Shore Impact Zone Alteration Permits

The Shore Impact Zone(SIZ) is the boundary between a lake’s Ordinary High Water level (OHW) and one half of the required setback from the Ordinary High Water level set by local ordinance. The setback of the Shore Impact Zone varies based on Minnesota DNR lake classification. 

 Am I in the Shore Impact Zone (SIZ)?

Below is a list of the Shore Impact Zone setbacks for the majority of lakes within Pelican River Watershed District. Distance noted is the number of feet from the Ordinary High Water level as determined by the Minnesota DNR.


 What is an Ordinary High Water Level (OHW)?

The Ordinary High Water level (OHW) is the boundary where the highest water level between public waters/wetlands and the shore has been maintained for enough time to leave a mark on the landscape. This is commonly the point where natural vegetation changes from predominantly aquatic to predominantly terrestrial.

Below is a list of the most commonly requested Ordinary High Water levels in the District:



 Do I need a permit from PRWD?

 If you plan to undertake any land alterations within PRWD's Shore Impact Zone, your project is subject to permitting. This includes the following activities:

  • Rip-rap installation
  • Brush or tree removal
  • Ice ridge leveling or repair
  • Sand blanket installation


What does it take to get a Shore Impact Zone Alteration Permit from PRWD? 

To obtain a permit please complete and submit a signed Permit Application, Project Site Plan, and permit/inspection fees.  A District employee will then contact you to schedule a project site visit prior to permit approval.


Shore Impact Zone Alteration


Rip-rap is used a method that is used to help protect shorelines from wave action erosion and winter ice damage by the placement of rock along the shoreline.  This method works best when used in cooperation with vegetation planted within and behind the rip-rap.  Permits application are reviewed with a site visit to observe the current conditions and suitability/need for rip-rap.  While each site will differ, the guidance below will help design a plan and application which meets PRWD rules.

Rock Size and Arrangement:  Rock rip-rap consists of coarse stones, 6-30 inches in diameter, which are randomly and loosely placed.  Creating a "base row" of large rock lined up or "panning" rocks are not allowed (see photos below).  The height of the rip-rap should only extend where wave action and ice damage is an problem and the need is demonstrated.  Typically, the rip-rap height will be no higher than 3-feet above the ordinary high water (OHW) level or 1-foot above the highest known water level.  All rip-rap projects will also need to demonstrate that MN DNR guidelines are being followed.


Rock "panning" or the placement of rock which is not randomly and loosely placed is not allow.

Examples of proper and effective rip-rap are below


Good: Rocks are randomly placed and extend into the water


Better:  Plantings are installed behind rip-rap


 Best:  Planting within the rip-rap


Sand Beach Blanket

Sand Beach blankets are allowed if the shoreline topography and lake bottom is suitable to support sand without erosion.  The maximum size of the sand is 50 feet (or 1/2 the lot width, whichever is less) by 10 feet and 6 inches thick.  Sand blankets are not allowed on steep slopes or to be placed in the lake where emergent vegetation or silty lake bottom sediments are present.  All sand blanket additions will also need to follow MN DNR Guidelines.

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