1. Project Name:  Dry Creek/Lower Valley Ditch Passage

2. Applicant:

Lower Valley Ditch Company
Elwayne Henderson

Grande Ronde Model Watershed Foundation
10901 Island  Ave.
La Grande, OR 97850

3. Participating Landowner(s) and Agencies:
Lower Valley Ditch Company
Grande Ronde Model Watershed Foundation (GRMWF)
Bureau of Reclamation (BOR)

4. Project Contact(s):
Lower Valley Ditch Company - Elwayne Henderson
Bureau of Reclamation - Darrell Dyke
Lyle Kuchenbecker - GRMWP

5. Project Location:
T. 2N, R. 42E. SW ¼ of Sec 27
Intersection of Dry Creek and Lower Valley Ditch

6. Project Objectives:

The overall goal of the project is to improve native rainbow and anadromous Snake River steelhead production in the Dry Creek watershed, a tributary to the Wallowa River.

Specific objectives are:
§ Eliminate fish access to the Lower Valley Ditch system (reduce potential mortality)
§ Improve year-around juvenile fish passage in Dry Creek through the ditch crossing site.
§ Reduce flooding impact of high water events caused by collection of water in the ditch.
§ Meet Lower Valley Ditch irrigators land management objectives

This project will eliminate adult and juvenile steelhead and rainbow access from Dry Creek to the Lower Valley Ditch.  Juvenile progeny of adults that have spawned in the ditch, or juveniles from Dry Creek that get into the ditch, are at increased risk due to fluctuating ditch flows and the potential for being diverted into fields.

Management Plans/Assessment pertinent to the area:
§ Grande Ronde Model Watershed Action Plan (GRMWP 1994)
§ Wallowa County - Nez Perce Salmon Habitat Recovery Plan (September 1999)

Neither of the above listed assessments specifically address the Dry Creek system.  Both did not cover, in detail smaller tributaries such as Dry Creek.  However, these assessments do identify fish passage and irrigation diversion screening in a general manner as being watershed and fish issues in this reach of the Wallowa River.

The Salmon Plan, Wallowa River - Spring Creek to Head of Wallowa Canyon, p. 109 under Physical Barriers (Study) states "Modify diversion barriers to better provide passage".  Under Diversion Screening (Medium) the plan states "Make sure irrigation diversions and returns are screened, monitored and maintained".

7. Project Description

Introduction
The project will construct a siphon bypass under the Dry Creek Channel for the Lower Valley Ditch.  This will include a concrete intake, with headgate, a 36" PVC siphon pipe, a concrete outlet structure and a PVC drain pipe to dewater the siphon during periods of non-use.  A wastewater bypass will be constructed from the ditch to Dry Creek to handle excess ditch water collected by the ditch during periods of high run-off.  The existing concrete diversion structure will be removed necessitating the construction of three rock vortex weirs to stabilize the Dry Creek channel.  The siphon cannot be operated outside the normal irrigation system (freezing) so alternative stockwater sources will be developed for three landowners on the west side of Dry Creek.  

Existing condition
Dry Creek is a tributary of the Wallowa River and supports resident rainbow and steelhead populations.  The number of steelhead spawners and the level of juvenile fish production are not known.  There have been numerous previous restoration projects on Dry Creek including CREP fencing, off-stream livestock water development and roadwork.  These projects along with modified management practices have resulted in improving watershed and habitat conditions in the Dry Creek system.

The Lower Valley Ditch diverts water from the Wallowa River from a diversion point located in T.1N, R. 42E., NW ¼ of Sec 11. The ditch runs approximately three miles before intersecting Dry Creek.  The irrigation season is May 1 to September 30.  Additionally most irrigation water rights also include .01 cfs stock water rights.  Stock water is usually diverted throughout the year.  The fish screen at the Wallowa River diversion point is not operational during cold weather periods.  

