Submittal of 2015 Agricultural Water Management Plans and Implementation of Efficient Water Management Practices Report

California Department of Water Resources (DWR) | September 22nd, 2017

Senate Bill X7-7, the Water Conservation Act of 2009 (SB X7-7), requires agricultural water suppliers who provide water to more than 25,000 irrigated acres (excluding acr

Senate Bill X7-7, the Water Conservation Act of 2009 (SB X7-7), requires agricultural water suppliers who provide water to more than 25,000 irrigated acres (excluding acreage irrigated by recycled water) to adopt and submit Agricultural Water Management Plans (AWMPs or Plans) to the Department of Water Resources (DWR) and to implement Efficient Water Management Practices (EWMPs), including two critical EWMPs: the measurement and volumetric pricing of water deliveries. These AWMPs were due by January 31, 2016. Governor Brown’s Executive Order B-29-15 required agricultural water suppliers that provide water from 10,000 to 25,000 irrigated acres to submit AWMPs by July 1, 2016. California Water Code (CWC) §10845(a) and (b) directs DWR to report on the following: • The status of adopted AWMPs • Exemplary elements of adopted plans • An evaluation of the effectiveness of implemented AWMPs in promoting efficient agricultural water management practices • Recommendations relating to proposed changes to the AWMP reporting requirements and EWMPs Additionally, CWC section 10608.48(g) directs DWR in consultation with the State Water Resources Control Board (SWRCB) to prepare and submit to the Legislature a report on: • EWMPs that have been implemented or are planned to be implemented, and • An assessment of the manner in which the implementation of an EWMP has affected and will affect agricultural operations and an estimation of water use efficiency improvements, if any. This legislative report addresses the above requirements in a single report and documents the status of AWMP submittals and the implementation of associated EWMPs or best management practices (BMPs) for those water suppliers submitting a United States Bureau of Reclamation (Reclamation) plan in lieu of a plan meeting SB X7-7 criteria.1 A table comparing the SB X7-7 EWMPs and Reclamation BMPs is in Appendix B. Further information on SB X7-7 requirements and legislative reports are available at http://www.water.ca.gov/wateruseefficiency/sb7/.

Submittal of Report – Status Report on Implementation of the California Statewide Groundwater Elevation Monitoring Program Years 2012-2015

California Department of Water Resources (DWR) | April 1st, 2016

Senate Bill X7 6 (SBX7 6) (Chapter 1, Statutes of 2009) added provisions for groundwater monitoring to Division 6 of the Water Code (Water Code § 10920 et seq.). The bil

Senate Bill X7 6 (SBX7 6) (Chapter 1, Statutes of 2009) added provisions for groundwater monitoring to Division 6 of the Water Code (Water Code § 10920 et seq.). The bill authorized the Department of Water Resources (DWR) to establish permanent, locally managed, groundwater elevation monitoring and reporting for all 515 groundwater basins identified in DWR Bulletin 118, California’s Groundwater, as shown in Figure 1. Groundwater elevation data are foundational to improving the management and sustainability of California's groundwater resources. DWR developed the California Statewide Groundwater Elevation Monitoring (CASGEM) Program to implement SBX7 6. Water Code section 12924(c) requires DWR to report the status of the CASGEM Program to the Governor and Legislature by January 1, 2012, and thereafter in years ending in “5” or “0”. This report covers calendar years 2012 through 2015. The overall purpose of the CASGEM Program is to track seasonal and long-term groundwater elevation trends in groundwater basins statewide. The Water Code directs DWR to rely on, and build upon, the many established local agency groundwater monitoring and management efforts throughout the state. DWR works cooperatively with local agencies, referred to as CASGEM “Monitoring Entities,” to collect and maintain groundwater elevation data in a manner that is readily and widely available to the public. During 2010 and 2011, the first two years of the CASGEM Program, DWR focused its efforts on initiating the CASGEM Program and ensuring that Monitoring Entities would, by January 2012, be able to submit groundwater elevation data electronically.

Subsidence (2004-2009) in and near lakebeds of the Mojave River and Morongo groundwater basins, southwest Mojave Desert, California

U.S. Geological Survey (USGS) | July 1st, 2014

Subsidence: A critical challenge to Friant-Kern canal water deliveries

Friant Water Authority | January 17th, 2018

The Friant Water Authority is facing a critical challenge right now - one that has reduced our ability to deliver water to many Friant Division Contractor’s

The Friant Water Authority is facing a critical challenge right now - one that has reduced our ability to deliver water to many Friant Division Contractor’s by nearly 60%. It is a challenge that must be met today if we are to ensure our long-term commitment to delivering high-quality, dependable water, in the amounts needed by farmers and cities in the San Joaquin Valley.

