USACE Blue Marsh Lake Targeted Watershed Improvements
USACE Blue Marsh Lake Targeted Watershed Improvements
Information
Welcome to Blue Marsh Lake's Targeted Watershed Improvement Program
This site was created as a resource to help identify locations within the contributing watershed of Blue Marsh Lake for improvements. Runoff with excess nutrients entering the waterways have a negative impact on water quality and are also a factor in blue-green algae growth. Using this site we can see areas with high nutrient loading rates, highly erodible soils, exposed streams that are lacking a forested buffer, and estimated nutrient reductions via a few Best Management Practice (BMP) options. With this information you can identify locations that could benefit from BMP installation to reduce runoff from these areas.
Tools
About Blue-Green Algae
About Blue-Green Algae links to our storymap site about formation, health impacts, and other associated information on blue-green algae.
Layers
The Layers widget allows users to toggle the map layers on/off. Map layers include: NHD Streams, Exposed Streams, Contour (5' Interval), Park Boundary, Blue Marsh Lake, HUC-12 Watersheds, Soil Erodibility Factor(Kw), and Nitrogen & Phosphorus Loading. Layers that are grayed-out are not visible at that scale. Zooming in will turn on additional layers.
Basemaps
The Basemaps widget allows the user to change the basemap background between aerial, topographic, or street map variations.
Legend
The Legend widget shows users what the symbols on the map mean.
Information
Information opens this window to show additional information about this program, on the tools, data notes, and additional helpful links.
Data Notes
- Exposed Streams consist of a 100' buffer from the streams divided by drainage basins, where the landcover is either low vegetation or impervious surfaces. Landcover was calculated using Esri's High-Resolution Deep Learning model paired with 2019 NAIP Imagery. Drainage basins were delineated using the ArcGIS Hydrology toolset with 2018 PEMA Digital Elevation Models.
- Soil Erodibility Factor (Kw) represents the susceptibility of soil to erosion and the rate of runoff. Values provided are for the surface horizon of the soil.
- Nitrogen & Phosphorus loading represent the amount of nitrogen and phosphorus eroded each year per drainage basin. Data was aquired from the Model My Watershed tool from the Stroud Water Research Center's WikiWatershed initiative.
- BMP Nutrient Reduction is a layer of small drainage basins delineated from 2018 PEMA Digital Elevation Models. Some of these boundaries are not representative of reality because of the high resolution DEM coupled with limited precision of the watershed delineation tools. These boundaries were then combined with a high-resolution landcover class to calculate nitrogen and phosphorus loading rates per basin using PADEP guidance. PADEP BMP effectiveness values were used to calculate the nutrient reductions for four separate BMP types. Effectiveness of Bioretention/Raingarden and Vegetated Open Channels are dependent on soil classification and were averaged together for our purposes.