Fish screens and fish passage were identified in the Walla Walla Subbasin Plan as  critical limiting factors that must be addressed to achieve recovery of ESA-listed Mid-Columbia steelhead and bull trout and ensure the success of reintroduced spring Chinook salmon in the Walla Walla Basin.  Consistent with the recommendations of the Subbasin Plan, Gary James, CTUIR Fisheries Program Manager, proposed under 1996-011-00 the design and construction of adult passage and juvenile screening facilities at the Old Lowden diversion (RM 29.3) and the Bergevin-Williams diversion (RM 31.6), both of which are located on the Walla Walla River.  Project 1996-011-00 was subsequently combined with 2 other capital projects into 2007-396-00.

These diversions have a negative effect on adult anadromous fish passage during the irrigation season when heavy equipment is used to push up temporary gravel dams to divert water from the Walla Walla River into the Old Lowden ditch and Bergevin-Williams ditch for irrigation.  They also have a negative effect on juvenile anadromous fish survival due to the use of non-compliant fish screens.  Potential may exist to consolidate one or both of these diversions with the state-of-the-art Garden City/Lowden 2 diversion (BPA funded project sponsored by CTUIR) which was constructed in 2000.  Work under this contract will include a feasibility study that will allow engineers and stakeholders to develop the best possible conceptual plans for the diversions, completion of engineered plans, specifications and an engineer’s cost estimate as well as acquisition of environmental permits/clearances and construction easements.

It should be noted that WWCCD plans to design pipeline projects for the Old Lowden ditch and the Bergevin-Williams ditch concurrently with this diversion design effort.   Our intention is to conduct the diversion design effort pipeline design effort in parallel as much as possible to ensure compatibility of the two systems.