WaterQualityWatch -- Continuous Real-Time Water Quality of Surface Water in the United States

USGS is updating how statistical information is delivered. WaterWatch and WaterQualityWatch will be retired around February 24, 2026. Explore alternative tools and share feedback at wdfn@usgs.gov.

How are these data used?

There are many diverse applications and uses of real-time water-quality data. Real-time and continuous data may be used to:

  • improve our understanding of hydrology and water quality and can lead to more effective resource management;
  • notify regulatory agencies and the public with information for drinking water treatment and for recreation uses;
  • notify water suppliers of changes so they can more efficiently treat drinking water using stream flow data in addition to many in-stream water quality measurements like, water temperature, specific conductance, turbidity, and pH;
  • obtain current information on whether river conditions are safe and desirable for a river-rafting trip or a fishing trip (is the water warm or cold or flooding) for recreation;
  • assess sustainability of fisheries;
  • assess beach recreation quality closures;
  • evaluate water-quality standard and criteria attainment;
  • develop surrogate relations between samples and continuous turbidity measurements to estimate concentrations of indicator bacteria to assess the sanitary quality of water for recreation;
  • improve concentration and load estimates with defined uncertainty (based on 8,760 hourly values per year, for example);
  • measure seasonal, diel (daily), and event-driven fluctuations to optimize and prioritize sample collection and monitoring;
Estimated real-time fecal coliform bacteria concentration in Little Arkansas River near Sedgwick, KS Legend for graphical elements on time-series plot.

Figure showing estimates of fecal coliform bacteria and probability of exceeding water-quality criteria (http://nrtwq.usgs.gov/ks/)