Lewis & Clark Conservation District

Local Common Sense Conservation

Stream Project-Planning Considerations

PROJECT PLANNING

When the Lewis & Clark Conservation District reviews 310 permit applications, we are required to consider the following factors:

Erosion and Sedimentation

Supervisors have to look at the potential effects of the project on erosion and sedimentation, considering the methods available to complete the project and the nature and economics of various alternatives.

Stream Channel Alteration

Supervisors must review the effects of stream channel alterations to minimize adverse impacts and maintain the integrity and function of the natural channel.

Streamflow, Turbidity and Water Quality

Projects must keep impacts to water quality to a minimum, including potential effects of project materials used or removal of ground cover.

Effects on Fish and Aquatic Habitat

Projects must minimize adverse effects to fish and aquatic habitat.  This includes criteria such as fish passage and bank/streambed alterations that impair resource values.

Avoid Harmful Flooding or Erosion

Projects must avoid creating harmful flooding or erosion upstream or downstream.

Minimize Vegetation Disturbance, Protect Existing Vegetation, Control Weeds

Projects should seek to preserve, establish, or enhance native vegetation on the banks and floodplain.

The Conservation District will consider whether there are modifications or alternative solutions that are reasonably practical that would reduce disturbance to the stream and its environment and better accomplish the goals of the project.

Considerations When Planning Your Project

Streams and rivers are complex systems and constantly undergo change.  Their function is primarily to move water and sediment from the upstream watershed to points downstream.  This may seem like a simple function, but the processes that the systems experience can be complex.  There is a perpetual change to systems called dynamic equilibrium.

To determine the cause and effect of channel changes, it’s important to understand the processes that govern stream systems.  Projects need to be designed to work with the natural stream processes to maintain or improve balance in the system.  Adequate project designs increase the potential for long-term benefits to the stream and to landowners. It is important to understand the limitations and the possible outcomes of different types of projects that a landowner may want to do on their property.

Landowners should keep in mind that sometimes the best project is actually to do nothing at all.

For more information on Stream Form and Function, including discussions on stream morphology, stream processes and more, please refer to the Montana Stream Permitting:  A Guide for Conservation District Supervisors and Others. This guide discusses the various permits and permitting agencies in Montana, as well as:

  • Watersheds
  • Geology and Climate
  • Stream Channel Form
  • Bank and Channel Stability
  • Flow Characteristics
  • Field Indicators of Bankfull Flow
  • Channel Downcutting & Re-establishment of Equilibrium
  • Channel Migration Zones
  • Meander Movement and Bank Erosion
  • Role of Large Woody Debris
  • Role of Beaver Dams
  • And a Case Study of Big Spring Creek near Lewistown, Montana