Wednesday, November 27, 2013

Economic Impact of the 2013 Rim Fire on Natural Lands

To support new methods of valuing watersheds and the ecosystem services they provide, the San Francisco Public Utilities Commission funded Earth Economics to develop a preliminary assessment of the economic impact of the Rim Fire. The preliminary assessment includes loss estimates related to air quality, carbon sequestration, flood protection, erosion control, biological control, water filtration, pollination, habitat and biodiversity, property and aesthetic values, and recreational values. This initial effort provides support to federal, state, and local governments in justifying more robust, long-term investments in watersheds and forest health. The assessment is available here.

Tuesday, November 12, 2013

Glen Canyon Dam high flow releases

For over 5 years the SFPUC and NPS have collaborated on experimental flood releases from O'Shaughnessy Dam to support development of a new instream flow management plan for the upper Tuolumne River between the dam and Early Intake.  The releases have primarily been conducted to test flow thresholds for sediment transport and Poopenaut Valley wetland inundation.  Similar flood release experiments have been underway on other rivers; among the most widely reported are the releases from Glen Canyon Dam into the Grand Canyon on the Colorado River.

The Glen Canyon Dam Adaptive Management Program began in 1997 as an effort to use high flow releases to manage sediment (primarily sand) for the benefit of backwater habitats that provide key fish and wildlife habitat, reducing erosion of archaeological sites, restore and enhancing riparian vegetation, and restoring sand bar beaches for recreational boating and camping.  The releases maintain water supply obligations by releasing less water during other parts of the year, mimicking pre-dam flows and water temperatures.

This week, the Glen Canyon program is conducting a second high flow experimental release from Glen Canyon Dam under a protocol approved in 2012. The protocol calls for conducting more frequent high flow experimental releases from the dam timed to occur following sediment inputs to the Colorado River from downstream tributaries. Large amounts of sediment were deposited over the summer due to major rainstorms.  The volume of sediment available is about three times larger than the volume available during the last high flow release in the fall of 2012.

Read more on the 2013 releases from the LA Times and the US Bureau of Reclamation. Also, checkout some of the science and multimedia products the USGS is producing related to the high flow releases.

Friday, November 8, 2013

Re-scheduled fall stakeholder meeting

The re-scheduled fall stakeholder meeting will take place on Friday, November 15, 2013.  Please RSVP ( if you plan to attend.  View the draft agenda here.

Tuesday, October 15, 2013

Postponed: fall stakeholder meeting

Due to the continuing federal shutdown, federal stakeholders and partners will likely be unable to attend or provide updates at the scheduled stakeholder meeting on October 18th.  Given the importance of their participation to UTREP and the interests of upper Tuolumne stakeholders we are rescheduling the stakeholder meeting for November 15th, 2013, pending confirmation with federal agencies.  An update will be provided when the meeting is finalized.

Friday, September 27, 2013

Capturing pre- and post-burn imagery in "gigapixels"

UC Davis has done it again, this time with "gigapixel" imagery of the Clavey River confluence, before and after the Rim Fire.  A gigapixel image contains more than 100 times the information captured by a typical 10 megapixel digital camera.  Gigapixel imagery is a product of NASA, Google, and Carnegie Mellon University efforts to develop imaging technologies for NASA Mars rovers.  The technique has been used in Yosemite Valley to document rockfall hazards, and as UC Davis has illustrated, gigapixel imagery has potential for broad application in watershed and river management to document changing landscapes over time.

Thursday, September 26, 2013

UC Davis travels to the bottom of the Rim Fire

Several UC Davis Center for Watershed Sciences staff received permission from the Stanislaus National Forest to hike into the mainstem Tuolumne River near the Clavey River confluence to investigate the fate of river monitoring gear after the Rim Fire.  Here's what they found.

Tuesday, September 24, 2013

Fall stakeholder meeting

Quick note: the Fall 2013 meeting of the Upper Tuolumne River Stakeholder Group will take place on October 18th in Moccasin.  An agenda is currently being developed.  If you'd like to attend, RSVP to

Wednesday, September 18, 2013

Southern Sierra Fire and Hydroclimate Workshop

The Southern Sierra Fire and Hydroclimate Workshop is scheduled for October 1-4, 2013 at the Yosemite Lodge in Yosemite Valley.  This event combines, for the first time, the annual Yosemite Hydroclimate workshop and the Wildland Fire Science workshop.  The workshop focuses on an integrated view of the physical landscape, climate effects, hydrology, and fire regimes of the Sierra Nevada.   Given the recent Rim Fire, which burned portions of the Stanislaus National Forest and Yosemite National Park, this and future workshops should provide a useful forum for tracking fire science efforts in the coming years.   More information and registration details can be found here.

