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132-492: The precipitation in the northern part of the state, vital to the health of watersheds, fisheries, and communities in Northern California and often impacted by climate change and drought, has long been diverted by federal and state water projects to the somewhat drier southern portion of the state for agriculture and urban use. In the 1960s, Governor Pat Brown supported two large projects that reallocated water from

264-703: A 50-year span. The US Fish and Wildlife Service said it would not issue permits for the plan because the state could not prove that the habitat restoration project would help the salmon , sturgeon , or delta smelt . As a result, the Brown administration drastically reduced the habitat restoration plan and separated the water supply improvement plan, renaming it the WaterFix and EcoRestore project. The revised plan proposes short-term permits for each endangered species encountered. The EcoRestore project only attempts to restore 30,000 acres (12,000 ha) over five years at

396-527: A comprehensive benefit-cost analysis conducted by the University of the Pacific 's Center for Business and Policy Research found that the project provided 23 cents in benefit for every dollar spent, or in the most optimistic scenario, 39 cents per dollar. Economist Jeffrey Michael, a professor of policy at the university, wrote that the project would deliver too little additional water for the cost. The study

528-637: A cost of $ 300 million, funded with state bond money and other sources. The WaterFix project was proposed to address the issues of the water system infrastructure in California being "unreliable and outdated". The proposal also prepares for possible threats to the water system such as climate change and seismic activity. Currently, water is exported from the Sacramento-San Joaquin Delta to the State Water Project and

660-642: A decadal timescale. Other changes are caused by an imbalance of energy from external forcings . Examples of these include changes in the concentrations of greenhouse gases , solar luminosity , volcanic eruptions, and variations in the Earth's orbit around the Sun. To determine the human contribution to climate change, unique "fingerprints" for all potential causes are developed and compared with both observed patterns and known internal climate variability . For example, solar forcing—whose fingerprint involves warming

792-473: A decrease in total water conveyance capacity available within the canal. No major negative impacts to the integrity of the structure of the canal have been noted, though minor issues requiring additional maintenance have been report. The U.S. Department of the Interior , Bureau of Reclamation evaluated the ability to improve water quality, energy consumption and production, productive fisheries, and flow to

924-489: A district court did decide that it was legal for the water district to purchase these islands because there are no negative impacts of their purchase as of yet. Climate change Present-day climate change includes both global warming —the ongoing increase in global average temperature —and its wider effects on Earth's climate . Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures

1056-542: A lot of light to being dark after the ice has melted, they start absorbing more heat . Local black carbon deposits on snow and ice also contribute to Arctic warming. Arctic surface temperatures are increasing between three and four times faster than in the rest of the world. Melting of ice sheets near the poles weakens both the Atlantic and the Antarctic limb of thermohaline circulation , which further changes

1188-412: A marked increase in temperature. Ongoing changes in climate have had no precedent for several thousand years. Multiple independent datasets all show worldwide increases in surface temperature, at a rate of around 0.2 °C per decade. The 2014–2023 decade warmed to an average 1.19 °C [1.06–1.30 °C] compared to the pre-industrial baseline (1850–1900). Not every single year was warmer than

1320-408: A physical climate model. These models simulate how population, economic growth , and energy use affect—and interact with—the physical climate. With this information, these models can produce scenarios of future greenhouse gas emissions. This is then used as input for physical climate models and carbon cycle models to predict how atmospheric concentrations of greenhouse gases might change. Depending on

1452-461: A result of climate change. Global sea level is rising as a consequence of thermal expansion and the melting of glaciers and ice sheets . Sea level rise has increased over time, reaching 4.8 cm per decade between 2014 and 2023. Over the 21st century, the IPCC projects 32–62 cm of sea level rise under a low emission scenario, 44–76 cm under an intermediate one and 65–101 cm under

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1584-474: A result. The World Health Organization calls climate change one of the biggest threats to global health in the 21st century. Societies and ecosystems will experience more severe risks without action to limit warming . Adapting to climate change through efforts like flood control measures or drought-resistant crops partially reduces climate change risks, although some limits to adaptation have already been reached. Poorer communities are responsible for

1716-417: A small share of global emissions , yet have the least ability to adapt and are most vulnerable to climate change . Many climate change impacts have been observed in the first decades of the 21st century, with 2023 the warmest on record at +1.48 °C (2.66 °F) since regular tracking began in 1850. Additional warming will increase these impacts and can trigger tipping points , such as melting all of

