North Unit begins headworks renovation on $11 million gate, fish screen in Bend
By Michael Kohn
North Unit Irrigation District has ended its water deliveries for the season and started work on installing a new $11 million headgate and fish screen on its main canal. The work will close a section of Division Street until April.
The previous headgate and fish screen had been in use for 80 years. Following the Oct. 9 shutdown, contractor HP Civil began removing the existing superstructure and fish screens.
Earlier this week, divers arrived at the site to remove debris from the former fish screen guide slots and prepare for installation of permanent concrete bulkheads. Crews also began installing temporary bulkheads as part of the preparations for dewatering the work area.
Once the bulkheads are in place and dewatering is complete, HP Civil will begin demolishing the western retaining wall.
The project includes replacing the existing fish screens and modifying portions of the headworks to improve operations and fish protection along the Deschutes River.
The main purpose of the new facility is to keep fish out of the canals, but the screens also help with water efficiency and management by reducing the amount of debris and sediment that can clog or enter the canal system.
The new facility will feature a vertical flat-plate screening system with an automated cleaning mechanism that moves a brush along the screens to remove debris. The design will funnel fish to a single bypass point, returning them safely to the river downstream of the diversion.
The current screens, which date back to the early years of the irrigation project, are nearing the end of their usable life after roughly 80 years of continuous operation.
Planning, permitting and funding efforts for the project have been underway for nearly 20 years. The district has received a $5.9 million grant from the U.S. Bureau of Reclamation to help fund the improvements.
The project will replace a fish screen system that has been in use since the end of World War II. The new, self-cleaning screens are designed to improve water efficiency and reduce debris buildup in the canal system.
Photo: A construction crew with HP Civil Inc. works to remove the fish screens at the North Unit Irrigation District diversion on the Deschutes River in Bend on Oct. 9. (Dean Guernsey/The Bulletin)