Friday, August 30, 2013

Rim Fire timelapse

Some incredible videos are coming out of the firefighting efforts on the Rim Fire.  Although most are readily available via Twitter and other social media, we'll be sharing a few that provide some perspective on one of the largest fires in California history.  Here's one from Yosemite National Park.

Monday, August 26, 2013

Rim Fire

The Rim Fire, which began on August 17th near Jawbone Ridge, has now burned through a majority of the UTREP study area.  Firefighting efforts are ongoing; updates can be obtained from Inciweb and CalFire.  Several other resources are available online to track the Rim Fire, including ESRI's Rim Fire map and the KPCC fire tracker, and the Twitter feeds of Yosemite National Park Fire Management and CalFire.

Tuesday, April 30, 2013

The Airborne Snow Observatory Project

LiDAR data from the ASO project
NASA and Cal Tech's Jet Propulsion Laboratory are conducting a pilot project this spring, known as the Airborne Snow Observatory (ASO), to more precisely estimate the volume of water present in the snowpack within the Hetch Hetchy watershed.  The project utilizes frequent aircraft flights and specialized sensors to develop water volume estimates that are potentially more accurate than existing methods, and provide data on a weekly basis versus the existing monthly snow surveys.  The techniques developed in the pilot project may eventually help reservoir operators better manage reservoir operations and UTREP ecological releases.  Read more about the Airborne Snow Observatory Project in this Washington Post articlethis LA Times story, and this KQED radio bit.

Spring stakeholder meeting materials

The agenda and presentations from the April 19th, 2013 Upper Tuolumne River Stakeholder Group meeting are now available online.  The Fall stakeholder meeting is scheduled for October 18, 2013 in Moccasin.

Tuesday, March 19, 2013

Powered paragliding the Tuolumne River Canyon

Pine Mountain Lake resident Rex Pemberton and fellow powered paraglider David Royer take a spectacular low altitude flight down the Tuolumne River canyon.

Monday, March 18, 2013

SFPUC comments on the Draft Tuolumne River Plan

In January, Yosemite National Park released the Tuolumne Wild and Scenic River Comprehensive Management Plan and Draft Environmental Impact Statement (also known as the Tuolumne River Plan or TRP). The TRP describes management alternatives for the Tuolumne River Wild & Scenic river corridor within the park, including portions of the UTREP study downstream of O'Shaughnessy Dam.

The SFPUC has submitted comments to Yosemite National Park regarding the TRP.  SFPUC comments can be viewed or downloaded here.  The comment period closes today, March 18th.

Saturday, February 9, 2013

What is a natural hydrograph?

The pre-development or "natural" state of a river system provides important context for river ecosystem management and rehabilitation: What did the river system look like before major development?  What is the "natural" hydrologic regime?  How are species adapted to the natural hydrograph?  These are all questions that the UTREP is investigating in the upper Tuolumne, and are common to many other river ecosystem management efforts.

On January 18, 2013, the Delta Science Program and the UC Davis Center for Aquatic Biology & Aquaculture (CABA) hosted a seminar to explore how we use, and what we mean by, a natural hydrograph or unimpaired flows.  The seminar focuses on the California Bay-Delta, but is relevant to work on the upper Tuolumne and elsewhere.

Video of the seminar is available on the CABA website.

Tuesday, February 5, 2013

Lyell Glacier in the news

The San Francisco Chronicle reported on the retreat of the Lyell Glacier in Yosemite National Park, at the headwaters of the Tuolumne River.  Recent work by NPS on the rate of retreat was presented at the Fall 2012 meeting of the Upper Tuolumne River Stakeholder Group.

Friday, January 11, 2013

Tuolumne Wild & Scenic River Plan released

Yosemite National Park has released the Tuolumne Wild and Scenic River Comprehensive Management Plan and Draft Environmental Impact Statement (Tuolumne River Plan/DEIS). The plan describes management alternatives (including a preferred alternative) for the Tuolumne River Wild & Scenic river corridor within Yosemite National Park, including portions of the UTREP study area.  Studies by UTREP collaborators, including the NPS Looking Downstream Project efforts, contributed to development of the plan.  The upper Tuolumne River was designated by the U.S. Congress in 1984 under the Wild and Scenic Rivers Act. The park has also released the Merced River Plan, which addresses Wild & Scenic River management within the Merced River corridor, including Yosemite Valley.