Sacramento River

Groundwater Sustainability Plan Red Bluff Subbasin

Tehama County Flood Control and Water Conservation District | January 31st, 2022

Groundwater-dependent ecosystem map exposes global dryland protection needs

Nature Portfolio (Springer Nature) | July 17th, 2024

Guidelines for Determining Flood Flow Frequency Bulletin 17C

U.S. Geological Survey (USGS) | May 1st, 2019

Guidelines for the Small Community Drought Relief Program

California Department of Water Resources (DWR) | September 20th, 2022

Habitat Restoration in the Sacramento-San Joaquin Delta and Suisun Marsh: A Review of Science Programs

Delta Stewardship Council (Delta Council) | April 25th, 2013

Current plans call for the restoration of tens of thousands of acres of mainly intertidal habitat in the Sacramento-San Joaquin Delta and Suisun Marsh. Restoration on thi

Current plans call for the restoration of tens of thousands of acres of mainly intertidal habitat in the Sacramento-San Joaquin Delta and Suisun Marsh. Restoration on this scale presents both formidable challenges and tremendous opportunities. As part of its legislatively mandated oversight of Delta science programs, the Delta Independent Science Board reviewed these habitat restoration efforts. We held discussions with individuals from state and federal agencies, NGOs, consulting firms, and universities. We were impressed by their dedication, enthusiasm, and knowledge, as well as by the scientific and institutional challenges they face. Our findings and observations about the restoration efforts are grouped under a series of criteria for a successful restoration program. In such a program: the goals are clearly articulated; the design incorporates spatial and temporal context, adaptive management and flexibility, and monitoring; modeling is used in design and evaluation; planning and implementation are coordinated among projects; the necessary scientific expertise is available; and stakeholders are involved early and often. Our findings and recommendations agree with those reached independently by National Research Council (NRC) panels. For convenience, as in the Delta Plan, we use "the Delta" to encompass both the statutory Delta and Suisun Marsh.

Harnessing California's Waters: The Completion of the First Stage of the Pit River Power Project

Scientific American | April 1st, 1923

California is now the greatest hydro-electric power State in the Union. Over one-fifth of all the electric power generated by American water is produced in Californi

California is now the greatest hydro-electric power State in the Union. Over one-fifth of all the electric power generated by American water is produced in California. Last year, according to figures announced by Engineer H. D. McGlashan of the water resources branch of the United States Geological Survey, 3,227,262,000 kilowatt-hours were produced by water power in California. New York, which comes next with 14.72 per cent of the total. made 2,203,564,000 kilowatthours. On Saturday, September 30, 1922, an important step in California's electrification was carried out. On this date the constantly flowing waters of the Fall River were diverted through a tunnel and dropped 454 feet through steel penstocks to the Pit River Power Plant No. 1 .

HEC-HMS Models for the Sacramento and San Joaquin River Basins Comprehensive Study

U.S. Army Corps of Engineers (USACE) | August 1st, 2001

Due to several large and damaging flood events on the Sacramento and San Joaquin Rivers (California) during the 1980s and 1990s, the U.S. House of Representatives

Due to several large and damaging flood events on the Sacramento and San Joaquin Rivers (California) during the 1980s and 1990s, the U.S. House of Representatives directed the Sacramento District to develop comprehensive plans for flood control for the two rivers and to develop hydrologic and hydraulic models of the river systems. The models will be used to provide better forecasts and evaluations of flood damage reduction alternatives. Additionally, the model results will be used as input for reservoir simulation models. The Sacramento River Basin and the San Joaquin River/Tulare Lake Bed Basins comprise nearly 60,000 square miles, drain California’s Central Valley floor and receive much of their runoff from the Sierra Nevada mountain range. Developing hydrologic models for the tributary basins (which included extremely variable terrain) within a ten month time period was a formidable task. The District contacted the Hydrologic Engineering Center (HEC) to assist with the development of these models. HEC used the Hydrologic Modeling System program, HEC-HMS, and introduced the HEC-GeoHMS grid-based technology to perform the hydrologic study. GeoHMS is an ArcView® extension that provides automated subbasin delineation methods and calculates many physical characteristics used for estimation of hydrologic parameters. HEC developed and calibrated 33 individual HEC-HMS models for the major tributaries and portions of the valley floors of the Sacramento River Basin and the San Joaquin River / Tulare Lake Bed Basins. GeoHMS was used to delineate the individual river basins, perform initial subbasin delineation and develop the physical characteristics for the subbasins. Tools within GeoHMS allowed the modelers to iteratively redelineate their subbasins, as appropriate, to meet project needs. Keeping the modeling effort consistent was critical to the success of the study. To ensure this consistency of procedures and results, HEC developed modeling guidelines that each of the 11 modeling teams followed. Once the grid-based HEC-HMS models were developed, HEC contracted with the Corps’ Cold Regions Research and Engineering Laboratory (CRREL) to perform a snowmelt study for the watersheds. HEC provided a gridded precipitation file (4 km2) to CRREL. Through the use of their Distributed Snow Process Model (DSPM), CRREL then provided a gridded snowmelt/ precipitation file to HEC. DSPM computes snowmelt and rainfall depths at the soil surface on a grid-cell basis. This data is used directly by HEC-HMS as precipitation on the watershed. The ModClark rainfall to runoff transformation was used to compute the subbasin hydrographs. HEC-HMS parameter optimization models were developed at hourly flow gages for the unregulated headwater streams. The runoff parameter optimization models allowed the modelers to develop the runoff parameters necessary for the regression analysis. A number of physical characteristics were evaluated for correlation with variations in Clark’s time of concentration, TC, for the optimization models. The results of the regression analysis allowed the modelers to populate the ungaged subbasins with appropriate unit hydrograph parameters. Approximately 200 hourly flow gages and 83 reservoirs were considered in calibrating the models. The 33 individual basin models were then given to the Sacramento District.

