South Coast

Piloting a Water Rights Information System for California

Center for Law, Energy, and the Environment (CLEE) | July 15th, 2021

California’s complex water management challenges are growing and intensifying. Systemic stressors like the more frequent and severe droughts and floods driven by climat

California’s complex water management challenges are growing and intensifying. Systemic stressors like the more frequent and severe droughts and floods driven by climate change are only making it harder to respond. Accordingly, California needs to dramatically improve the ability of local, regional, and State entities to make agile and effective water management decisions. We believe doing so will require enhanced understanding of our water resources and how they align with the needs of a range of agencies and stakeholders. Water rights data provide a crucial opportunity for advancing this understanding. We find that modernizing water rights data is feasible, affordable, and can increase transparency and clarity for better decision-making.

Piru Basin Groundwater Sustainability Plan

Fillmore and Piru Basins Groundwater Sustainability Agency | December 16th, 2021

The Piru Basin (the Basin) is managed (along with the downslope Fillmore Basin) by the Fillmore and Piru Basins Groundwater Sustainability Agency (Agency). The Basin is p

The Piru Basin (the Basin) is managed (along with the downslope Fillmore Basin) by the Fillmore and Piru Basins Groundwater Sustainability Agency (Agency). The Basin is planned to remain sustainable over the Sustainable Groundwater Management Act (SGMA) implementation and sustainability period, based on the current understanding of historical, current (2019), and projected (2022 through 2072) groundwater conditions in relation to the sustainability indicators specified in SGMA. A sustainability indicator refers to any of the effects caused by groundwater conditions occurring throughout the basin that, when significant and unreasonable, cause undesirable results. The Agency, with consideration of feedback from active stakeholder engagement, has identified and planned for the prevention of significant and unreasonable undesirable results.

Plan writing as a policy tool: instrumental, conceptual, and tactical uses of water management plans in California

Journal of Environmental Studies and Sciences (Springer) | February 24th, 2022

Numerous environmental regulations require organizations to codify prospective activities in a written plan. However, evidence suggests that many plans are never implemen

Numerous environmental regulations require organizations to codify prospective activities in a written plan. However, evidence suggests that many plans are never implemented, raising questions about why public agencies continually require plans, whether mandating plans allows agencies to meet their policy aims, and what additional purposes plans serve. Adopting concepts from literature on research utilization, we develop a plan use typology, defining instrumental use as occurring when the requirement to write a plan directly addresses a stated policy problem, conceptual use as occurring when the requirement to write a plan indirectly addresses a policy problem by raising awareness of an issue or improving governance capacity, and tactical use as occurring when the requirement to write a plan serves a political or symbolic purpose unrelated to solving the policy problem. We then apply the typology to four California statutes that require local and regional utilities to write water management plans. We first assess the statutes to identify the goals underlying the requirement to write a plan and assess what plan uses are emphasized in guidance documents and the written plans themselves. Lastly, we interview the plan writing organizations to capture their perspectives on the value and limitations of these plans. We find that legislators turn to plans to support instrumental and conceptual goals but that the plans themselves and the way they are used by authoring agencies primarily serve conceptual and tactical uses, suggesting a disconnect between the policy goals underlying plans and their actual use.

Planned operation of large-scale water-distribution system

American Society of Civil Engineers (ASCE) | May 1st, 1995

A water-supply-distribution-system planning model has been developed using a directed graph algorithm as its pre- and post-processors and a linear programming (LP) proced

A water-supply-distribution-system planning model has been developed using a directed graph algorithm as its pre- and post-processors and a linear programming (LP) procedure as an “intelligent” system operator at its core. The directed graph, as a preprocessor, is used to produce a mathematical representation of the distribution system in question, to check the consistency and correctness of the network topology before an input file is created for the LP procedure. In the postprocessing mode, the directed graph generates files for graphical displays of model results and performs graph analyses such as depth- and breadth-first traversals, cut-set and connectivity for evaluating water-quality blending, tracking of source-to-demand contributions, system reliability, and lifeline objectives. Unlike the conventional formulation of a resource-allocation problem, the demand requirements, storage capacities, and other system constraints are removed from the constraint set and translated into a composite objective function. This methodology was successfully applied to the Metropolitan Water District of Southern California's (MWD's) distribution system. The results indicate that the combination of using an LP procedure and graph algorithm is a very versatile tool for solving large-scale water-distribution problems. This paper documents the concept used in developing the system-planning model and the results of its application to a simplified example as well as application to four case studies involving the entire MWD's distribution system.