1848-616: A study of Delta smelt in 2015, and found only six in the study area, where prior surveys netted hundreds. The Water Fix plan does not provide any guarantee as to how much water the project would produce each year. When the Bay Conservation Development Plan was dropped, so was the 50-year plan. The current plan relies on a year-to-year environmental permits, which causes uncertainty about the plan's ability to fulfill its purpose. Environmental groups are unanimously opposed to and/or have voiced strong concerns about

1980-547: A tunnel that would take water from the Sacramento River and would bypass the Sacramento-San Joaquin Delta, taking water to Bethany Reservoir, then to the California Aqueduct. The 2022 plan was scaled-down from earlier proposals, and consists of a single concrete tunnel with a diameter of 36 feet, built 140 to 170 feet underground. Gov. Newsom is supporting the project. On December 21, 2023, the project

2112-548: A very high emission scenario. Marine ice sheet instability processes in Antarctica may add substantially to these values, including the possibility of a 2-meter sea level rise by 2100 under high emissions. Climate change has led to decades of shrinking and thinning of the Arctic sea ice . While ice-free summers are expected to be rare at 1.5 °C degrees of warming, they are set to occur once every three to ten years at

2244-519: A warming level of 2 °C. Higher atmospheric CO 2 concentrations cause more CO 2 to dissolve in the oceans, which is making them more acidic . Because oxygen is less soluble in warmer water, its concentrations in the ocean are decreasing , and dead zones are expanding. Greater degrees of global warming increase the risk of passing through ' tipping points '—thresholds beyond which certain major impacts can no longer be avoided even if temperatures return to their previous state. For instance,

2376-512: Is driven by human activities , especially fossil fuel burning since the Industrial Revolution . Fossil fuel use, deforestation , and some agricultural and industrial practices release greenhouse gases . These gases absorb some of the heat that the Earth radiates after it warms from sunlight , warming the lower atmosphere. Carbon dioxide , the primary greenhouse gas driving global warming, has grown by about 50% and

2508-601: Is a 117-mile-long (188 km) aqueduct in central California , United States . The canal was designed and completed in 1951 by the U.S. Bureau of Reclamation as part of the Central Valley Project . It carries freshwater to replace San Joaquin River water which is diverted into the Madera Canal and Friant-Kern Canal at Friant Dam . The canal begins at the C.W. Bill Jones Pumping Plant (formerly

2640-715: Is a SWP contractor and one of the largest players in California water politics, serving 19 million urban residents. It is one of the tunnels' strongest supporters. According to the Metropolitan Water District , southern California receives about 30 percent of its water supply from delta sources originating in snowmelt from the Sierra Nevada. In 2014, the state proposed that customers of the project would make billions of dollars in annual fixed payments, even during drought periods when water deliveries would drop or even cease. The state treasurer's office said

2772-460: Is a wholesale water provider that delivers CVP largely to farmers covering 2,100,000 acres (850,000 ha) in 29 separate districts. It received no CVP water in 2014 and 2015. The Kern County Water Agency is a SWP contractor serving 674,000 acres (273,000 ha). It received 20% of its normal SWP allotment in 2015. The powerful Westlands Water District is the largest member of San Luis Authority. The Metropolitan Water District of Southern California

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2904-564: Is an estimated total sea level rise of 2.3 metres per degree Celsius (4.2 ft/°F) after 2000 years. Oceanic CO 2 uptake is slow enough that ocean acidification will also continue for hundreds to thousands of years. Deep oceans (below 2,000 metres (6,600 ft)) are also already committed to losing over 10% of their dissolved oxygen by the warming which occurred to date. Further, the West Antarctic ice sheet appears committed to practically irreversible melting, which would increase

3036-509: Is as big or bigger than the English Channel Tunnel and Boston's Big Dig . The project would also include three new intakes with a capacity of 9000 cubic feet per second (approx. 255 kilolitres per second) each, and a total annual yield of 4.9 million acre-feet . The proposed cost for the tunnels is $ 15 billion, with $ 8 billion additional devoted to habitat restoration . The project was to be funded by revenue bonds created by

