Managing Lake Oroville in an Above-Average Water Year

[WB Staff]

For anyone who enjoys the abundant recreation opportunities at Lake Oroville, a full reservoir is a welcome site after years of drought and lower-than-normal lake levels due to spillway reconstruction. But with above average precipitation and snowpack in the Sierras above the Feather River watershed, the California Department of Water Resources (DWR) is also managing reservoir levels to accommodate for spring inflow.

It’s common for Lake Oroville to stay relatively full during the summer months after an above average water year like the one we’re experiencing in 2018-2019. In 2010-2011, another very wet year, the reservoir was filled to near-capacity or capacity – an elevation between 898 and 900 feet – for the entire month of July. This provided optimal recreation opportunities and refilled California’s vital water bank account to help the entire state get through the tail-end of a prolonged drought.

DWR operates the Oroville reservoir to provide flood protection, water supply, flows for ecosystems and water quality, and recreation benefits. Reservoir levels are managed according to the standard U.S. Army Corps Water Manual and through collaboration with the National Weather Service, the U.S. Army Corps of Engineers, and in coordination with other local, private, and federal reservoir operators including Yuba Water Agency and the U.S. Bureau of Reclamation. DWR makes real-time operational adjustments based on a number of factors and data including snowpack analysis, expected run off, releases from upstream facilities, weather forecasts, and downstream flow and water quality requirements.