Streambank erosion was identified as a concern in the 2008 Aux Sable Creek Watershed Management PlanAdvisory Committee members noted that in many reaches of the stream there is some degree of erosion. (See page 51 of the Plan). 

Streambank erosion is a natural part of a stream’s process.  However, human activities have accelerated the rate of erosion by activities that include altering a stream’s route and adding more water than naturally occurs.  Unnatural, faster rates of streambank erosion create more sediment in a stream, which results in a decline in the quality of water and habitat and often a loss of crop production area too.  Erosion issues occur in both urban and rural areas.  This section will talk about some of the common issues and suggest practices that can help to address them for both urban and rural erosion issues.


Leaving or establishing natural buffer zones along the stream are a good way to avoid erosion problems. The 2008 Aux Sable Creek Watershed Management Plan recommends a 50-100 foot riparian buffer along the edge of streams in areas being developed.  The width is dependant on the quality of the aquatic resource and regulatory requirements.  A master open space plan for the Aux Sable Creek watershed was created as a part of the 2008 Management Plan.  It identifies open space opportunities, including such buffer areas mentioned here.  If it is used as a guide, when buffer opportunities arise, then eventually we will achieve a coordinated green infrastructure (insert link to info about green infrastructure: IEPA? CW? CMAP?) implementing the watershed vision. 

The 2008 Aux Sable Creek Watershed Management Plan recommends urban stormwater Best Management Practices (BMP) to mitigate streambank erosion.  Perhaps the most effective BMP is to reduce impervious areas.  Impervious surfaces prevent water from soaking in and direct the water off the property.  It creates large amounts of water that rush into our rivers and streams.  While detention ponds mitigate this to some extent, reducing the size of our streets, sidewalks, parking lots, driveways, and roofs start at the source.  Reducing these areas reduces runoff and eliminates the forces that create erosion.  This approach is a win-win-win: 1) less cost to the developer (since they don’t have to construct large paved/roofed surfaces), 2) less cost to the community (since there is less to maintain), and 3) less water rushing into our streams when it rains.  What can be better than that?  Click here to access several fact sheets on reducing impervious surface (produced in Minnesota). Click here to link to Power Point presentation and a Resource Manual on implementing conservation design and stormwater best management practices.

Another practice that can work to reduce streambank erosion in urban areas is to design storm sewer systems that would release water at a lower rate,  so that banks are not chewed up by large flushes of water.  Additionally, these flows could be released over riparian areas (grassed strips) rather than directly to the stream.  This approach will slow down the water, infiltrate some of it and release water into the creek in a less concentrated fashion.  

Minimizing exposed soil will reduce the chances of it being washed away by rain or other traveling water.  This issue can be especially pertinent on lands that are under construction.  Most communities have regulations in place designed to minimize erosion during construction.  The 2008 Aux Sable Creek Watershed Management Plan recommends that no more than 40 acres of soil be exposed at any time during construction.  This requirement is based on other areas around the region to prevent large tracts of land with open soil which is susceptible to wind and water erosion. It is not the standard within the Aux Sable Creek Watershed at this time.  This requirement, coupled with monitoring to ensure compliance throughout the construction phase is important.  We all know things happen… so let’s plan on that and simply plan regular inspections during the construction process so that the initial effort is not wasted time or money and we maintain the quality of the Aux Sable Creek.   Click here for an example of an outreach program in Kentucky that showed the effects of exposed soil.

The point?  For the most part in urbanizing areas of the Aux Sable Creek watershed, it’s a matter of planning.  New developments can integrate approaches mentioned above and other stormwater BMPs outlined in the 2008 Aux Sable Creek Watershed Management Plan.  This does not have to cost more.  That should be the goal for both community decision makers as well as for the developer.  Redevelopment scenarios can also be opportunities to integrate recommendations from the Plan.



Leaving or establishing natural buffer zones along the stream are a good way to avoid erosion problems. The 2008 Aux Sable Creek Watershed Management Plan recommends filter strips a minimum of 50 feet wide (from the edge of the bank) be created or protected along the streams in the watershed, in agricultural areas.  This may not always be possible, but it can be a goal. 

Another area that can be addressed in order to avoid streambank erosion is to limit cattle access to the stream.  Unlimited access permits trampling and grazing of streambanks throughout the property.  This leads to unstable streambanks and thus, erosion.  A designated crossing point avoids erosion throughout the area and allows cost-effective implementation of best management practices at that specific location, which are planned to prevent erosion.

The Kendall and Grundy County Soil and Water Conservation Districts have cost-share programs in agricultural areas to help address some of the streambank erosion aspects mentioned above. 



Erosion along streambanks or ponds is a common issue.