The following article was included in the November 2020 edition of the Minnesota Department of Natural Resources (DNR) Water Talk Newsletter. This bulletin is issued anywhere from 4 to 6 times each year.

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By Jeff Weiss, DNR, Clean Water Specialist

The Coon Creek Watershed District (CCWD) and the City of Coon Rapids have partnered with DNR Ecological and Water Resources staff to address aquatic recreation and aquatic life impairments on Sand Creek in the City of Coon Rapids.

Project goals

In 2018, a stream corridor restoration of Lower Sand Creek was implemented to reduce bank erosion and improve habitat. The partnership was awarded a second set of Clean Water Fund and US-EPA Section 319 grants for continuing stream corridor restoration in Middle Sand Creek. The project goals are to:

1. Reduce sediment and phosphorous loading from bank erosion.
2. Enhance habitat for native species.
3. Reduce the impacts of altered hydrology while accommodating floods.

Why the projects were needed

There are multiple causes for the poor condition of Sand Creek. Much of the stream channel was ditched and straightened years ago causing the channel to cut downward and lose connection to its floodplain. Urban development within Lower Sand Creek occurred before stormwater regulations were enacted. There were many direct pipes to the stream which speeds up water delivery and causes stream flows to be “flashy.”

Upper Sand Creek is in better condition than Lower Sand Creek because stormwater regulations were in place prior to development and there are wetlands and stormwater ponds that help retain water and filter pollutants.

Proposed Middle Sand Creek project

The Middle Sand Creek project area is divided into two reaches where differing techniques will be used to address problems.

• Upstream reach: Eroding banks will be stabilized using a variety of methods and instream habitat will be improved.
• Downstream reach: A newly remeandered channel and floodplain, designed by DNR Clean Water Specialist Nick Proulx and Wenck Associates, will be constructed that improve connection to the floodplain and accommodates flood flows.

The new channel will be constructed following the natural channel design principles instead of using traditional hard armoring techniques such as riprap. According to CCWD staff, there was initially public resistance due to the amount of disturbance the project would create and the number of trees that would need removal to accommodate a meandered channel. However, CCWD and DNR staff explained that the disturbance would be temporary and that tree removal was necessary to create space for the channel and the wider connected floodplain. The public has gained acceptance of the project through discussion and education.

Previous Lower Sand Creek work

Replacing invasive tree species with a variety of native vegetation in the Lower Sand Creek project area provided a glimpse of what the new project will eventually look like. Residents were also concerned about impacts to wildlife that use the stream corridor. After completion of the Lower Sand Creek project in 2019, residents believed they were seeing more wildlife use of the corridor and this helped alleviate concerns about tree removal and disturbance in the new project area.

The Lower Sand Creek project was completed in 2018-19. Half of the new channel and most of the floodplain of Middle Sand Creek were excavated in the winter of 2019-20.  Excavation work of the channel was completed “off-line” with stream flow remaining in the old channel. This re-meandered section of the stream was left dry during 2020 to allow vegetation to grow and establish root structure. During this winter, 2020-2021, the other side of the floodplain and the new channel will be constructed while the old channel will be filled, thus completing the project. 

Additional educational elements, including tours

Additional project elements to be added include interpretive signing along a popular walking path next to the stream, hosting interactive “Watershed Walks” with CCWD staff, and continued monitoring and project maintenance. The photo on the right shows Jon Janke, of Coon Creek Watershed District, giving a site tour to Anoka Ramsey Community College biology students.The Sand Creek corridor restoration will be completed soon. The partnership is now setting its sights on restoring the stream corridor of Coon Creek by applying what they have learned from the Sand Creek projects. 

For more information contact Justine Dauphinais or Jon Janke at the Coon Creek Watershed District.

Editor’s note: We have two DNR staff named Jeff Weiss. One Jeff Weiss is an engineer leading the floodplain mapping program in our St. Paul office, and the author of this article is a Clean Water Specialist in our Rochester office.

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