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Infiltration of stormwater is prohibited in areas within DWSMAs having high or very high vulnerability or areas within Emergency Response Areas. The following steps describe how to identify these features.
 
Infiltration of stormwater is prohibited in areas within DWSMAs having high or very high vulnerability or areas within Emergency Response Areas. The following steps describe how to identify these features.
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The images on the left and right are used to illustrate these steps. '''Click on any image to enlarge it.'''
  
 
1. Go to the Special and impaired waters search tool - [https://www.pca.state.mn.us/water/stormwater-special-and-impaired-waters-search click here].
 
1. Go to the Special and impaired waters search tool - [https://www.pca.state.mn.us/water/stormwater-special-and-impaired-waters-search click here].

Revision as of 21:41, 20 December 2017

The Special and impaired waters search tool is used to find special or impaired waters near stormwater sites that require an NPDES stormwater permit. This page provides guidance for using the search tool to find specific conditions applicable to the permitted site.

To link to the Special and impaired waters search tool, click here.

Finding Drinking Water Source Management Areas (DWSMAs) and Emergency Response Areas (ERAs)

DWSMA image
To display the layers of interest, expand the layer list.
DWSMA image
Scroll up and down the list and check the desired boxes and uncheck boxes you do not want displayed.
DWSMA image
With only the Emergency Response Area and Drinking Water Supply boxes checked (all others unchecked), the map will look like this.
DWSMA image
Go to the site of interest by magnifying the image or entering an address. In this example, four sites are shown. Make sure the Legend (lower left) displays the proper legend. Infiltration is prohibited at site 1 because it is in an Emergency response Area. Infiltration is prohibited at site 2 because it is a DWSMA with high vulnerability. Infiltration is acceptable at site 3 because it is not in an ERA and is in a low vulnerability DWSMA. Infiltration is acceptable at site 4 because it is outside an ERA and DWSMA.

Infiltration of stormwater is prohibited in areas within DWSMAs having high or very high vulnerability or areas within Emergency Response Areas. The following steps describe how to identify these features.

The images on the left and right are used to illustrate these steps. Click on any image to enlarge it.

1. Go to the Special and impaired waters search tool - click here.

2. Click on the Special and impaired waters search link (or the map).

3. If applicable, click OK to the prompt on the screen.

4. In the upper right portion of the screen look for Map Layers. Click on the arrow next to Special Waters to expand the list of layers.

5. Scroll up or down the list of layers. Check the boxes labeled Emergency Response Area and Drinking Water Supply. These are the layers of interest. Uncheck all boxes that you do not want to display. Since we are interested in ERAs and DWSMAs, you'll probably want all other boxes unchecked.

6. At this point you should have a state map with only letters from the DWSMA layer displayed. The ERA and DWSMA polygons will display once you've zoomed in to your site.

7. Zoom in to your site or use the address box to zoom in to your site. At this point you can size the map as desired to make your determination. Infiltration of stormwater is prohibited in areas within DWSMAs having high or very high vulnerability or areas within Emergency Response Areas.

The image to the right illustrates four example sites.

  • Infiltration is prohibited at site 1 because it is in an Emergency Response Area.
  • Infiltration is prohibited at site 2 because it is a DWSMA with high vulnerability.
  • Infiltration is acceptable at site 3 because it is not in an ERA and is in a low vulnerability DWSMA.
  • Infiltration is acceptable at site 4 because it is outside an ERA and DWSMA.