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

Science Center Objects

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 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.

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.

The Boulder Wastewater Treatment Facility, Colorado (circa 2005)

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.

(Public domain.)

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?