Maximizing the 2016 construction year, VLAWMO was able to complete about 85% of a streambank restoration just before the ground froze last Fall. The restoration is a portion of Lambert Creek, as it crosses Kohler Road. Initially, the project may look like the brush was simply cleared. Looking closer however, we can see a number of strategies at work to improve the creek’s function and water quality. 

 While clearing vegetation and creating open space may seem counter-intuitive to a stream restoration, this first step is really an adjustment for a healthier suburban waterway. Pictured right is the creek before the restoration - erosion can be seen on the banks despite the tree cover. One of the reasons for this is that a suburban creek such as this receives large amounts of runoff from the surrounding area (roads, rooftops, etc.), unlike a forest creek that’s surrounded by thick vegetation and uses the forest floor to move the water slowly. With high flows coming in from rain events, a suburban creek functions closer to a prairie or savannah stream. Here, the creek acts as a break in the tree canopy, allowing light to reach the banks. Instead of woody vegetation, native grasses and thick shrubs fill the space both providing density and sunlight as well as protecting the soil. While woody vegetation grows upward, grasses provide a dense cover and a deep root mass that slows water at the surface and holds it like a sponge as the creek’s shallow groundwater ebbs and flows with the seasons.

What’s been done on the project so far?

• Tree removal for 125 feet of streambank. Select mature, native trees are kept intact to maintain habitat use and preserve neighborhood foliage. Most vegetation removed is invasive buckthorn – the contractor will be working with the City of Vadnais Heights to do additional clearing this spring.
• Drop structure. To catch high-velocity runoff coming from Kohler road, a drop structure is like a hidden waterfall to absorb the velocity. As water rushes from the street, it falls into an enclosed hole that absorbs the impact. Water leaving the drop structure exits from the ground at the water level, rather than from above at the bank surface. This greatly reduces erosion of the bank.
• Soil lifts. Creating a “step” structure in the stream bank is supported by bringing in soil lifts, which are like flexible logs filled with natural material. Laid along the stream, they’ll be encompassed into the soil when the new plants grow.
• Erosion blankets. This blanket serves to hold soil in place in the transition, and support new plant growth by protecting and structuring
• Spring, 2017 completion:
• Planting: New plants will consist of willow and dogwood stakes, seed, and plugs.
• Finalizing grading and erosion repair.

The Ramsey Conservation District (RCD) assisted with project design and contributed Clean Water Funds.

Stay tuned to the VLAWMO news and blog pages for more photos and updates as the project continues this Spring!