Why is the Program needed:
Changing land use, channelization (straightening), and the
removal of trees alongside streams have caused drastic changes in
streams and rivers in the watershed.
These
disturbances have increased the volume and velocity of runoff which in
turn causes stream beds to erode and become deeply incised into the
surrounding floodplain.
As streams become deeper, streambanks become more and more vertical and unstable.
The weakened
banks become undercut and slump under their own weight while floodwaters
carry away loosened, unprotected materials and sections of the banks. This destroys
valuable farmland and sends massive quantities of soil into downstream lakes.
Heavy sediment loads in streams and lakes negatively impacts aquatic species, and the deeply incised streams become disconnected
from the adjoining floodplain which aggravates flooding and negatively
impacts groundwater.
Eroding
banks along streams in the Delaware River Watershed contribute to the sedimentation of lakes in the watershed. Eroded soil from streambanks is carried downstream where it is deposited in lakes and ponds and reducing the water-holding capacity. This decreases water
supplies, negatively affects recreation and decreases water quality. Other pollutants (examples: some pesticides, phosphorus and others) can also be transported into lakes attached to these soil particles.
Positive outcomes of the stabilization program:
*Reduces streambank erosion
*Prevents loss of valuable farmland
*Reduces sedimentation of downstream lakes and maintains lake water storage capacity for future water users
*Protects recreational resources
*Reduces negative impact of sediment on aquatic species
*Reduces stream channel degradation which helps maintain groundwater levels
*Restores riparian forest resources and benefits wildlife
*Reduces pollution from other soil-attached pollutants
What practices are being used to stabilize streambanks:
The magnitude of the problem and size of the Delaware River requires a combination
of engineered practices (requiring the use of heavy earth-moving
equipment) and biological components (such as planting native grass and
trees and installing willow poles).
The following practices are components of most projects:
- Reshaping vertical streambanks to a gentler slope which allows for the re-establishment of vegetation on the channel bank.
- Planting of native grasses and trees on the re-shaped channel bank.
- Installation of protective rock at the base (or toe) of the streambank.
- Installation of re-directive rock structures such as rock vanes
or weirs within the stream channel to re-direct the force of stream
currents.
- Planting a riparian buffer on the floodplain adjacent to the
stabilization project. Buffers planted are a minimum of 66’ wide
and extend the entire length of the stabilization project.
Funding Sources:
The stabilization projects funded through the Delaware River
Streambank Restoration Program are large, requiring funding and technical assistance from a combination of
several sources.
Sources of funding and technical assistance to date include the following:
*2009 American Recovery and Restoration Act (ARRA)
*Kansas Water Pollution Control Revolving Loan Fund (KWPCRF) through the Kansas Dept. of Health & Environment
*Kansas Water Office
*Kansas Dept. of Agriculture, Division of Conservation
*Kansas Forest Service
*Individual Landowners
*Private Engineering and Design Firms
*Delaware River WRAPS and its sponsoring agency, Glacial Hills Resource Conservation & Development Region, Inc.