South Coast

Urban Water Revolution: Sustainable Water Futures for California Cities

American Society of Civil Engineers (ASCE) | July 15th, 2020

California has consistently altered natural water resources to provide water for its growing population and to support the fifth largest economy in the world. However, th

California has consistently altered natural water resources to provide water for its growing population and to support the fifth largest economy in the world. However, the old ways of coping with the California’s urban water needs—overdraft of groundwater, stream depletion, and greater imports—will no longer meet the demands of the 21st century. We examine California’s water history and present several promising solutions to the challenge of urban water security: a combination of conservation and efficiency, desalination, stormwater capture, water re-use, and water banking. These options for urban water, including direct potable reuse, will help dry cities in California and elsewhere achieve more sustainable and diversified water supply portfolios. Pilot and demonstration-scale projects, along with innovations in systems management and new regulations, point the way toward more resilient water supplies for dry cities. Movement toward regional collaboration, implementation of new technologies, and new regulatory regimes are helping to realize a one-water vision. Different cities will develop their own water supply portfolio options appropriate for their geography, values, and urban form on a path toward meeting the urban water challenges of this century.

Urbanization alters atmospheric dryness through land evapotranspiration

Nature Portfolio (Springer Nature) | September 23rd, 2023

Using Watershed Science to Build Consensus and Maximize Benefits of L.A. County’s Safe Clean Water Program

Accelerate Resilience LA (ARLA) | January 31st, 2022

To meet its diverse goals, SCWP scoring criteria, processes, and guidelines were initially developed to incentivize projects that simultaneously address water, environmen

To meet its diverse goals, SCWP scoring criteria, processes, and guidelines were initially developed to incentivize projects that simultaneously address water, environmental, MS4 compliance, and social issues. However, the first two SCWP funding cycles of Stormwater Investment Plans (SIP) featured extensive committee debate and public comments concerning the balance of these goals. This public debate illuminated the need for an assessment of the extent to which SCWP guidance, criteria, structure, and processes are successfully driving meaningful progress toward the fourteen SCWP Goals.

Valuing Urban Nature – Implications for Flood Resilience

Stanford University | June 3rd, 2019

Sea-level rise and extreme weather events such as torrential rain storms are having devastating consequences in the United States and globally. Researchers, prac

Sea-level rise and extreme weather events such as torrential rain storms are having devastating consequences in the United States and globally. Researchers, practitioners, and policymakers are increasingly calling for the use of natural and nature-based approaches to protect urban areas from flooding which has increased in frequency and intensity as a result. Natural features can help stabilize shorelines and protect communities from river flooding while, providing other co- benefits for people and ecosystems. In a new study, scientists at the Natural Capital Project developed a framework for valuating urban nature and examined different factors cities must consider when making infrastructure and other investment choices. This brief is part of a series based on that research which looks at nature’s abilityto provide resilience to flooding and the various co-benefits associated with nature-based solutions.

Variable coastal hypoxia exposure and drivers across the southern California Current

Nature Portfolio (Springer Nature) | May 25th, 2021

Declining oxygen is one of the most drastic changes in the ocean, and this trend is expected to worsen under future climate change scenarios. Spatial variability in disso

Declining oxygen is one of the most drastic changes in the ocean, and this trend is expected to worsen under future climate change scenarios. Spatial variability in dissolved oxygen dynamics and hypoxia exposures can drive differences in vulnerabilities of coastal ecosystems and resources, but documentation of variability at regional scales is rare in open-coast systems. Using a regional collaborative network of dissolved oxygen and temperature sensors maintained by scientists and fishing cooperatives from California, USA, and Baja California, Mexico, we characterize spatial and temporal variability in dissolved oxygen and seawater temperature dynamics in kelp forest ecosystems across 13° of latitude in the productive California Current upwelling system. We find distinct latitudinal patterns of hypoxia exposure and evidence for upwelling and respiration as regional drivers of oxygen dynamics, as well as more localized effects. This regional and small-scale spatial variability in dissolved oxygen dynamics supports the use of adaptive management at local scales, and highlights the value of collaborative, large-scale coastal monitoring networks for informing effective adaptation strategies for coastal communities and fisheries in a changing climate.

Variable vertical land motion and its impacts on sea level rise projections

American Association for the Advancement of Science (AAAS) | January 29th, 2025

Coastal vertical land motion (VLM), including uplift and subsidence, can greatly alter relative sea level projections and flood mitigations plans. Yet, current projection

Coastal vertical land motion (VLM), including uplift and subsidence, can greatly alter relative sea level projections and flood mitigations plans. Yet, current projection frameworks, such as the IPCC Sixth Assessment Report, often underestimate VLM by relying on regional linear estimates. Using high-resolution (90-meter) satellite data from 2015 to 2023, we provide local VLM estimates for California and assess their contribution to sea level rise both now and in future. Our findings reveal that regional estimates substantially understate sea level rise in parts of San Francisco and Los Angeles, projecting more than double the expected rise by 2050. Additionally, temporally variable (nonlinear) VLM, driven by factors such as hydrocarbon and groundwater extraction, can increase uncertainties in 2050 projections by up to 0.4 meters in certain areas of Los Angeles and San Diego. This study highlights the critical need to include local VLM and its uncertainties in sea level rise assessments to improve coastal management and ensure effective adaptation efforts.

