What's in CITY OF SAN MARCOS's water?
CITY OF SAN MARCOS had a health-based violation within the last five years. The required corrective action was reported, but it happened recently enough to matter. Population served: 72,970, over 42,746 connections.
CITY OF SAN MARCOS's record against the rest of the country
11 total violations and 7 health-based ones put CITY OF SAN MARCOS at the 78th percentile nationally for violation burden, rank 2,832 of 12,903.
How CITY OF SAN MARCOS compares within TX
CITY OF SAN MARCOS's 7 health-based violations sit above the TX average of 6.7, across 1,633 systems statewide. The filter guide explains what a violation like this actually calls for.
Most recent violation on record
The last violation EPA has on record for CITY OF SAN MARCOS is from 2025-01-10 (health-based: 2025-01-10). Last reported to EPA: 06/26/2026.
What kind of problem, specifically
CITY OF SAN MARCOS's flagged contaminants and rule violations, grouped by what they actually mean for a filter choice rather than left as EPA's raw code list:
- Microbial contamination / treatment technique - flagged from: Surface Water Treatment Rule
- Disinfection byproducts - flagged from: TTHM
The most severe category on record is microbial contamination / treatment technique, which points toward a microbial-class filter if you want to address it directly.
What this data is and is not
Everything on this page is CITY OF SAN MARCOS's own reported record under the Safe Drinking Water Act - a regulatory filing, not a sample of your tap. Water quality can still change between the meter and the faucet - household plumbing sits outside what a record of 11 logged violations can see. The guide to what this data misses covers that gap.