Bluff Standards Update
The Lower Minnesota River Watershed District (LMRWD) updated its Watershed Management Plan in October 2018. By State Statute, this update occurs every 10 years and local governments must comply with newly adopted standards. Among the many updates to the Plan, the District established new standards related to land-disturbing activity along the Minnesota River Bluffs and other steep slope areas within the District. To align the City and Watershed District requirements, the City updated its Bluff Protection Overlay Districts and related Code Sections through ordinances adopted on June 1, 2020.
The map above allows users to identify the extents of the city's bluff standards (green) and where there are additional standards for areas with steep slopes (red). This map can be displayed in 3D by clicking and holding the right mouse button (or using 2 fingers while navigating on a mobile device).
Areas within the Bluff Protection Overlay District are subject to the standards found in the City Code Section 21.208.02.
An outline of bluff protection standards and additional standards for areas with steep slopes is provided in the following table:
Comparison of LMRWD Steep Slope and City Bluff Standards
| Existing City BP District Standards | New LMRWD Steep Slope Standards (to be added to existing standards) |
| Where does this apply? All areas between the 722 and 800-foot elevation lines along the river valley including the Nine Mile Creek area up to 106th St. | Where does this apply? Steep Slopes of 18% or greater over 25 feet or longer |
| Regulations:
No variances are permitted, but the following exceptions to obtaining a professional’s certification are allowed:
|
Minimize stormwater runoff down the bluff
- Consider maintaining an unmowed strip of land, 10 to 20 feet, from the top of steep slopes; let deep-rooted vegetation anchor the top of the bluff slope and the bluff itself
- Minimize impervious (paved) surfaces and mowed lawn area
- Direct runoff from paved surfaces into vegetated areas
- Direct runoff away from the bluff edge to prevent soil erosion
Manage soil erosion
- Stabilize bare slopes
- Be careful when removing invasive species, which may leave soils bare and prone to erosion
- Cover bare soils with biodegradable erosion control blankets and/or logs
- Plant bare areas with seedlings or seeds of native species and mulch
Maintain a Healthy, Native Bluff Environment
- Properly dispose of yard waste, including grass clippings, leaves, twigs, and pet waste (Not over the bluff)
- Clippings may contain chemicals that wash off into the waterways
- Clippings also decompose and release nutrients, such as nitrogen, which attracts invasive species
- Piled yard waste, when left to sit, kills the underlying vegetation. This exposes those soils, and makes them more susceptible to erosion.
- Consider planting native species along a 10-20 foot buffer from the top of the slope
- Learn to identify invasive species, and consult best practices for control
The above best practices are adapted from techniques identified in the MN DNR's Conserving your blufflands booklet that was intended for property owners along the St. Croix River.
Additional information about bluff and steep slope protections are found in the MN DNR's shoreland management best practices.
Information about protecting natural resources at home and in your community are available on Hennepin County's website.
Grants are available to private property owners for small and large projects that implement some of the best practices listed above.
Hennepin County offers Natural Resource Grants for a variety of projects that preserve and restore natural areas.
The Lower Minnesota River Watershed District offers a Cost-Share Grant for properties within its district (see map above).
For properties in the Nine Mile Creek Watershed District, there is also a Cost-Share Grant available to landowners.
The Riley Purgatory Bluff Creek Watershed Districtalso offers grants to landowners within its district for small and large projects.