3168-488: Is at levels not seen for millions of years. Climate change has an increasingly large impact on the environment . Deserts are expanding , while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has contributed to thawing permafrost , retreat of glaciers and sea ice decline . Higher temperatures are also causing more intense storms , droughts, and other weather extremes . Rapid environmental change in mountains , coral reefs , and

3300-551: Is believed due to poor water quality, increased water pollution, changes in water operations, and change of water demands for the various water users. Due to those reasons, physical improvements and changes in procedure are being made. Land subsidence is prevalent throughout the San Joaquin Valley, but was unrecognized prior to the construction of the canal. After construction, discrepancies in elevation were believed to be caused by earthquake. Post construction years,

3432-711: Is determined by modelling the carbon cycle and climate sensitivity to greenhouse gases. According to UNEP , global warming can be kept below 1.5 °C with a 50% chance if emissions after 2023 do not exceed 200 gigatonnes of CO 2 . This corresponds to around 4 years of current emissions. To stay under 2.0 °C, the carbon budget is 900 gigatonnes of CO 2 , or 16 years of current emissions. The climate system experiences various cycles on its own which can last for years, decades or even centuries. For example, El Niño events cause short-term spikes in surface temperature while La Niña events cause short term cooling. Their relative frequency can affect global temperature trends on

3564-399: Is independent of where greenhouse gases are emitted, because the gases persist long enough to diffuse across the planet. Since the pre-industrial period, the average surface temperature over land regions has increased almost twice as fast as the global average surface temperature. This is because oceans lose more heat by evaporation and oceans can store a lot of heat . The thermal energy in

3696-745: Is mandated out of the Sacramento-San Joaquin Delta . If the bill is passed there will be no mitigation for the damage that may occur along the San Joaquin river or in the Delta due to the California Water Fix. Another bill that may change the fate of the California Water Fix and Eco Restore is Assembly Bill 1713 If passed, it would require California voters to approve the Water Fix and Eco Restore. The basis for

3828-450: Is primarily attributed to sulfate aerosols produced by the combustion of fossil fuels with heavy sulfur concentrations like coal and bunker fuel . Smaller contributions come from black carbon (from combustion of fossil fuels and biomass), and from dust. Globally, aerosols have been declining since 1990 due to pollution controls, meaning that they no longer mask greenhouse gas warming as much. Aerosols also have indirect effects on

3960-444: Is radiating into space. Warming reduces average snow cover and forces the retreat of glaciers . At the same time, warming also causes greater evaporation from the oceans , leading to more atmospheric humidity , more and heavier precipitation . Plants are flowering earlier in spring, and thousands of animal species have been permanently moving to cooler areas. Different regions of the world warm at different rates . The pattern

4092-504: Is released into the canal. The Delta–Mendota Canal ends at Mendota Pool, on the San Joaquin River near the city of Mendota , 30 mi (48 km) west of Fresno . The Delta–Mendota Canal capacity is 4,600 cu ft/s (130 m /s) and gradually decreases to 3,211 cu ft/s (90.9 m /s) at its terminus. Average annual throughput is 1,993,000 acre-feet (2.458 km ). In order to improve water delivery in

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4224-516: Is shaped by feedbacks, which either amplify or dampen the change. Self-reinforcing or positive feedbacks increase the response, while balancing or negative feedbacks reduce it. The main reinforcing feedbacks are the water-vapour feedback , the ice–albedo feedback , and the net effect of clouds. The primary balancing mechanism is radiative cooling , as Earth's surface gives off more heat to space in response to rising temperature. In addition to temperature feedbacks, there are feedbacks in

4356-407: Is the major reason why different climate models project different magnitudes of warming for a given amount of emissions. A climate model is a representation of the physical, chemical and biological processes that affect the climate system. Models include natural processes like changes in the Earth's orbit, historical changes in the Sun's activity, and volcanic forcing. Models are used to estimate

4488-504: Is to protect aquatic fauna from being injured or killed by the pumps that facilitate water to the south of the state. The facility is roughly 1 km east from the Pumping Plant, and became operational 1957. Most common fish species safely moved through the series of louvers are American shad, Splittail, White Catfish, Delta smelt, Chinook salmon, and Striped bass. Historical trends show a decrease in efficient fish diversion, and it

4620-417: Is unclear. A related phenomenon driven by climate change is woody plant encroachment , affecting up to 500 million hectares globally. Climate change has contributed to the expansion of drier climate zones, such as the expansion of deserts in the subtropics . The size and speed of global warming is making abrupt changes in ecosystems more likely. Overall, it is expected that climate change will result in