Points of Interest Los Angeles Aqueduct System

Los Angeles Department of Water & Power (LADWP) | September 3rd, 1979

Poleward shift of the major ocean gyres detected in a warming climate

American Geophysical Union (AGU) | February 24th, 2020

Recent evidence shows that wind‐driven ocean currents, like the western boundary currents, are strongly affected by global warming. However, due to insufficient observa

Recent evidence shows that wind‐driven ocean currents, like the western boundary currents, are strongly affected by global warming. However, due to insufficient observations both on temporal and spatial scales, the impact of climate change on large‐scale ocean gyres is still not clear. Here, based on satellite observations of sea surface height and sea surface temperature, we find a consistent poleward shift of the major ocean gyres. Due to strong natural variability, most of the observed ocean gyre shifts are not statistically significant, implying that natural variations may contribute to the observed trends. However, climate model simulations forced with increasing greenhouse gases suggest that the observed shift is most likely to be a response of global warming. The displacement of ocean gyres, which is coupled with the poleward shift of extratropical atmospheric circulation, has broad impacts on ocean heat transport, regional sea level rise and coastal ocean circulation.

Population exposure to pre-emptive de-energization aimed at averting wildfires in Northern California

Environmental Research Letters (IOP) | August 26th, 2020

Recent extreme fire seasons in California have prompted utilities such as Pacific Gas and Electric to pre-emptively de-energize portions of the electrical grid during per

Recent extreme fire seasons in California have prompted utilities such as Pacific Gas and Electric to pre-emptively de-energize portions of the electrical grid during periods of extreme fire weather to reduce the risk of powerline-related fire ignitions. The policy was deployed in 2019, resulting in 12 million person-days of power outages and widespread societal disruption. Retrospective weather and vegetation moisture data highlight hotspots of historical risk across northern California. We estimate an average of 1.6 million person-days of de-energization per year, based on recent historical climate conditions and assuming publicly stated utility de-energization thresholds. We further estimate an additional 70% increase in the population affected by de-energization when vegetation remains abnormally dry later into autumn—suggesting that climate change will likely increase population vulnerable to de-energization. Adaptation efforts to curtail fire risk can be beneficial, but efforts to prepare affected populations, modernize the grid, and refine decision-making surrounding such policies have high potential to reduce the magnitude of negative externalities experienced during the 2019 de-energization events.

Postfire Sediment Mobilization and its Downstream Implications Across California, 1984–2021

American Geophysical Union (AGU) | August 27th, 2024

Potential impacts of increased coastal flooding in California due to sea-level rise

Climatic Change (Springer) | November 24th, 2011

California is likely to experience increased coastal flooding and erosion caused by sea-level rise over the next century, affecting the state’s population, infrastructu

California is likely to experience increased coastal flooding and erosion caused by sea-level rise over the next century, affecting the state’s population, infrastructure, and environment. As part of a set of studies on climate change impacts to California, this paper analyzes the potential impacts from projected sea-level rise if no actions are taken to protect the coast (a “no-adaptation scenario”), focusing on impacts to the state’s population and infrastructure. Heberger et al. (2009) also covered effects on wetlands, costs of coastal defenses, and social and environmental justice related to sea-level rise. We analyzed the effect of a medium-high greenhouse gas emissions scenario (Special Report on Emissions Scenarios A2 in IPCC 2000) and included updated projections of sea-level rise based on work by Rahmstorf (Science 315(5810): 368, 2007). Under this scenario, sea levels rise by 1.4 m by the year 2100, far exceeding historical observed water level increases. By the end of this century, coastal flooding would, under this scenario, threaten regions that currently are home to approximately 480,000 people and $100 billion worth of property. Among those especially vulnerable are large numbers of low-income people and communities of color. A wide range of critical infrastructure, such as roads, hospitals, schools, emergency facilities, wastewater treatment plants, and power plants will also be at risk. Sea-level rise will inevitably change the character of California’s coast; practices and policies should be put in place to mitigate the potentially costly and life-threatening impacts of sea-level rise.

PPIC Statewide Survey: Californians and the Environment

Public Policy Institute of California (PPIC) | July 28th, 2022

With California facing a severe drought and wildfire season, public awareness has risen of the impact of climate change as well as state policies to reduce greenhouse gas

With California facing a severe drought and wildfire season, public awareness has risen of the impact of climate change as well as state policies to reduce greenhouse gas emissions. A sharp increase in petroleum prices has led to discussions about expanding oil production and renewable energy sources. These are among the key findings of a statewide survey on environmental issues conducted by the Public Policy Institute of California from July 8 to 15, 2022.