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Polluted Runoff: Nonpoint Source (NPS) Pollution

Nonpoint Source Pollution Technical Exchange Webinars

The State Nutrient Reductions Strategies Web series has merged with the Nonpoint Source (NPS) Technical Exchange forum to cover a broader variety of NPS topics.

We are currently working with our partners on new topics and new methods of engaging in discussion on current nonpoint source technical topics of interest. Stay tuned for future announcements.  In the interim, you can view PDFs of the PowerPoint presentations from some of our past webinars below.

Upcoming Webinars

No webinars are scheduled at this time.

Past Webinars

  • No materials are available yet:  Introduction to STEPL 4.4, presented by Tetra Tech Inc. on March 20, 2018.  The webcast provided an overview of  STEPL and how to use it.  STEPL is a planning-level spreadsheet model intended to facilitate the estimation of nutrient and sediment load reductions associated with Clean Water Act Section 319 projects at a HUC-12 watershed scale.  This webinar also covered some new enhancements in version 4.4. This new version:
    • incorporates new cropland and pastureland BMPs,
    • accounts for flow volume reductions from urban low impact development practices,
    • offers enhanced weather data and reporting features, and
    • includes a new manure application worksheet.
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