4752-401: Is viewed by ecologists as an important way to promote the recovery of an ecosystem. The California Water Fix was subject to a biological assessment, which is required for any project that has the potential of having an impact on the environment. The adjacent table shows a page from the biological assessment which lists threatened and endangered species that have the potential of being affected by

4884-511: The Atlantic meridional overturning circulation (AMOC), and irreversible damage to key ecosystems like the Amazon rainforest and coral reefs can unfold in a matter of decades. The long-term effects of climate change on oceans include further ice melt, ocean warming , sea level rise, ocean acidification and ocean deoxygenation. The timescale of long-term impacts are centuries to millennia due to CO 2 's long atmospheric lifetime. The result

5016-661: The Earth's energy budget . Sulfate aerosols act as cloud condensation nuclei and lead to clouds that have more and smaller cloud droplets. These clouds reflect solar radiation more efficiently than clouds with fewer and larger droplets. They also reduce the growth of raindrops , which makes clouds more reflective to incoming sunlight. Indirect effects of aerosols are the largest uncertainty in radiative forcing . While aerosols typically limit global warming by reflecting sunlight, black carbon in soot that falls on snow or ice can contribute to global warming. Not only does this increase

5148-573: The Greenland ice sheet is already melting, but if global warming reaches levels between 1.7 °C and 2.3 °C, its melting will continue until it fully disappears. If the warming is later reduced to 1.5 °C or less, it will still lose a lot more ice than if the warming was never allowed to reach the threshold in the first place. While the ice sheets would melt over millennia, other tipping points would occur faster and give societies less time to respond. The collapse of major ocean currents like

5280-840: The Greenland ice sheet . Under the 2015 Paris Agreement , nations collectively agreed to keep warming "well under 2 °C". However, with pledges made under the Agreement, global warming would still reach about 2.8 °C (5.0 °F) by the end of the century. Limiting warming to 1.5 °C would require halving emissions by 2030 and achieving net-zero emissions by 2050. Fossil fuel use can be phased out by conserving energy and switching to energy sources that do not produce significant carbon pollution. These energy sources include wind , solar , hydro , and nuclear power . Cleanly generated electricity can replace fossil fuels for powering transportation , heating buildings , and running industrial processes. Carbon can also be removed from

5412-635: The Industrial Revolution , naturally-occurring amounts of greenhouse gases caused the air near the surface to be about 33 °C warmer than it would have been in their absence. Human activity since the Industrial Revolution, mainly extracting and burning fossil fuels ( coal , oil , and natural gas ), has increased the amount of greenhouse gases in the atmosphere. In 2022, the concentrations of CO 2 and methane had increased by about 50% and 164%, respectively, since 1750. These CO 2 levels are higher than they have been at any time during

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5544-470: The San Joaquin River with the use of recirculation strategies using the Central Valley Project facilities. The Recirculation Feasibility Study Project was authorized by CALFED (California Federal Bay-Delta Program) Bay-Delta Authorization Act of 2004 (118 Stat. §§ 1681–1702.; Public Law 108-361). History has shown that low precipitation patterns can lead to pumping stations reversing the flow in

5676-690: The San Luis Delta Mendota Water Authority are responsible for maintaining the water quality that is discharged at the south end of the canal. The Delta–Mendota Canal is also a key feature to the Delta Division Project which is managed by the Bureau of Reclamation, to minimize salt intrusion from the San Francisco Bay. Due to the length of the canal, it required several contracts to complete

5808-518: The World Economic Forum , 14.5 million more deaths are expected due to climate change by 2050. 30% of the global population currently live in areas where extreme heat and humidity are already associated with excess deaths. By 2100, 50% to 75% of the global population would live in such areas. While total crop yields have been increasing in the past 50 years due to agricultural improvements, climate change has already decreased

5940-414: The carbon cycle . While plants on land and in the ocean absorb most excess emissions of CO 2 every year, that CO 2 is returned to the atmosphere when biological matter is digested, burns, or decays. Land-surface carbon sink processes, such as carbon fixation in the soil and photosynthesis, remove about 29% of annual global CO 2 emissions. The ocean has absorbed 20 to 30% of emitted CO 2 over