Vegetation Responses to 2012–2016 Drought in Northern and Southern California

American Geophysical Union (AGU) | March 7th, 2019

In this study, we investigated California vegetation responses to the recent prolonged 2012–2016 drought, which was potentially the driest 4‐year span in the last 1,2

In this study, we investigated California vegetation responses to the recent prolonged 2012–2016 drought, which was potentially the driest 4‐year span in the last 1,200 years. The overall vegetation of the state has been presumed to be severely affected. However, Normalized Difference Vegetation Index (NDVI) satellite data related to vegetation greenness show that the large‐scale drought impacts on observable vegetation health were principally focused in Southern California regions, where the vegetation communities experienced striking declines in greenness. By contrast, some areas of Northern California have demonstrated significant NDVI increase and this difference in NDVI trends is evident over the past 19 years. The distinct vegetation behavior in Northern and Southern California seems to be related to a climatic dipole in the western United States, which is influenced by the large‐scale ocean‐atmosphere interactions. Some climate models predict an extension of such a dipole with greater precipitation in Northern California and less in Southern California by the end of the 21st century. Increased water demand in the south could intensify statewide intersectoral and interregional water competition in the future. However, increasing drought damage to wildlands and their terrestrial ecosystems in the south will not be relieved by any type of traditional water reallocation and irrigation effort.

Ventura County | Removing Arundo donax to Improve Groundwater Supply and Enhance Habitat

Nature Conservancy | January 1st, 2019

Removal of high water consuming exotic plants from streams and other areas may reduce water consumption thus increasing groundwater recharge. For example, Arund

Removal of high water consuming exotic plants from streams and other areas may reduce water consumption thus increasing groundwater recharge. For example, Arundo donax (commonly known as “giant reed”), uses six times more water than native plants. In Ventura County, stakeholders are working to include Arundo removal in their groundwater sustainability plan (GSP) as a supply enhancement strategy. In addition to improving groundwater supply, removing invasive plants can reduce flood risk, reduce fire risk and improve groundwater dependent ecosystems (GDEs).

Ventura County and Upper Santa Clara River Drainage Area Land and Water Use Survey, 1961

California Department of Water Resources (DWR) | April 15th, 1965

The pastoral rolling hills and  agricultural valleys of  Ventura County and the Upper Santa Clara River Drainage  Area are  experiencing rapid changes in land and 

The pastoral rolling hills and  agricultural valleys of  Ventura County and the Upper Santa Clara River Drainage  Area are  experiencing rapid changes in land and  water use. The rural character of the landscape had remained somewhat stable until the expanding perimeter of urban development of Los Angeles County spilled over into the area. Increasing industrial  decentralization in the Los Angeles area has also  brought light industry to Ventura County, and the resulting increase in employee population has afforded new opportunity for commercial service and  supply enterprises to develop. The increased momentum of industrial and residential development is paralleled by  an equivalent rise in  water utilization. As a result, additional water supplies must be developed to meet the  current and expanding needs of this area. This bulletin is one of a series presenting the results of land and water use studies made by the Department of Water Resources. It contains the results of a land and water use survey conducted in 1961 in Ventura County and the Upper Santa Clara River  Drainage Area in Los Angeles County. This report presents information on  urban and agricultural development in the study area, and the present and projected water requirements for this  cultural development.  

Ventura County: Environmental Stakeholder Representation in Groundwater Sustainability Agencies

Nature Conservancy | January 1st, 2016

The Sustainable Groundwater Management Act (SGMA) requires the preparation of groundwater sustainability plans (GSPs) for nine groundwater basins in Ventura Cou

The Sustainable Groundwater Management Act (SGMA) requires the preparation of groundwater sustainability plans (GSPs) for nine groundwater basins in Ventura County. The groundwater sustainability agencies (GSAs) that will prepare these plans consist of government agency and stakeholder representatives. Notably, in Ventura County, each basin is including specific representation of environmental interests in the GSP development process. The Fox Canyon Groundwater Management Agency (Fox Canyon) has included an environmental representative on its advisory committee and the other GSAs have included an environmental representative on their governing boards. The purpose of this organizational structure is to ensure that the groundwater needs of environmental uses are represented in the planning process.