A concrete structure (see attached pictures) has been in place at the intersection of the ditch and Dry Creek for many years.  The structure uses stop boards to check up water sufficiently to allow water to pass through Dry Creek and into the ditch beyond the creek.  The concrete structure constricts the channel to about 15 feet.  The stop boards remain in-place throughout the irrigation season but are removed over the winter.  Minimal stock water flows down the ditch, through Dry Creek and beyond through the winter.  The channel constriction is contributing to bedload deposition above the structure and has likely caused channel scouring below the structure.

The system as it is operated allows the mixing of Lower Valley Ditch and Dry Creek water and consequently allows fish access from Dry Creek into the ditch.  There have been reports of adult steelhead spawning in the ditch.  Juvenile steelhead also have access to the ditch both from upstream and downstream reaches of Dry Creek.  The extent of adult and juvenile use of the ditch is not known.  Juvenile fish in the ditch are at risk of being diverted onto irrigated fields or dewatering of the ditch, or mortality during ditch maintenance activities.  Additionally the stop boards, when in place in the existing concrete structure, are a passage barrier to juvenile fish.

Specific Actions
The project plan includes the following activities:
§ Removal of the existing concrete diversion structure.
§ Construction of a 36" 100 feet long siphon ditch bypass under Dry Creek.  The siphon system includes a concrete inlet structure with trash rack and headgate,                  and a concrete outlet structure.  A PVC drain/cleanout pipe with headgate will be installed running from the bottom of the siphon draining into Dry Creek.  
§ Installation of two rock vortex weirs, one at the approximate location of the existing concrete structure and one each above and below the structure.  The                  vortex weirs will provide vertical streambead stability and prevent a headcut from moving upstream after the existing concrete structure is removed.
§ Construction of a ditch bypass system with concrete inlet structure, including a headgate.  The bypass system will allow excess ditch water an escape route for                  overland flow that can accumulate in the ditch during rain-on-snow or other peak events.
§ Installation of stockwater systems for three parcels on the west side of the road to provide winter stockwater (tank and water lines).
§ Revegetation with native shrub and tree species as needed in the Dry Creek channel immediately above and below the construction site.  Disturbed ground will                  be seeded to reduce noxious weed invasion.  

Construction activities will occur during the in-water work window, July 15 - August 15.  Dry Creek does not flow during this period so water diversion for Dry Creek will not be necessary.  A temporary bypass ditch will be constructed immediately above the construction site to provide continual flow of irrigation water to the lower end of the ditch.

The siphon system will be operated continuously during the irrigation season.  At the end of the season the siphon headgate will be closed.  The siphon drain will be opened to prevent water from accumulating and damaging the siphon pipe.  Stockwater will be available to lower Dry Creek via the siphon bypass.  

Benefits
The overall benefit of the project will be to improve native rainbow and anadromous Snake River steelhead production in Dry Creek.  Specific benefits will be:
§ Eliminate fish access to the Lower Valley Ditch system (reduce potential mortality)
§ Improve year-around juvenile fish passage in Dry Creek through the ditch crossing site.
§ Reduce flooding in the portion of the ditch beyond Dry Creek.
§ Eliminate the potential for future regulatory action associated with the operation of the Lower Valley Ditch at the Dry Creek site.

Project Maintenance
The Lower Valley Ditch Company will manage water distribution in the ditch and will operate the siphon and associated facilities.  The siphon will be dewatered at the end of the annual irrigation season.

Permits
The project will require COE/DSL permit and ESA consultation with NOAA and USFWS.  Both will be facilitated by the GRMWF.

Monitoring Plan/Reporting
The GRMWF will complete a project completion report and monitoring reports in accordance with BPA and GRMWP reporting requirements.    The completion report will be submitted to BPA within 30 days of the end of the contract period.  A monitoring report will be submitted at the end of the first full year and third year of operation.  The following will be assessed/monitored:
§ Monitoring and control of noxious weeds (Lower Valley Ditch Company)
§ Revegetation survival/success (GRMWF)
§ Operation of the siphon and wastewater bypass (Lower Valley Ditch Company/GRMWF)
§ Vortex rock weirs (streambed downcutting and bank erosion (GRMWF)

Work Dates
Construction activities are scheduled for the in-water work window, 2005.