Douglas County Water Report

Douglas County's drinking water earned a C grade, scoring 52.5 out of 100. Over the past five years, EPA SDWIS records 53 health-based violations — a pattern that public water utilities are required to disclose and correct.

Under the Clean Water Act §303(d), EPA ATTAINS tracks whether waterways meet quality standards for drinking, recreation, and aquatic life (reporting cycle: 2022). A substantial 43.2% of assessed waterways are impaired (60 of 139 water bodies) across Douglas County's watersheds. The leading impairment causes are ph and arsenic. Impairment does not mean tap water is unsafe — it measures ambient waterway conditions upstream of treatment, not finished drinking water.

USGS NWIS gauge data (as of 2026-05-14T12:45:00.000-06:00) puts SOUTH PLATTE RIVER BLW BRUSH CRK at 184.0 cfs — running somewhat below its historical average at 86% of mean. Streamflow is a leading indicator of drought stress, sediment load, and dilution capacity: low flows concentrate pollutants and warm water temperatures, stressing aquatic life and, in surface-water-dependent systems, the source water quality for treatment plants.

EPA's Water Quality Portal (WQP) aggregates monitoring data from federal, state, and tribal agencies. Douglas County has moderate coverage with 45 active monitoring sites with 9,660 recent measurements on record. Predominant monitoring categories include nutrient and inorganics, minor, metals. More monitoring sites generally indicate greater scientific attention to local water conditions — and provide the baseline data that regulators use to set future impairment listings.