gage graph for webNew measurements of water quality are now available from three river gages in the Animas River watershed. Previous real-time data at these sites included streamflow and gage height. In collaboration with the U.S. Geological Survey (USGS) and the Environmental Protection Agency, SJBH and the Colorado Department of Public Health and Environment will now be measuring pH, conductance, turbidity and temperature. These parameters do not directly measure the amount of contaminants (metals, nutrients or bacteria) present in the Animas River, but rather present a proxy for overall water quality in real time. These readings will not only be of use to frequent river recreationists, but will inform decisions such as closing agricultural diversions or city water intakes.

The USGS stations now monitoring water quality are Cement Creek at Silverton, Animas River below Silverton, and Animas River at Durango. When reading the gages:

  • Streamflow will be very low in winter and peak from May to July. Contaminant levels are generally lower during the highest flows due to dilution.
  • pH measures how acidic (values from 0 to 7) or basic (7 to 14) water is. In Cement Creek and the Upper Animas, typical values are between 3 and 7. At Durango, 7 to 9 is normal. pH outside of 6.5 to 9 is concerning for aquatic life and recreation.
  • Conductance measures how easily water transmits electrical current through dissolved ions and metals. Historic data are not available but monitoring will track large changes.
  • Turbidity measures how murky water is due to suspended solids and increases with higher streamflow as sediment is stirred up. This may not indicate health concerns.
  • Temperature in the Animas River shouldn’t exceed 20 degrees Celsius. Rapid changes in temperature can be problematic for cold-water aquatic life.

These gages are part of Colorado’s Long-Term Monitoring Plan for the Upper Animas Basin, which also includes weekly water samples for metals analysis. SJBH expects risks of spring runoff will not be different from previous years, and this monitoring plan provides data to public health and emergency managers while informing long-term watershed cleanup efforts.