California’s Water: The Sacramento-San Joaquin Delta

Public Policy Institute of California (PPIC) | October 1st, 2016

The Delta is the deteriorating, fragile hub of California’s water supply system. Critical decisions about its future are pending. This brief looks at various approa

The Delta is the deteriorating, fragile hub of California’s water supply system. Critical decisions about its future are pending. This brief looks at various approaches being proposed to improve management and health of the Delta. This publication is part of a briefing kit that summarizes a dozen of the state’s most pressing water management issues.

Can restoring water and sediment fluxes across a mega-dam cascade alleviate a sinking river delta?

American Association for the Advancement of Science (AAAS) | May 1st, 2024

Civic Engagement and Water Data: How Can California Make Data Work for Decision Makers?

University of California, Berkeley (UC Berkeley) | September 1st, 2020

 Much attention is focused on water data in California, and for good reason. California is struggling to make decisions that adapt its water systems to pressures such as

 Much attention is focused on water data in California, and for good reason. California is struggling to make decisions that adapt its water systems to pressures such as climate change and population growth. Fully informed decisions are impossible without accurate and accessible data and information to support them. California already produces immense amounts of water-related data. However, agencies and stakeholders currently struggle to bring these data together to support routine decision making. Overall, we lack any systematic understanding of whether and how existing data can support the needs of decision makers. 

Clean Watersheds Needs Survey 2012

U.S. Environmental Protection Agency (EPA) | December 13th, 2012

Climate change risks to US infrastructure: impacts on roads, bridges, coastal development, and urban drainage

American Meteorological Society (AMS) | January 23rd, 2014

Changes in temperature, precipitation, sea level, and coastal storms will likely increase the vulnerability of infrastructure across the United States. Using four

Changes in temperature, precipitation, sea level, and coastal storms will likely increase the vulnerability of infrastructure across the United States. Using four models that analyze vulnerability, impacts, and adaptation, this paper estimates impacts to roads, bridges, coastal properties, and urban drainage infrastructure and investigates sensitivity to varying greenhouse gas emission scenarios, climate sensitivities, and global climate models. The results suggest that the impacts of climate change in this sector could be large, especially in the second half of the 21st century as sea-level rises, temperature increases, and precipitation patterns become more extreme and affect the sustainability of long-lived infrastructure. Further, when considering sea-level rise, scenarios which incorporate dynamic ice sheet melting yield impact model results in coastal areas that are roughly 70 to 80 % higher than results that do not incorporate dynamic ice sheet melting. The potential for substantial economic impacts across all infrastructure sectors modeled, however, can be reduced by cost-effective adaptation measures. Mitigation policies also show potential to reduce impacts in the infrastructure sector – a more aggressive mitigation policy reduces impacts by 25 to 35 %, and a somewhat less aggressive policy reduces impacts by 19 to 30 %. The existing suite of models suitable for estimating these damages nonetheless covers only a small portion of expected infrastructure sector effects from climate change, so much work remains to better understand impacts on electric and telecommunications networks, rail, and air transportation systems. In addition, the effects of climate-induced extreme events are likely to be important, but are incompletely understood and remain an emerging area for research.

Climate Warming and Water Management Adaptation for California

Climatic Change (Springer) | June 10th, 2010

The ability of California’s water supply system to adapt to long-term climatic and demographic changes is examined. Two climate warming and a historical climate

The ability of California’s water supply system to adapt to long-term climatic and demographic changes is examined. Two climate warming and a historical climate scenario are examined with population and land use estimates for the year 2100 using a statewide economic-engineering optimization model of water supply management. Methodologically, the results of this analysis indicate that for long-term climate change studies of complex systems, there is considerable value in including other major changes expected during a long-term time-frame (such as population changes), allowing the system to adapt to changes in conditions (a common feature of human societies), and representing the system in sufficient hydrologic and operational detail and breadth to allow significant adaptation. While the policy results of this study are preliminary, they point to a considerable engineering and economic ability of complex, diverse, and intertied systems to adapt to significant changes in climate and population. More specifically, California’s water supply system appears physically capable of adapting to significant changes in climate and population, albeit at a significant cost. Such adaptation would entail large changes in the operation of California’s large groundwater storage capacity, significant transfers of water among water users, and some adoption of new technologies.

