O'Shaughnessy Dam instream flow evaluation study plan

As part of the Upper Tuolumne River Ecosystem Project, McBain & Trush have developed a study plan that focuses on our initial objective of developing ecosystem-based instream flow recommendations for O'Shaughnessy Dam. Many aspects of the plan have been underway since the inception of the Ecosystem Project, while others are new and will be implemented through December 2010. In particular, the SFPUC and McBain & Trush have worked closely with the USFWS to develop the flow-habitat relationship studies which are currently underway and will continue into the fall, with followup work in 2010.

Upper Tuolumne River Ecosystem Project: O'Shaughnessy Dam Instream Flow Evaluation Study Plan (PDF | 1.7MB)

UC Davis Extension course: The Tuolumne River - Ecology, Resource Management, and Whitewater

UC Davis Extension is offering a two-day educational rafting trip with field demonstrations and on-river lectures about aquatic and riparian ecology, geology, geomorphology, hydrology, controversial water resource development and the rich human history of the Tuolumne River. See the UC Davis Extension website for more information. Note: currently both classes are full, but wait listing is available.

Upper Tuolumne River Stakeholder Group fall meeting date and time

The next meeting of the Upper Tuolumne River Stakeholder Group is set for November 13, 2009, 11am - 3pm at the Moccasin Administration Building. Stay tuned, we'll provide an update later this year with a proposed agenda and other materials.

Upper Tuolumne River Stakeholder Group meeting

The SFPUC Natural Resources Division and Hetch Hetchy Water and Power Division will host the spring meeting of the Upper Tuolumne River Stakeholder Group in Moccasin on Friday, March 20. The agenda includes a morning session with updates from Yosemite National Park, the Tuolumne River Trust, and SFPUC. Following lunch, Yosemite and SFPUC scientists will discuss ongoing climate change studies being conducted to help understand the potential impacts on management of Yosemite National Park and the Upper Tuolumne watershed. Finally, the SFPUC will provide updates on work in 2009 as part of the Upper Tuolumne River Ecosystem Project.

The meeting will be held in the Moccasin Administration Building, and lunch will be provided by Hetch Hetchy Water and Power. If you plan to attend, please email Bill Sears (wsears@sfwater.org) so we can have enough lunch for all.

Preliminary temperature modeling data assessment report available

An initial report assessing the quality and availability of data needed for water temperature modeling has been completed by SFPUC consultant Merritt Smith Consulting. The findings of the report will be used to build a water temperature model for the Upper Tuolumne River to evaluate the historical stream temperature regime and the effects of future environmental water release recommendations from Hetch Hetchy Project facilities.

Preliminary Analysis of Available Data for Modeling Temperature in the Hetch Hetchy Reach (PDF | 0.7MB)

Sediment supply and transport report available

SFPUC consultants McBain & Trush have produced a preliminary sediment transport report for the Upper Tuolumne River between O'Shaughnessy Dam and Early Intake. The report is a first step towards characterizing the sediment transport dynamics of the upper river and developing a model that can be "gamed" to help assess the effects of future environmental flow recommendations for O'Shaughnessy Dam on sediment dynamics in the river.

Preliminary Sediment Source and Sediment Transport Capacity Evaluation: O’Shaughnessy Dam to Poopenaut Valley (PDF | 1.1MB)