There are many river users and functions to consider. The current proposed design calls for removing the East side of the Sixth Street Dam completely to provide improved passage for fish and other creatures. The West side of the Sixth Street Dam could be lowered by 30% and encased in boulders to create a scenic waterfall or be removed completely. Our design engineers from River Restoration are still determining the best method to restore the historic rapids while allowing the most benefit for all river users.
All of the dams will be functionally removed from the river, there will be no impoundment, riverwide hydraulic features and no cascading dam face. Physically, proportions of the concrete from the dams may remain in the river as full and foundation support for the boulder grade control and at the abutments near the flood walls. The 6th Street Dam face is currently visible inside the fish ladder by no longer functions as a dam. Any remaining concrete will no longer be required for structural support and most of it will be incased and hidden in the boulder cobble matrix.