West Branch Diversion and Pipeline Design

1) The project is located near the headwater of West Branch Bridge Creek in the Bridge Creek Watershed southwest of Mitchell OR. 2) Currently water is conveyed from West Branch Bridge Creek through a 2.3 miles open hillside ditch to service approximately 250 acres of fields. The ditch experiences water loss and has a high rate of failure from breaching. The diversion which supplies the ditch dewaters a section of West Branch Bridge Creek and is a fish passage barrier. 3) This TA grant will analyze the ditch loss and irrigation layout to develop a conveyance pipe design and identify the amount of water that will be conserved through the piping process. A design will also be developed for the diversion and West Branch Creek which will provide fish passage and return the creek to its historic channel. 4) ODFW and USFWS will be consulted during the design process. The OWRD Grant and Loan program will also be consulted with since the objective of this TA project will be to identify conserved water which can be left instream. This would make the implementation project eligible for OWRD funding. The landowner is very involved in the project and is contributing significant funding.

This Technical Assistance project will analyze the ditch loss and irrigation layout to develop a conveyance pipe design and identify the amount of water that will be conserved through the piping process. A design will also be developed for the diversion on West Branch Creek which will provide fish passage and return the creek to its historic channel. The Council expects to seek implementation funding through the OWRD Water Project Grants and Loans which require at least 25% of conserved water into a permanent instream lease. Restoring fish passage at the diversion is also a goal of the project and will benefit fish instream.