Heresy in ENSO teleconnections: Atmospheric rivers as disruptors of canonical seasonal precipitation anomalies in the Southwestern US

Springer Nature | February 7th, 2025

In spite of forecasts for anomalous dryness based on the canonical La Niña signal, Water Years 2011, 2017, and 2023 brought copious precipitation to California and the S

In spite of forecasts for anomalous dryness based on the canonical La Niña signal, Water Years 2011, 2017, and 2023 brought copious precipitation to California and the Southwestern United States (SWUS). Although El Niño–Southern Oscillation (ENSO) is the main source of seasonal precipitation predictability for the region, outstanding Atmospheric River (AR) activity produced the unexpected regional wetness in each of these heretical water years (WYs). We define heretical WYs as those that result in precipitation anomalies that oppose those expected based on ENSO canon. We assess the contribution of ARs and other storms to these WYs, finding that heretical La Niña/El Niño WYs were characterized by anomalously robust/deficient AR activity. In California, precipitation accumulation during the heretical La Niña WYs was comparable to or even exceeded that observed during the exceedingly wet WY1998—the textbook canonical El Niño year. Our findings indicate a weaker/stronger relationship between ENSO and AR/non-AR precipitation, primarily driven by storm frequency. Although ARs can disrupt the ENSO-precipitation signal, ENSO still influences the frequency of AR precipitation in the southwestern U.S. desert, the region influenced by ARs that make landfall in Baja California, Mexico. These results highlight the complexity of ENSO's impact on precipitation in the Western US and underscore the need for a nuanced understanding of ENSO’s influence on ARs to improve seasonal precipitation prediction.

High Resolution Measurement of Levee Subsidence Related to Energy Infrastructure in the Sacramento-San Joaquin Delta

California Energy Commission (CEC) | August 31st, 2018

We assess flood overtopping potential (when flood water elevation exceeds levee elevation) to the levees surrounding the islands in the interior of California's S

We assess flood overtopping potential (when flood water elevation exceeds levee elevation) to the levees surrounding the islands in the interior of California's Sacramento-San Joaquin Delta. Because critical natural gas infrastructure is susceptible to overtopping-related disruption, we focus our analysis on regions that are crossed by the network of the state's natural gas pipelines. We use laser scanning data collected during 2015-2016 to estimate subsidence rates since 2007 when an earlier, Delta-wide, airborne laser-scanning topographic dataset was collected. For each levee studied, we combine: (1) the estimated subsidence rate, (2) a conservative range of sea-level rise projections and, (3) an estimate of the 100-year freshwater flood stage to project the time until exceedance of the federal levee height standard (PL84-99). We find that subsidence rates vary from 0-5 centimeters per year (cm/yr) with mean values of ~1-2 cm/year. Local gradients in subsidence can be on the order of cms/yr over a distance of 10s of meters parallel to the levee crests, and these types of gradients are present near some pipeline crossings. The Sherman Island region has subsidence rates close to a factor of 2 greater than other areas considered. Our projections indicate general ranges of exceedance date from about 2060 (fast sea-level rise scenario) to 2080 (slow sea-level rise scenario) with some places projected to exceed threshold by about 2050.

Highlights Central Valley Flood Protection Plan 2022 Update

California Department of Water Resources (DWR) | January 23rd, 2023

The 2022 Central Valley Flood Protection Plan Update was adopted by the Central Valley Flood Protection Board on December 16th, 2022. Just days later, beginning on Decemb

The 2022 Central Valley Flood Protection Plan Update was adopted by the Central Valley Flood Protection Board on December 16th, 2022. Just days later, beginning on December 27th, 2022, a series of atmospheric rivers began to impact California. This succession of atmospheric rivers resulted in 34 trillion gallons of water falling across California in 24 days, and 21 forecast points in the Central Valley reaching flood or monitor stage. Governor Gavin Newsom declared a state of emergency on January 4th, 2023; federal emergency and disaster declarations followed soon thereafter. These events underscore the importance of the CVFPP as the State’s strategic blueprint for investment in flood risk reduction in the Central Valley, especially in an era of whiplash weather—from drought to flooding— driven by the impacts of climate change.