Subsidized or subsidizing? Municipal drinking water service funds in California

Utilities Policy (Elsevier) | September 29th, 2022

In the longstanding debate over efficiency and effectiveness in drinking water provision between public versus privately governed systems, one of the main contention poin

In the longstanding debate over efficiency and effectiveness in drinking water provision between public versus privately governed systems, one of the main contention points is the reasons for different bill levels imposed by city-run as compared to privately owned water systems. In this study, we examine one potential explanation for disparities in bills: whether cities use their general funds to subsidize their drinking water fund operations or vice versa. Either practice goes against “user pays” principles, as pointed out by critics of municipal operation. However, the claims have not been tested empirically at scale. We extract and analyze city water enterprise fund financial data from the California State Controller Cities Raw Data of Financial Transaction Reports to empirically assess the extent to which and reasons why interfund transfers occur in California's 267 municipally owned water utilities. We find very little evidence that substantial interfund transfers, in either direction, occur between water enterprise funds and general funds within California cities, indicating that enterprise fund control measures are generally successful. These findings suggest that with proper regulation, the municipal fund subsidy debate is essentially a distraction from the real reasons why municipal and other water provider rates differ substantially.

Subsurface Geometry of the San Andreas Fault in Southern California: Results from the Salton Seismic Imaging Project (SSIP) and Strong Ground Motion Expectations

Seismological Society of America (SSA) | August 1st, 2017

The San Andreas fault (SAF) is one of the most studied strike‐slip faults in the world; yet its subsurface geometry is still uncertain in most locations. The Salton S

The San Andreas fault (SAF) is one of the most studied strike‐slip faults in the world; yet its subsurface geometry is still uncertain in most locations. The Salton Seismic Imaging Project (SSIP) was undertaken to image the structure surrounding the SAF and also its subsurface geometry. We present SSIP studies at two locations in the Coachella Valley of the northern Salton trough. On our line 4, a fault‐crossing profile just north of the Salton Sea, sedimentary basin depth reaches 4 km southwest of the SAF. On our line 6, a fault‐crossing profile at the north end of the Coachella Valley, sedimentary basin depth is ∼2–3km∼2–3  km and centered on the central, most active trace of the SAF. Subsurface geometry of the SAF and nearby faults along these two lines is determined using a new method of seismic‐reflection imaging, combined with potential‐field studies and earthquakes. Below a 6–9 km depth range, the SAF dips ∼50°–60°∼50°–60° NE, and above this depth range it dips more steeply. Nearby faults are also imaged in the upper 10 km, many of which dip steeply and project to mapped surface fault traces. These secondary faults may join the SAF at depths below about 10 km to form a flower‐like structure. In Appendix D, we show that rupture on a northeast‐dipping SAF, using a single plane that approximates the two dips seen in our study, produces shaking that differs from shaking calculated for the Great California ShakeOut, for which the southern SAF was modeled as vertical in most places: shorter‐period (⁠T<1sT<1  s⁠) shaking is increased locally by up to a factor of 2 on the hanging wall and is decreased locally by up to a factor of 2 on the footwall, compared to shaking calculated for a vertical fault.

Subsurface water flux in California's Central Valley and its source watershed from space geodesy

American Geophysical Union (AGU) | September 29th, 2022

We combine measurements from Global Positioning System positioning and Gravity Recovery and Climate Experiment gravity to infer change in water components in Central Vall

We combine measurements from Global Positioning System positioning and Gravity Recovery and Climate Experiment gravity to infer change in water components in Central Valley and its source watershed, the Sacramento-San Joaquin-Tulare River basin better than possible with either technique separately. We find that the Central Valley has lost groundwater from 2006 to 2021 at 2.2 ± 0.7 km 3/ yr (95% confidence limits follow the “±” sign), with 2/3 of the groundwater loss occurring in the southern part of the Valley. We estimate the seasonal recharge and loss of subsurface water in the Central Valley. Comparison to a model accounting for precipitation, evapotranspiration, and river water entering and leaving the Central Valley suggests that deep groundwater may be flowing from the Sierra Nevada mountains into the Central Valley.

