Wednesday, July 31, 2013
East Fork Irrigation District is in the process of building a new fish ladder and weir near Tollbridge Park.
A wide array of partners have helped EFID with technical assistance and construction funding, including the Oregon Watershed Enhancement Board ($403,360), Confederated Tribes of Warm Springs ($1,675,000) and the Hood River Watershed Group (grant writing and technical assistance).
Since the dramatic February 1996 flood that swept down the Hood River valley, East Fork Irrigation District has been challenged with maintaining and operating its push-up dam and irrigation diversion above Tollbridge Park, near the town of Mount Hood. The near-record flows changed configuration of the upstream channel, making the stream channel less passable for the basin’s critical steelhead and salmon populations.
Local partners got active in 2005 to help EFID assess conditions at the site and begin designing a new diversion structure that would operate more efficiently and provide better fish passage. The partnership, consisting of East Fork Irrigation District, the Confederated Tribes of Warm Springs and Hood River Watershed Group, worked with various agencies to examine alternative diversion designs and accomplish preliminary engineering.
Funding for the engineering and construction design was provided by the Hood River County Title II program and the Confederated Tribes of Warm Springs.
The final design includes a pneumatically operated Obermeyer Weir to replace the existing rock push-up dam. The weir will lie flat against the channel bottom during off-irrigation periods to allow natural river flows.
During the spring and summer, the weir plate will be remotely raised and lowered by inflatable rubber bladders, allowing the diversion amounts to be adjusted for water demand. The design also includes a fish ladder to provide passage around the diversion when it is raised.
Construction of the project is being done by Crestline Construction, based in The Dalles. The company began preparing the site in early June and then started constructing the fish ladder.
EFID General Manager John Buckley said, “This project has been years in coming for EFID and Mt. Hood Irrigation District, and with the help of all our partners, we expect to see benefits for both fish and farming by complying with current fish passage requirements, increasing regulatory certainty, and improving our operational efficiency.” Buckley anticipates the project will be done by fall 2013.