FLOODS and DREDGING

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FLOODS and DREDGING

• West Virginia Council
• of Trout Unlimited
• November 2007

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TU

• Purpose Conserve, Protect and Restore Trout
  Streams and their watersheds in West Virginia

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TU

• 1700 Members
• 8 Active Chapters

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Floods have always been with us!
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In WV homes, towns, businesses, roads, railroads,
schools, etc. were built on floodplains.
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Major Floods in WV

• November 5-7, 1985 Flood
• Many streams in the eastern-central region of WV
  flooded at this time
• The Potomac River Crested at 54 ft. at Paw Paw,
  WV 29 Ft. above flood stage
• 38 people died
• 4,400 homes destroyed

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From Killing Waters by Teets and Young 1986
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Houses from Brushy Run of Seneca Creek 1985
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Southern WV Flood

• July 8, 2001
• 2 deaths
• Many homes, bridges, schools, roads and other
  structures damaged
• Major damage to many streams

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Buffalo Creek 9-9-01
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Buffalo Creek 9-9-01
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Buffalo Creek 9-9-01
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Laurel-Quinnimont Rt. 41 9-4-01
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McDowell County Flood

• May 1, 2002
• 7 Deaths
• Major damage to roads, bridges, schools and other
  structures
• Tug Fork at Williamson crested at 42 ft. which
  was 15 ft. above flood stage

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Elkhorn Creek Kyle 5-15-02
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Elkhorn Creek - Keystone 5-15-02
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Elkhorn Creek Elkhorn Inn 5-15-02
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Elkhorn Creek Kimball 5-15-02
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Frequency of major floods in WV appears to have
increased.
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Impact of floods on trout streams

• Can remove trees from stream banks
• Severe bank erosion
• Rearrange the stream structure
• Can wipe out reproduction and reduce the
  population of adult trout in extreme cases
  (Buffalo Creek - 2001 Flood)

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Native Brook Trout Buffalo Creek9-28-05
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Natural Factors Affecting Flooding

• Amount and intensity of rainfall is 1
• Vegetative cover (impacted by man)
• Time of year (trees intercept and take up a lot
  of water during the growing season)
• Degree of ground saturation
• Type of soil
• Amount of snow and ice on the ground
• Steepness of the terrain

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Man Made Factors Affecting Flooding

• Amount of the watershed covered by buildings or
  pavement
• Extent of paved and unpaved roads in the
  watershed
• Amount of land disturbed by mining, gas well
  drilling, construction, etc
• Timbering practices
• Farming practices
• Floatable objects in the floodplain
• Amount of previous dredging (channelization)

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Dredging after floods

• The stream behind my house needs to be
  dredged.

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Dredging after floods

• Who may be involved?
• An individual or a group of local residents
• Governmental agencies
• National Guard
• Private corporations

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Rich Creek at Jodie 8-10-04
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Barkers Creek 10-28-07
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Barkers Creek 10-28-07
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Glen Fork, Wyoming County July 2001
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Peachtree Creek, Raleigh CountyJuly 2001
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WVDOH dredges at bridges and along roads.
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Norfolk Southern RR dredges at their bridges on
Elkhorn Creek.
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Elkhorn Creek-Northfork 8-30-04
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Most of the dredging that takes place after
flooding is supported by public funds.
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Confusing phrases used to describe dredging
include

• emergency watershed protection
• channel restoration
• stream rehabilitation
• stream stabilization
• stream cleaning
• flood protection

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Stream is usually

• Widened
• Straightened
• Channel deepened
• Trees and boulders removed from the stream
• Often trees and other vegetation removed from the
  stream banks

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Elkhorn Creek Kimball 8-16-02
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Elkhorn Creek Kimball 8-16-02
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Elkhorn Creek, Kimball 8-16-02
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Wind up with unnatural stream channel!
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Elkhorn Creek Keystone 8-16-02
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Dredging increases rather than decreases future
flooding problems

• Greater bank erosion
• Increased sedimentation
• Channel down-cutting or channel filling
• Leads to greater flood damage downstream

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No help during a major flood!
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A dike (berm, levee, flood wall, etc.) can help
protect a specific area, but results in increased
flooding problems downstream.
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(No Transcript)
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Flood Thy Neighbor

• Dredging, straightening the channel, building
  levees, and related activities will lead to
  greater flood damage for your downstream
  neighbors!

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Impacts on fish and wildlife
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Impacts on fish and wildlife

• Eliminates hiding places for fish
• Reduced fish and wildlife populations
• Increase in water temperature due to wide channel
  and removal of shade trees
• Reduced food supply for fish and other aquatic
  life due to removal of streamside vegetation
• Reduced food supply in the stream due to the
  removal of woody debris

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Projects to reduce flood problems

• Plant native trees and other native vegetation on
  bare stream banks
• All bare areas should be mulched and seeded
• Natural Stream Restoration projects can help
  restore stream stability and reduce bank erosion
• Provide financial help for folks willing to move
  out of the floodplain

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Trees are important!-Absorb large amounts of
water-Slow runoff from the land-Prevent stream
bank erosion-Reduce the force of flowing water
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Natural Stream Restoration ProjectsDeveloped by
Dave Rosgen and others.
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Tucker County, WV Wolf Run
Horseshoe Run
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Horseshoe Run Wolf Run
Looking Upstream
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Rock Vane Using Large Boulders
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Root Wad Tree Vane
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Series of Structures
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Horseshoe Run Rock Vanes
Reduce Bank Erosion
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Permits required for working in a stream

• Section 404 Permit from US Army Corps of
  Engineers (USACE)
• Section 401 certification from WVDEP
• WV Public Lands Corporation Permit

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USACE Nationwide Permit allows WVCA to conduct
emergency stream work when there is an Exigency
situation
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Exigency

• Merriam-Webster a state of affairs that makes
  urgent demands
• A situation where action is required to prevent
  loss of life or property.

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Unfortunately, most of the rules are thrown out
the window when an Exigency has been declared.
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Some dredging is necessary to remove obstructions
at bridges and to remove unnatural dams formed by
debris moved by the flood.
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Most dredging is a waste of money!!
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Because dredging

• Destroys the natural stream
• Is an expensive, temporary fix that must be
  maintained
• Increases erosion which leads to more dredging
• Leads to increased flooding problems in the
  future