Central California Traction Company Railroad Bridge
Fish Passage Improvement Project


Name of Project: Central California Traction Company Railroad Bridge Fish Passage Improvement Project

Location of Project: The project area is located at about 37.9881, -121.2657. This location is the railroad crossing over the Stockton Diverting Canal; however, the work will be conducted immediately upstream (upstream extend to about 50 feet) and downstream (extent to about 250 feet) of this railroad crossing.


Description of Project: This project includes the Stockton East Water District (SEWD), the United States Fish and Wildlife Service (USFWS), and California Department of Water Resources (CDWR) to improve upstream and downstream fish passage at the Central California Traction Railroad Crossing (CCTRC) on the Stockton Diverting Canal at river mile 1 for migratory adult and juvenile fish species. These species include the federally threatened Central Valley steelhead (Oncorhynchus mykiss) and the species of concern, fall-run Chinook salmon (Oncorhynchus tshawytscha). Previous to this proposal, all three parties successfully implemented fish passage improvements at the Budiselich Flashboard Dam (river mile 2) on the Stockton Diverting Canal and at the Caprini Low Flow Crossing (river mile 7.3) on Mormon Slough. These locations, in addition to the CCTRC, were identified by CDWR as priority locations of fish passage impediments (2007). In an effort to continue to address fish passage impediments in the Stockton Diverting Canal and Mormon Slough, the SEWD (in collaboration with other agencies) request additional funding through this proposal. Funds will supplement in-kind contributions to help acquire construction materials, secure any additional services necessary, and ensure timely completion of the project. 


The CCTRC is located within the primary migratory route for fish species and is a temporal barrier or discharge dependent barrier to migrating fish. Currently, the CCTRC presents a significant barrier to fish migration for adults of both species at discharges less than 210 cfs due to the shallow water depth downstream of the crossing and across the apron weir (CDWR 2007). It also presents passage problems for juvenile salmonids when discharge is less than 11 cfs (CDWR 2007). According to HEC-RAS modeling conducted by CDWR (2007), the CCTRC provides unimpaired passage 5% of the time for adult Chinook salmon, 18% of the time for adult steelhead/rainbow trout, and 46% of the time for juvenile salmonids. The proposed design for fish passage improvement consists of modifying channel bed morphology by creating a ramped stream channel through installation of several grade control boulder weirs (CDWR 2012). These improvements will concentrate flows into a low flow channel downstream, help meet passage depth and velocity criteria, and allow for improved passage at discharge as low as 30 cfs. Alleviating passage issues at CCTRC will provide improved access to upstream optimal spawning and rearing habitat upstream of Bellota Weir for both Chinook salmon and Central Valley steelhead (Stillwater Sciences 2004). Additionally, this project will provide a more favorable downstream migration corridor for juvenile salmonids. Improving upstream and downstream migration through this area will also bolster the effects of the upstream projects (i.e., Budiselich and Caprini Projects), allowing fishes to have increased accessibility upstream and downstream through these improved areas. To date, CDWR has identified passage issues at the CCTRC and developed a preliminary design (CDWR 2012) for construction of several boulder weirs to help address fish passage impediments. 


Description of why this barrier is a high priority project: This project is endorsed by numerous agencies.


The name(s) of the recovery plans and the specific task that name this barrier as a high priority: The California Department of Water Resources identified this structure as an impediment to migratory fish species in the Calaveras River Fish Migration Barriers Assessment Report (2007). Stockton East Water District, the United States Fish and Wildlife Service, and the California Department of Water Resources endorse this project as a high priority. Stockton East Water District has been working with USFWS (Donald Ratcliff) and CDWR (Randy Beckwith) to see these fish passage projects to completion. Currently two projects have successfully reduce minimum fish passage flow requirements from over 700 cfs down to 30 cfs. This current project is the next upstream location to be modified to allow for minimum passage flows of 30 cfs. Both Donald and Randy are listed as
key project members below as well.


The California Fish Passage Forum has nine overall objectives. This project will help to address: 1) Remediate barriers to effective fish migration.3) Identify, assess and prioritize the removal of fish passage barriers. 9) Implement education and outreach activities, targeting both the general public and fish passage practitioners.


Anadromous fish species that benefit from this project: Chinook salmon, steelhead/rainbow trout


Miles of stream opened as a result of project implementation: 13.4 miles.


Location and distance in stream miles to downstream river structures, and whether each structure represents an insignificant, partial, or total barrier to fish passage: According to CDWR (2007), the structures downstream of the project area on the Stockton Diverting Canal are Wilson Way Bridge and Wooden Bridge West of Wilson Way, which are both located at river mile 0.8 (0.2 miles downstream of the project). These locations were not identified as impediments to migration (CDWR 2007). The Wooden Bridge was removed in 2006, after the assessment was completed.


Location and distance in stream miles to upstream river structures, and whether each structure represents an insignificant, partial or total barrier to fish passage: Currently, two upstream passage improvement projects have been completed: Budiselich Dam (river mile 2 on the Stockton Diverting Canal) and Caprini Low-Flow Crossing (river mile 7.3 on Mormon Slough). Budiselich Dam is 1.0 mile upstream of the project area, and the Caprini Low-Flow Crossing is approximately 6.3 river miles upstream. These two areas now allow passage of Chinook salmon and steelhead/rainbow trout and are no longer significant barriers to fish passage. Upstream of these two projects are Hosie Low-Flow Crossing (river mile 13.4) and Watkins Low-Flow Crossing (river mile 16.9), which are both on Mormon Slough (see attached map figures). Hosie Low-Flow Road is approximately 12.4 miles upstream of the project area and Watkins Low-Flow Road Crossing is approximately 15.9 river miles upstream of the area. Both Hosie Low-Flow Crossing and Watkins Low-Flow Crossing present partial, but significant barriers to fish. Hosie provides unimpaired passage for adult Chinook salmon 3% of the time, 14% of the time for adult steelhead/rainbow trout, and 30% of the time for juvenile salmonids (CDWR 2007). Watkins provides unimpaired passage or adult Chinook salmon 5% of the time, 27% of the time for adult steelhead/rainbow trout, and 30% of the time for juvenile salmonids (CDWR 2007). Both the Hosie and Watkins Low-Flow Crossings are scheduled to be modified in the near future.


How will the project be evaluated and measured for success: Success will be measured by fisheries life cycle monitoring for Chinook salmon and steelhead/rainbow trout. This can be done through several methods including and not limited to using rotary screw traps to monitor outmigration of juveniles, redd surveys to identify and enumerate spawning fishes, and/or snorkel surveys to identify and enumerate fish species and distribution. Currently, FISHBIO conducts annual fisheries monitoring upstream of Bellota Weir, and this monitoring will continue to provide data on fisheries abundances and passage and will be useful in evaluating the effectiveness of this project.

Project Map - Calaveras


Preliminary Design