North Lahontan

Statement of Findings regarding the Approval of the Tahoe Valley - Tahoe South Subbasin Alternative Groundwater Sustainability Plan

California Department of Water Resources (DWR) | July 17th, 2019

Statement of Findings regarding the Periodic Review and Approval of the Tahoe Valley - Tahoe South Subbasin Alternative Groundwater Sustainability Plan

California Department of Water Resources (DWR) | June 27th, 2024

Status of 2020 Agricultural Water Management Plans and Implementation of Efficient Water Management Practices Report

California Department of Water Resources (DWR) | January 25th, 2024

As required by the California Water Code (CWC), Agricultural Water Suppliers (AWS) must implement Efficient Water Management Practices (EWMPs) and submit an Agricultural

As required by the California Water Code (CWC), Agricultural Water Suppliers (AWS) must implement Efficient Water Management Practices (EWMPs) and submit an Agricultural Water Management Plan (AWMP) to the Department of Water Resources (DWR) every five years. Agricultural Water Suppliers subject to United States Bureau of Reclamation (Reclamation) requirements for a Water Conservation Plan (Reclamation Plan) may submit those plans to DWR in lieu of an AWMP. DWR then reports to the Legislature on the status of AWMPs, including outstanding elements, and implementation of EWMPs or Reclamation Best Management Practices (EWMPs/BMPs). This legislative report addresses the requirements for reporting on AWMPs and EWMPs in a single report that documents the status of AWMP submittals and the implementation of associated EWMPs. This report is the final Legislative report on EWMPs under CWC Section 10608.48(g).

Status of 2020 Urban Water Management Plans

California Department of Water Resources (DWR) | July 25th, 2023

As required by the California Water Code (CWC), every five years Urban Water Suppliers must submit an Urban Water Management Plan (UWMP) to the Department of Water Resour

As required by the California Water Code (CWC), every five years Urban Water Suppliers must submit an Urban Water Management Plan (UWMP) to the Department of Water Resources (DWR). DWR then reports to the Legislature on the status of UWMPs and Water Shortage Contingency Plans (WSCPs) and exemplary elements. Key Findings: * 95% (417 of 438) of Urban Water Suppliers submitted plans. * 97% (374 of 386) of Urban Retail Suppliers that submitted UWMPs met their water use reduction targets. * Statewide per capita urban water use was down 32% by 2020 from baseline period (suppliers identify a continuous 10-year or 15-year baseline period between 1995 and 2010). * 94% (393 of 417) of Urban Water Suppliers anticipate being able to manage any water shortages by implementing their Water Shortage Contingency Plans.

Storing and managing water for the environment is more efficient than mimicking natural flows

Nature Portfolio (Springer Nature) | June 27th, 2024

Strategic stream gauging network design for sustainable water management

Nature Portfolio (Springer Nature) | June 3rd, 2024

Stream gauging stations that monitor the flow of water in rivers and streams provide critical information to water managers, but biases and gaps in gauge placement, compo

Stream gauging stations that monitor the flow of water in rivers and streams provide critical information to water managers, but biases and gaps in gauge placement, compounded by gauge deactivations, limit our ability to track river flows and address global water challenges. Here we introduce an approach for identifying gauging sites to efficiently fill gaps in monitoring coverage within river networks while also addressing water management priorities, including reservoir operations, biodiversity conservation and hydroclimatic monitoring. Applying this approach to gauges in California, United States, we found substantial gaps in the stream monitoring network. Hypothetically reconfiguring gauges to locations that maximize coverage and representation of management objectives highlights the current network’s biases. Through the strategic reactivation and placement of additional gauges, we demonstrate how stream gauging networks can be designed to support sustainable water management.

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.

Sustainable Landscapes in California: A Guidebook for Commercial and Industrial Site Managers

Pacific Institute | August 20th, 2020

Sustainable landscaping offers a solution in balance with the local climate and ecology, and actively contributes to community and watershed health by providing economic,

Sustainable landscaping offers a solution in balance with the local climate and ecology, and actively contributes to community and watershed health by providing economic, social, and environmental benefits. This guidebook provides simple steps to consider, select, and install sustainable landscaping. Aimed specifically at businesses and communities in California, the guidebook includes information on turf replacement, installation of bioswales and rain gardens, permeable pavement, green roofs, and rain tanks and cisterns. Self-assessments guide the user through the selection and installation process.

Tahoe: State of the Lake Report 2025

University of California, Davis (UC Davis) | July 18th, 2025

UC Davis has conducted research at Lake Tahoe since 1950, and scientists from UC Davis Tahoe Environmental Research Center have been monitoring conditions at the lake con

UC Davis has conducted research at Lake Tahoe since 1950, and scientists from UC Davis Tahoe Environmental Research Center have been monitoring conditions at the lake continuously since 1968. This has created a unique document of change for one of the world’s most iconic and vulnerable lakes.

Taming wildfires in the context of climate change: The case of the United States

Organisation for Economic Co-operation and Development (OECD) | January 22nd, 2024

Shifts in climate cycles (e.g., Pacific Decadal Oscillation, El Niño-Southern Oscillation), combined with ongoing changes in drought, temperature and snowmelt, together,

Shifts in climate cycles (e.g., Pacific Decadal Oscillation, El Niño-Southern Oscillation), combined with ongoing changes in drought, temperature and snowmelt, together, have contributed to the overall warmer, drier conditions that fuel extreme wildfires (Environmental Protection Agency, 2022[4]; Kitzberger et al., 2007[10]; Westerling, 2016[11]). The period with the largest increase in area burned coincides with many of the warmest years on record nationwide (Environmental Protection Agency, 2022[4]). Such changes are especially visible in the western United States, where the peak extent of area burned now occurs about one month earlier than just two decades ago. Other factors including longer dry seasons and drier soils and vegetation are increasingly creating the conditions for catastrophic wildfires (Environmental Protection Agency, 2022[4]; US Global Change Research Program, 2018[9]). Wildfires are also further spreading into areas historically unaccustomed to fire, including high elevation areas in the west of the country (Figure 1.2) (OECD, 2023[2]; Alizadeh et al., 2021[12]), which may be less prepared for wildfires and potentially harmed by its impacts.