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Westland-Ramos Fish Passage and Habitat
Restoration ProjectBPA Project No. 2002-057-00
September 23, 2004
Westland Irrigation District
Project Area
Project Objectives
Improve upstream passage for ESA-listed steelhead trout and bull trout
Increase sediment transport through reach which will improve channel stability (reduce erosion)
Enhance BPA fish passage investments at Westland Dam
Improve fish habitat and riparian habitat in Westland Ramos project reach.
Retain and improve diversion capacity
Progress to-date
Bedload and hydraulic studies have been completed. 30% design drawings are complete. Have had series of meetings with technical work
group and stakeholders to refine project. Original concept of improvements to Feed Dam have
changed significantly to ensure the project does not change existing operations and increase O&M costs.
Drafted BE and HIP documents.
Fish Passage at Feed Dam
Factors limiting fish passage Fishway HydraulicsFull crest spill at all flowsFalse attraction
Feed Dam Fishway
Hydraulic Drop at inlet to fishway is approx. 4 feet at low flows (160 cfs). Agency criteria is 1 foot.
Feed Dam Fishway
“(The Feed Dam is) the only significant barrier to upstream migrants…under adequate flow conditions.”
“Reconstruction in the form of a full channel fishway or dam removal are likely the best options for upstream migrants at this facility.”
[Contor et al., CTUIR 1997]
100
80
60
40
20
0
1995-96
1994-95
1993-94
Summer Steelhead Mean Passage Times
Spring Chinook Mean Passage Times
1996
1995
1994
Westland
Feed
Stanfield
Bedload Transport Issues Current bedload transport regime
impairs fish habitat through Poor channel form Poor channel stability Degraded riparian area
Findings of Bedload Study
Flows approaching the bankfull stage are required to transport sediment in the study reach.
Modifications to the Westland Dam will increase sediment transport capacity, particularly important for the range of flows within the bankfull, or channel-forming flows.
Findings of Bedload Study
Dam notching will not influence the erosion and deposition characteristics of the river for flows exceeding about 10,000 cfs (6-yr event).
Modifications to Westland Dam are not likely to adversely affect channel form downstream of the dam.
Modifications to Westland Dam will have favorable effects in the reach between the dams by improving capacity to transport sediment within the range of channel-forming flows.
Instream Gravel Maintenance at
Westland Dam
Project Proposal to Enhance Fish Passage at
Feed Dam
Submerge existing fishway using rock weirs downstream of dam
Plan View of Feed Dam Improvements
Example Rock Weir
Example of Rock Weir
Plan View of Westland Dam Improvements
Project Proposal for Westland Dam
Two rubber bladder dams are proposed at Westland Dam to facilitate bedload transport past dam
Project Schedule
Plan and select preferred alternative April 1999 Engineering feasibility January 2000 Sub-basin stakeholder consensus December 2000 Final design and permitting Nov 2003 - October 2004 Implementation July - September 2005 Develop and implement monitoring plan 2004 - ongoing
Expected Results Enhance Fish Passage Eliminate barriers to passage at all flows Minimize migration delays
Improve Bedload Transport Substantially reduce in-channel
maintenance Initiate conditions for channel stability Facilitate riparian recovery Maintain irrigation diversion capacities
Q & A