Featured Project: Gordon Creek Stream Restoration

The Gordon Creek Stream Restoration Project was completed in 2015 and minor repairs took place in 2016.  Gordon Creek is a perennial spring-fed stream that was ditched and straightened in the past to facilitate haying of the wet and sub-irrigated meadows.  The ranchers did not know at the time that the ditching and straightening of the stream would, over time, cause the stream to flow faster and cut down in the sand.  Over decades, the water level of the stream lowered which also lowered the water table on the associated meadows.  As that water table lowered, the plants growing on the meadow were no longer sub-irrigated.  The stream banks also became very steep and they sloughed off regularly.  Here is a photo taken before the restoration took place.

Gordon Creek before stream restoration project

The objective of this project was to restore the natural hydrology to a 3-mile section of Gordon Creek, a perennial flowing stream, and 422 acres of the associated wetlands and wet meadows.  The hydrological restoration included reconnecting the stream to the historic floodplain, thereby restoring the water table level, providing aquatic passage, and increasing the quality and quantity of wetland stream habitat for federal trust species including long-billed curlew, trumpeter swan, whooping crane, American burying beetle, and Topeka shiner.

Gordon Creek (same area of stream as Before photo above) immediately after stream restoration
Installing Flex-i-mat structure

The project was designed by local Natural Resources Conservation Service engineers and the design included filling portions of the incised, existing ditched channel to an elevation consistent with the top of the channel.  The material needed to fill the channel came from a nearby upland site and was deposited into the incised channel.  As a result, the current flow was re-directed into an abandoned remnant channel which was at the elevation of the existing wet meadow.  Much of the abandoned remnant channel existed with the proper dimensions, pattern and profile the historic stream utilized.  In certain locations, the remnant chan

Flow through structure used to raise water level while still providing aquatic passage

nel needed to be excavated to the proper slope, profile, and channel dimensions.  Constructed portions of the remnant channel were built to handle base flows, and higher flows will be able to access the functional floodplain.  On the extreme downstream end of the project, two low level grade stabilization structures were constructed in the existing ditched channel.  The structures are a wide overflow type structure that holds a permanent elevation for the entire upstream length of the project.

 

Willows and false indigo were transplanted to a couple areas along the restored stream to prevent excessive erosion.  The transplants were cut from local plants and staked in the ground in the spring of 2017.

 

Construction Specifications:

  • Intermittently restore and construct 21,150 feet of stream channel.
  • Contour and shape 3.2 acres of entrenched stream channel.
  • Install 4,224 square foot of tied concrete block mat (flexamat).
  • Install 733 square yards of permanent turf reinforcing mat.
    Before stream restoration

    After stream restoration

 

 

 

 

 

This project was made possible by all the entities and individuals that worked in partnership to provide financial assistance, technical assistance, and monitoring.  The landowner was an integral partner.  Other organizations that worked with the Sandhills Task Force included, Nebraska Game and Parks Commission, US Fish and Wildlife Service Partners Program, Nebraska Environmental Trust, National Fish and Wildlife Foundation, Natural Resources Conservation Service.