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Effluent Guidelines

National Study of Nutrient Removal and Secondary Technologies

""Back River Wastewater Treatment Plant, Baltimore.


""Nutrient pollution is one of America’s most widespread, costly and challenging environmental problems impacting water quality. Excessive nitrogen and phosphorus in our waters can lead to a variety of problems including eutrophication and harmful algal blooms, with impacts on drinking water, recreation and aquatic life. A wide range of human activities can contribute to nutrient pollution including stormwater runoff, agriculture, and wastewater discharges.

""Many POTWs have added treatment processes for extensive nutrient removal, but these upgrades are not affordable or necessary for all facilities. Some POTWs have reduced their nutrient discharges by optimizing operation and maintenance practices without incurring large capital expenses.

Improving Nutrient Removal at POTWs

Currently, there are no comprehensive nationwide data on nutrient discharges and removal at POTWs. EPA and POTWs can use the information gathered from this study to learn about low-cost, effective solutions for reducing nutrient discharges.

Study Goals

  1. Obtain nationwide data on nutrient removal to help set more realistic and achievable nutrient reduction targets.
  2. Encourage improved POTW performance with less expense.
  3. Provide a forum for stakeholders to share best practices.

Study Design

""EPA plans to collect basic information from all facilities nationwide using an interactive, online screening questionnaire. The screener will collect data on technology in place and typical operations challenges. The questionnaire is tailored to minimize the number of questions, and reduce burdens on facilities that have limited staff available.

Following the screening questionnaire, EPA plans to select a sample of facilties for further study, through a detailed questionnaire, or influent/effluent sampling.

Many people reviewed the September 2016 draft questionnaire and provided EPA with useful comments. The comments have been addressed and the revised questionnaire has been converted into an on-line electronic format. EPA expects to distribute the questionnaire in early 2018.

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Benefits to POTWs

""The multi-phase study will:
  • Help POTWs optimize nutrient removal by providing operation and performance information from similar types of POTWs that have already achieved cost-effective approaches to nutrient removal.
  • Serve as a major new nationwide data resource on nutrient removal to help stakeholders evaluate and develop achievable nutrient reduction values.
  • Provide a rich database of nutrient removal performance for POTWs, states, academic researchers, and other interested parties.

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EPA plans to publish a revised draft questionnaire in the Federal Register in fall 2017.

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Additional Resources

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Additional Information

For more information on the study, please send inquiries to nutrient-removal-study@epa.gov.

Photo credits:
Jane Thomas, Integration and Application Network, University of Maryland Center for Environmental Science.Exit

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