Lake Oroville Community Update - February 28, 2020

DWR Begins Installation of  New Piezometers at Oroville Dam

Next week DWR will install eight new piezometers at the base of the dam. These piezometers will further monitor seepage and will be used to confirm the seepage measurements DWR already collects. Seepage is normal and expected, especially in large, earthen dams like Oroville. Seepage is measured and collected through a drainage system. If seepage were to dramatically change, it would indicate an issue that would need further investigation.

This work is part of early implementation of the Oroville Dam Safety Comprehensive Needs Assessment (CNA), which is focused on identifying priorities and appropriate solutions to bolster the integrity and resiliency of the Oroville Dam complex to ensure public safety. Work will begin on March 2, 2020 and will continue for several weeks, generally between the hours of 7 a.m. and 7 p.m.

There were 56 piezometers originally installed in the dam fifty years ago which, as anticipated, have since stopped functioning. DWR plans to install additional piezometers throughout the facility in the coming years.

DWR Collaborates to Seek Information on Atmospheric Rivers’ Impact on California’s Reservoirs

State and federal lawmakers have invested millions of dollars in a DWR program to research atmospheric rivers, mitigation and climate forecasting to increase knowledge about these massive streams of water vapor and wind that drop up to half of California’s yearly precipitation. DWR is collaborating with U.C. San Diego, Scripps Institution of Oceanography and the Yuba-Sutter Water Agency in a Forecast-Informed Reservoir Operations (FIRO) program to incorporate weather and water forecasts into reservoir operations decision-making. Additional information about how “hurricane hunter” planes are assisting the effort was highlighted in a recent CalMatters article.

California Natural Resources Agency Hosts Third Oroville Dam Citizens Advisory Commission Public Meeting

Thank you to everyone who participated in the third Oroville Dam Citizens Advisory Commission meeting, which took place on Friday, February 21 in Oroville. A representative of the U.S. Army Corp of Engineers discussed USACE’s role in flood management, the water control manual for Oroville Dam, and the water control manual update process. A summary and transcript of the meeting will be uploaded to the Oroville Dam Citizens Advisory Commission webpage in the coming weeks.

PG&E Removes Trees Deemed Hazardous to Powerlines

Pacific Gas & Electric (PG&E) contractors will be working on DWR property near Lakeland Road to remove trees presenting a hazard to powerlines in the area. Work activities will continue near the Thermalito Diversion Pool through the end of February.

Current Lake Operations

The elevation of Oroville’s reservoir is about 805 feet and storage is 2.25 million acre-feet. Daily average inflows to the lake have ranged between 1,556 cfs (cubic feet per second) to 2,502 cfs over the past week.

Dry conditions are forecasted this weekend and into the week of March 2. Currently, in the Northern Sierra Basin, rainfall is below average, at 50 percent of normal, and snowpack is also below average, measuring 51 percent of normal for this time of year.

Releases to the Feather River are at 2,250 cfs to meet environmental requirements in the Sacramento-San Joaquin Delta.  There is about 800 cfs flowing through the City of Oroville and 1,450 cfs being released from the Thermalito Afterbay Outlet.   

All data as of midnight 2/27/20