Colorado Avenue Dam Proposed Paddle Trail Improvements
Background
In June 2007 Recreation Engineering and Planning (REP) completed a Paddle Trail Feasibility Study that assessed opportunities for a continuous water trail on the Deschutes River within the boundaries of the Bend Park and Recreation District (BPRD). Safe passage and whitewater play improvements at the Colorado Street Dam were among the top priorities on a list of potential paddle trail improvement projects identified in the study. The Colorado Dam site was identified for a number of reasons including increased river use in the Mill District area, recent accidents and incidents at the dam, the proximity of McKay Park and the potential for significant safety and paddle trail improvements.
In fall 2007, REP was awarded a second contract to provide preliminary engineering for proposed modifications at the dam site that would most effectively meet the safe passage and whitewater play objectives set forth in the Paddle Trail Feasibility Study. Along with the guidance presented in the earlier study, REP considered river flow regimes and made a detailed survey of the river bed and banks at the Colorado Dam site. In addition, the park and recreation district retained Pacific Habitat Services (PHS) to perform a preliminary review of existing environmental conditions and sensitive habitats in the area. REP consulted with PHS to help identify an ecologically sensitive design for the paddle trail improvements under consideration and PHS assessed potential habitat impacts of the proposed modifications.
The information gathered in the REP and PHS studies was used to create three preliminary concepts for paddle trail modifications to the Colorado Street Dam. These concepts were presented to William Smith Properties, the owner of the dam; to the Bend Paddle Trail Alliance; and to the public in January 2008. Following the January meetings and with input from district staff, REP further refined and detailed the conceptual plans to arrive at a draft design report in April 2009.
The draft report and its recommendations were presented to the landowner, the Upper Deschutes Watershed Council, the Bend Paddle Trail Alliance, a group of regulatory agencies and the BPRD board of directors. Based upon those meetings a further revision of the report calling for an additional boater bypass/fish passage only option and other minor revisions to the text have been incorporated into the January 2010 report.
Recommended Option
The January 2010 draft of REP's preliminary engineering report recommends Option 1A which proposes a three channel design. The proposal maintains pond water levels above the dam while modifying the dam structure and the pedestrian bridge that lies on top of it. The solution brings fill material to the base of the dam to step the river bed up providing a boater bypass /fish passage channel, a whitewater play channel, and a habitat protection channel.
The bypass/fish passage channel is adjacent to the McKay Park river bank and provides an evenly graded route for less skilled river users to safely navigate the dam. A narrow vegetated rock island below the dam separates this channel from a whitewater play channel located in the center of the river.
The proposed whitewater channel includes three dynamic "pools and drops" of varying difficultly with the most challenging near the dam spillway and the gentlest at the bottom of the reach. Whitewater boaters can enter this channel from upstream or downstream depending on their desired play style.
A habitat protection area is separated from the whitewater play channel and lies in the right half of the river. The habitat area (channel) remains little disturbed from its present state. It features stream bed gravels suitable for resident trout spawning, calm water areas for aquatic invertebrates, and resting areas for waterfowl and fish. This area will also create a buffer between river users and the existing osprey nesting platform and private property on the right bank.
Next Steps
The January 2010 Colorado Street Dam report was accepted by the BPRD Board of Directors. The recommended improvements are not as yet included in the district's Capital Improvement Plan (CIP). Private fund raising may be a strategy that could result in moving ahead with the proposed paddle trail improvements outlined in the report.
Following an RFP process, the district is currently pursuing a contract with an engineering firm to provide permit ready documents based on the plans developed in the 2010 report. This work will include, more extensive engineering and environmental analysis of the proposed design and additional consultation with regulatory agencies.
If you have any questions or comments on the Colorado Dam Report or its findings contact Chelsea Schneider, Landscape Architect at (541) 706-6155 or chelsea@bendparksandrec.org.
