/L | 1/49 | SYR4 | 2012–2019 |
79 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4,5-TP2,4-D4:2 FTS6:2 FTS8:2 FTS9Cl-PF3ONSADONAAsbestosBHC-GAMMABenzeneBenzo(a)pyreneBeryllium, TotalCHLOROBENZENECadmiumCarbofuranCarbon tetrachlorideChlordaneCombined UraniumDICHLOROMETHANEDalaponDi(2-ethylhexyl) adipateDinosebETHYLENE DIBROMIDEEndrinEthylbenzeneGross Alpha, Excl. Radon and UGross Beta Particle ActivityHEXACHLOROBENZENEHFPO-DAHeptachlorHeptachlor epoxideHexachlorocyclopentadieneLASSOMercuryMethoxychlorNEtFOSAANFDHANMeFOSAANitriteOXAMYLPFBSPFDAPFDoAPFEESAPFHpAPFHpSPFHxAPFMBAPFMPAPFNAPFOAPFOSPFPeSPFTAPFTrDAPFUnAPentachlorophenolPicloramSimazineStyreneTetrachloroethyleneThallium, TotalTolueneToxapheneTrichloroethyleneVinyl chlorideXylenes, Totalcis-1,2-Dichloroethyleneo-Dichlorobenzenep-Dichlorobenzenetrans-1,2-Dichloroethylene