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Updated: Jun 15, 2026
12:44
Watershed Planning within a Quantitative Scenario Analysis Framework
Published on: July 24, 2016
A water quality model for regional stream assessment and conservation strategy development
Marcia S Meixler1, Mark B Bain
1Department of Natural Resources, Cornell University, Ithaca, NY 14853, USA. MSM10@cornell.edu
Environmental Management
|March 3, 2010
Summary
Non-point-source (NPS) pollution impairs US streams. A new GIS model rapidly assesses NPS pollution (total phosphorus, total nitrogen, suspended solids) at the reach scale, aiding watershed planning where data is scarce.
Area of Science:
- Environmental Science
- Hydrology
- Geographic Information Systems (GIS)
Background:
- Non-point-source (NPS) pollution is the leading cause of stream impairment in the U.S.
- NPS pollution contributes to eutrophication, sedimentation, and hypoxia, degrading water quality.
- Accurate NPS pollution assessment is crucial for effective conservation strategies.
Purpose of the Study:
- To develop a rapid, landscape-scale GIS model for NPS pollution assessment.
- To evaluate total phosphorus (TP), total nitrogen (TN), and suspended solids (SS) at the reach scale.
- To provide a tool for watershed planning with minimal data requirements.
Main Methods:
- Utilized a GIS-based modeling approach.
- Incorporated curve numbers, literature-derived pollution concentrations, and land status data.
- Tested the model in the Chesapeake Bay and Lake Ontario watersheds.
Main Results:
- The model provided realistic water quality class distributions at the reach scale.
- Model application in Lake Ontario tributaries proved useful for watershed managers.
- Identified the model's utility in data-scarce regions and for comparative assessments.
Conclusions:
- The developed GIS model offers a practical solution for landscape-scale NPS pollution assessment.
- It aids managers in identifying pollution hotspots and prioritizing conservation efforts.
- The model is valuable for regional assessments and in areas with limited existing data.
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