Calaveras River / Budiselich Flashboard Dam Fish Passage Improvement
Budiselich Flashboard Dam is located within the Stockton Diverting Canal, just upstream of the Highway 99 Bridge on the eastern boundary of the City of Stockton (see map (PDF, 96KB)). The dam is composed of a 12-feet-wide flat concrete foundation spanning 98 feet between concrete abutments. During the irrigation season, flashboards are installed to impound water.
The project consisted of alterations to the channel downstream of the dam’s foundation, which was designed to allow fall-run Chinook salmon and steelhead to easily migrate upstream. The design (PDF, 5.6 MB) is comprised of 7 arched boulder weirs buried in engineered streambed material (cobbles, gravel, sand, and silt), creating a rock ramp roughened channel. The rock ramp has a 10-feet-wide low-flow channel and a 3 percent longitudinal gradient, which is a milder slope than the pre-project channel, creating lower velocities, and less turbulence in the channel. It also provides enough water depth allowing fish to navigate more easily upstream of the project site. The project extends 250 feet downstream of the foundation and has a maximum width of about 125 feet. The project was designed to meet regulatory agency criteria at all flows greater than 30 cubic feet per second (cfs). After the project was completed, fish were seen moving upstream in the low-flow channel and approximately 400 adult fall-run salmon were estimated to have passed the project site in late 2011.
In 2013, the project received a Distinguished Project Award (Honorable Mention) from the American Society of Civil Engineers, Environmental and Water Resources Institute /American Fisheries Society, Bioengineering Section Joint Committee on Fisheries Engineering and Science.
Is this an Active Project or Completed Project? Completed
Is this an Ecorestore Project? No
Watershed: Calaveras River
Public Access: No
Prior to improvement, the dam was a significant fish passage barrier, voted as the top priority for remediation by the Calaveras Fish Group. The foundation is elevated approximately 7 feet above the downstream channel bottom. Before remediation, the steep downstream face of the dam was protected from scour by piles of broken concrete rubble and rock riprap extending about 100 feet downstream of the structure.
The goal of the project was to improve fish passage at the dam by meeting the regulatory fish passage criteria for adult salmonids and by meeting restrictions on water surface elevations to prevent flooding.
We provided topographic surveying, engineering design, hydraulic modeling, construction oversight and staking, and hydraulic monitoring for the project. The hydraulic modeling ensured that this project has no significant impact on water surface elevations for either the 100-year or 200-year flows in the Stockton Diverting Canal.
In 2001, modifications were performed to temporarily improve fish passage conditions at Budiselich Dam, using sandbags to create a flow path for migrating salmonids.
In 2004, we studied and assessed the hydraulic conditions at the dam and concluded that it was a temporal barrier for both adult and juvenile salmonid passage, requiring at least 200 cubic feet per second (cfs) to meet regulatory fish passage criteria for adult anadromous salmonids. The results of this assessment are presented in the 2007 Calaveras River Fish Migration Barriers Assessment Report.
The project was designed by our engineers and was constructed in September 2011.
Our funding for this project came from Ecosystem Restoration Program. Funding for the project was also provided by SEWD, USFWS, DFW, and the National Fish and Wildlife Foundation.
The project was a joint effort between us, Stockton East Water District (SEWD), the U.S. Fish and Wildlife Service (USFWS), the California Department of Fish and Wildlife (DFW), and the National Fish and Wildlife Foundation. SEWD provided coordination, engineering work, administration, environmental permitting, and project construction. The support for this project has come from the Calaveras River Fish Group (CRFG), which is made up of interested stakeholders representing both governmental and non-governmental entities. USFWS coordinates the CRFG, and were instrumental in getting the project completed. DFW provided engineering design assistance. The project was endorsed by SEWD's agricultural customers and urban contractors and was approved by numerous regulatory agencies.
For more information, view the 2012 Salmonid Restoration Federation Fish Passage and Protection Workshop Presentation (PDF, 14 MB).
Publications & Reports
- 2012 Salmonid Restoration Federation Fish Passage and Protection Workshop Presentation
- Budiselich Flashboard Dam Fish Passage Improvement Project – Design Drawings