U.S. Geological Survey - Environmental Health

Can There be Unintended Benefits when Wastewater Treatment Infrastructure is Upgraded?

Fathead Minnows (Pimephales Promelas) Swimming in an Expermental Aquaium

Fathead minnows (Pimephales promelas) swimming in an expermental aquaium. The aquarium is part of an experiment to assess endocrine disruption in fish. Photo Credit: Larry B. Barber, USGS.

Science from the U.S. Geological Survey (USGS) and other entities has shown that a mixture of natural and synthetic estrogens and other similar chemicals are discharged from wastewater treatment plants (WWTPs) to streams and rivers.

USGS Scientists Collecting Water-Quality Samples from Boulder Creek, Colorado

USGS scientists collecting water-quality samples for the analysis of wastewater related contaminants, Boulder Creek, Colorado. Photo Credit: Jennifer A. Beck, USGS.

USGS and University of Colorado hydrologists, chemists, geologists, and biologists studied the chemistry and biology of Boulder Creek downstream of Boulder WWTP and showed chemical and biological evidence associated with endocrine disruption in both wild and laboratory fish due to estrogen exposures.

Boulder WWTP subsequently upgraded treatment of 15 million gallons of effluent discharges per day to meet State requirements to reduce nitrates and ammonia.

An aerial photograph of the Boulder Wastewater Treatment Facility, Colorado

The Boulder Wastewater Treatment Facility, Colorado (circa 2005), before the upgrade to an activated sludge treatment process. Treated effluent from the plant is discharged to nearby Boulder Creek. In a small laboratory, seen in the lower left of the photograph, a team of scientists conducted fish exposure experiments using the treated effluent from the facility. Photo Credit: City of Boulder, Colorado.

Although the Boulder WWTP upgrade was designed for nutrient reductions it also decreased endocrine disruption in both laboratory and wild fish. This unintended benefit of a large public investment in infrastructure improvements would not have been known without the science provided by the Environmental Health Mission Area.

Stacks of experimental fish tanks in side a laboratory trailer
Fish tanks inside an onsite laboratory where fathead minnows were exposed to untreated and treated wastewater for 28 days to test for possible endocrine disruption. Photo credit: Alan Vajda, University of Colorado.

Questions We're Working On:

How do municipal wastewater treatment technologies minimize the health risk to aquatic biota exposed to novel contaminant mixtures in wastewater discharges?

How do urban stormwater management technologies minimize the health risk to aquatic biota exposed to novel contaminant mixtures?

Learn More


  Get More Environmental Health Science Stories


USGS Home Water Land Resources Science Systems Ecosystems Energy and Minerals Environmental Health Hazards

Accessibility FOIA Privacy Policies and Notices

USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
Page Content Contact Information: gs-eh_web@usgs.gov
Page URL: http://www2.usgs.gov/envirohealth/science_stories/wwtp_upgrade.html
Page Last Modified: 12-Apr-2018 @ 12:02:01 PM EDT