Climate-informed hydrologic modeling and policy typology to guide managed aquifer recharge

American Association for the Advancement of Science (AAAS) | April 21st, 2021

Harvesting floodwaters to recharge depleted groundwater aquifers can simultaneously reduce flood and drought risks and enhance groundwater sustainability. However, deploy

Harvesting floodwaters to recharge depleted groundwater aquifers can simultaneously reduce flood and drought risks and enhance groundwater sustainability. However, deployment of this multibeneficial adaptation option is fundamentally constrained by how much water is available for recharge (WAFR) at present and under future climate change. Here, we develop a climate-informed and policy-relevant framework to quantify WAFR, its uncertainty, and associated policy actions. Despite robust and widespread increases in future projected WAFR in our case study of California (for 56/80% of subbasins in 2070–2099 under RCP4.5/RCP8.5), strong nonlinear interactions between diversion infrastructure and policy uncertainties constrain how much WAFR can be captured. To tap future elevated recharge potential through infrastructure expansion under deep uncertainties, we outline a novel robustness-based policy typology to identify priority areas of investment needs. Our WAFR analysis can inform effective investment decisions to adapt to future climate-fueled drought and flood risk over depleted aquifers, in California and beyond.

Collateral Damage: A citizen’s guide to fish kills and habitat degradation at the state and federal water project pumps in the Delta

Bay Institute | March 1st, 2012

Large-scale fish kills and habitat destruction aren’t an unusual occurrence at the giant federal and state pumps that export water from the Sacramento-San Joaquin Delta

Large-scale fish kills and habitat destruction aren’t an unusual occurrence at the giant federal and state pumps that export water from the Sacramento-San Joaquin Delta to agribusinesses and cities in the southern half of the state. These events are business as usual. • Every day, between 870 and 61,000 fish – including from 200 to 42,000 native and endangered fishes – are “salvaged” at the pumps. Most die in the process. • On average, over 9 million fish – representing the twenty fish species considered in this report – are “salvaged” each year at the pumps. As many as 15 million fish of all species encountered are “salvaged” each year. • Up to 40% of the total population of the endangered delta smelt and 15% of the endangered winter-run population of Chinook salmon are killed at the pumps in some years. In the first half of 2011, over 8.6 million splittail were salvaged. • Salvage estimates drastically underestimate the problem. The numbers do not factor in the results of “indirect” mortality, as high levels of export pumping disrupt fish migration, shrink the amount of non-lethal habitat available to fish species, and remove vast amounts of biomass, including fish eggs and larvae too small to be screened at the pumps. • Export pumping causes the lower San Joaquin River to flow backwards most of the year and removes the equivalent of 170 railroad boxcars of water – and the accompanying fish, other organisms, and nutrients – from the Delta ecosystem every minute. • Large numbers of fish being entrained is a problem even for species that are not currently listed as “endangered.” Killing large numbers of fish year after year cuts off population growth in response to favorable conditions and can start the species on a downward path to extinction. As the species declines, the population impacts of entrainment become proportionately larger. • Entrainment is a real problem. But the same interests in the Delta export community who claim that it isn’t also back constructing expensive new conveyance facilities such as a peripheral canal or tunnel to solve the problem that they say doesn’t exist.

Colorado River Aqueduct Recording Project 1998

National Park Service (NPS) | December 15th, 1988

The Colorado River Aqueduct Recording Project is part of the Historic American Engineering Record (HAER), a long-range program that documents historically-significant eng

The Colorado River Aqueduct Recording Project is part of the Historic American Engineering Record (HAER), a long-range program that documents historically-significant engineering, industrial, and maritime sites In the United States. The HAER program is administered by the Historic American Buildings Survey / Historic American Engineering Record (HABS/HAER) Division of the National Park Service. U.S. Department of the Interior. The recording project was co-sponsored during the summer of 1998 by HABS/HAER under the general direction of E. Blaine Oliver, Chief; and by the Metropolitan Water District of Southern California, Gary M. Snyder, Chief Engineer, and Wally M. Lieu, Assistant Chief Engineer. The measured drawings, historical report, and photographs were prepared under the direction of Eric N. DeLony, Chief of HAER, The recording team included Supervisory Architect Andrew Johnston (University of California, Berkeley) and architects Chrysti Chun (Illinois Institute of Technology), Imola Klrlzsa'n (ICOMOS, Romania), Sydney Mainster (University of California, Berkeley), Elizabeth Mllnarik (University of Illinois, Urbana-Champaign), and Nina Shatberashvili (ICOMOS, Republic of Georgia); Project Historian J. Philip Gruen (University of California, Berkeley); and photographer Jet Lowe (Washington, D. C.) Additional drawings were provided by architects Christopher B. Brown (University of Washington) and Adrim Maksay (Transylvania Trust Foundation, Romania). Engineer Allien Whitsett (Metropolitan Water District of Southern California) provided consultation and advice. Devon Kobayashi (Metropolitan Water District of Southern California) served as HAER liaison.

Colorado River Aqueduct Route Selected for Metropolitan Water District Requires Pumping

Civil Engineering | February 10th, 1931