Suisun Marsh Monitoring Program Annual Data Summary Water Year 1999

California Department of Water Resources (DWR) | July 31st, 2001

This report summarizes data collected in the Suisun Marsh during Water Year 1999 (October 1, 1998 through September 30, 1999) pursuant to the following agreements, perm

This report summarizes data collected in the Suisun Marsh during Water Year 1999 (October 1, 1998 through September 30, 1999) pursuant to the following agreements, permits, and water rights decisions: • State Water Resources Control Board Decision 1485, August 1978 (SWRCB 1978); • State Water Resources Control Board Order WR 95-6, 1995 (SWRCB 1995a); • Suisun Marsh Preservation Agreement, 1987 (USBR and others 1987); • Suisun Marsh Monitoring Agreement, 1987 (DWR and others 1987); • San Francisco Bay Conservation and Development Commission Permit No. 35-78 (M) Amendment 7, 1997 (for construction of the initial facilities, namely the Roaring River Distribution System, Morrow Island Distribution System, and Goodyear Slough Outfall) (BCDC 1997); • San Francisco Bay Conservation and Development Commission Permit No. 4-84 (M) Amendment 4, 1991 (for construction of the Suisun Marsh Salinity Control Gates) (1991); and, • U.S. Army Corps of Engineers Permit No. 16223E58 (for construction of the Suisun Marsh Salinity Control Gates), Special Condition 1, 1986 (USACE 1986). This report fulfills a portion of the annual reporting requirements of the above-listed, agreements, permits, and water rights decisions as detailed in Table 1. Remaining reporting requirements will be fulfilled in other Department of Water Resources (DWR) and/or University of California Davis reports. DWR and the California Department of Fish and Game (DFG) primarily collected data summarized in this report. The data include • general hydrologic data; • continuous channel water specific conductance and tidal height measurements; • marsh-wide vegetation survey update; • waterfowl abundance; and • salt marsh harvest mouse occurrence.

Summarizing Relationships among Landfalling Atmospheric Rivers, Integrated Water Vapor Transport, and California Watershed Precipitation 1982–2019

American Meteorological Society (AMS) | September 16th, 2022

Atmospheric rivers (ARs) are defined as corridors of enhanced integrated water vapor transport (IVT) and produce large fractions of annual precipitation in regions with c

Atmospheric rivers (ARs) are defined as corridors of enhanced integrated water vapor transport (IVT) and produce large fractions of annual precipitation in regions with complex terrain along the western coastlines of midlatitude continents (e.g., 30%–50% along the U.S. West Coast in California). This study investigates this relationship among landfalling ARs, IVT, and watershed mean areal precipitation (MAP) for a 38-yr period over California. On average, the daily average IVT magnitude at different coastal locations explains ∼34% of the variance in annual watershed MAP across 140 Hydrologic Unit Code 8 (HUC-8) watersheds with large spatial variability across California. Further investigation of the IVT magnitude and direction at coastal locations illustrated that accounting for water vapor transport direction increases the explained variance in annual MAP to an average of 45%, with highest values (∼65%) occurring in watersheds over Northern and coastal California. Similar investigation of the lower-tropospheric water vapor flux vector at 850 and 925 hPa revealed further increases in the explained variance in annual MAP to an average of >50%. The results of this study 1) emphasize the importance of both IVT direction and water vapor flux altitude to watershed MAP, 2) align well with previous studies for select locations that highlight the importance of upslope (i.e., lower tropospheric) water vapor flux during landfalling ARs and precipitation, and 3) motivate the development of AR-related and watershed-centric forecast tools that incorporate IVT direction and water vapor flux altitude parameters in addition to IVT magnitude.

Summary & Evaluation of California Coastal Chinook Salmon and Northern California Steelhead 2016

National Marine Fisheries Service (NMFS) | April 11th, 2016

Many West Coast salmon and steelhead (Oncorhynchus sp.) stocks have declined substantially from their historic numbers and now are at a fraction of their historical abund

Many West Coast salmon and steelhead (Oncorhynchus sp.) stocks have declined substantially from their historic numbers and now are at a fraction of their historical abundance. There are several factors that contribute to these declines, including: overfishing, loss of freshwater and estuarine habitat, hydropower development, poor ocean conditions, and hatchery practices.  These factors, among others, led to the National Marine Fisheries Service‘s (NMFS) listing of 28 salmon and steelhead stocks in California, Idaho, Oregon, and Washington under the Federal Endangered Species Act (ESA). The ESA, under section 4(c)(2), directs the Secretary of Commerce to review the listing classification of threatened and endangered species at least once every five years. After completing this review, the Secretary must determine if any species should be: (1) removed from the list; (2) have its status changed from threatened to endangered; or (3) have its status changed from endangered to threatened. NMFS completed a 5-year status review in 2011 and concluded the status for threatened California Coastal (CC) Chinook salmon and Northern California (NC) steelhead should remain as threatened (NMFS 2011a, NMFS 2011b). This document summarizes NMFS’s current 5-year review for the threatened CC Chinook salmon and NC steelhead.