6072-402: The climate system . Solar irradiance has been measured directly by satellites , and indirect measurements are available from the early 1600s onwards. Since 1880, there has been no upward trend in the amount of the Sun's energy reaching the Earth, in contrast to the warming of the lower atmosphere (the troposphere ). The upper atmosphere (the stratosphere ) would also be warming if the Sun

6204-971: The extinction of many species. The oceans have heated more slowly than the land, but plants and animals in the ocean have migrated towards the colder poles faster than species on land. Just as on land, heat waves in the ocean occur more frequently due to climate change, harming a wide range of organisms such as corals, kelp , and seabirds . Ocean acidification makes it harder for marine calcifying organisms such as mussels , barnacles and corals to produce shells and skeletons ; and heatwaves have bleached coral reefs . Harmful algal blooms enhanced by climate change and eutrophication lower oxygen levels, disrupt food webs and cause great loss of marine life. Coastal ecosystems are under particular stress. Almost half of global wetlands have disappeared due to climate change and other human impacts. Plants have come under increased stress from damage by insects. The effects of climate change are impacting humans everywhere in

6336-432: The socioeconomic scenario and the mitigation scenario, models produce atmospheric CO 2 concentrations that range widely between 380 and 1400 ppm. The environmental effects of climate change are broad and far-reaching, affecting oceans , ice, and weather. Changes may occur gradually or rapidly. Evidence for these effects comes from studying climate change in the past, from modelling, and from modern observations. Since

6468-605: The $ 25 billion financing plan would only be possible if water agencies adopted a set yearly payment plan. The State Treasurer's Office released a study in November 2014 conducted by consultants who found the project was feasible. According to the plan, the cities, water agencies—including an estimated 25 million residents—and farmers of 3 million acres, not taxpayers, would be responsible for the billions of dollars in debt over 50 years, even during dry years while receiving little or no water. The Metropolitan Water District has stated that

6600-405: The 18th century and 1970 there was little net warming, as the warming impact of greenhouse gas emissions was offset by cooling from sulfur dioxide emissions. Sulfur dioxide causes acid rain , but it also produces sulfate aerosols in the atmosphere, which reflect sunlight and cause global dimming . After 1970, the increasing accumulation of greenhouse gases and controls on sulfur pollution led to

6732-612: The 1950s, droughts and heat waves have appeared simultaneously with increasing frequency. Extremely wet or dry events within the monsoon period have increased in India and East Asia. Monsoonal precipitation over the Northern Hemisphere has increased since 1980. The rainfall rate and intensity of hurricanes and typhoons is likely increasing , and the geographic range likely expanding poleward in response to climate warming. Frequency of tropical cyclones has not increased as

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6864-530: The 1970s. It has 600 miles (970 km) of canals and moves up to 13 million acre feet per year and generates electricity—about half of which is used by the system. Overall, depending on the weather and amount of rain, up to 80% of water in the state is used for agriculture. Before the Central Valley Project Improvement Act (CVPIA) in 1992, the water transported from northern California went primarily to agriculture (90%), with

6996-500: The 1980s, the terms global warming and climate change became more common, often being used interchangeably. Scientifically, global warming refers only to increased surface warming, while climate change describes both global warming and its effects on Earth's climate system , such as precipitation changes. Climate change can also be used more broadly to include changes to the climate that have happened throughout Earth's history. Global warming —used as early as 1975 —became

7128-464: The 5 to 7 million acre-feet (6.2 to 8.6 km) of water being removed from the delta each year for delivery to the Central Valley and Southern California . The WaterFix proposal included two categories of construction: the north tunnels and the main tunnels. The north tunnels were to be three separate tunnels, each about 14 miles long, which would connect the three intake facilities to

7260-440: The Arctic is forcing many species to relocate or become extinct . Even if efforts to minimize future warming are successful, some effects will continue for centuries. These include ocean heating , ocean acidification and sea level rise . Climate change threatens people with increased flooding , extreme heat, increased food and water scarcity, more disease, and economic loss . Human migration and conflict can also be

7392-435: The Arctic is another major feedback, this reduces the reflectivity of the Earth's surface in the region and accelerates Arctic warming . This additional warming also contributes to permafrost thawing, which releases methane and CO 2 into the atmosphere. Around half of human-caused CO 2 emissions have been absorbed by land plants and by the oceans. This fraction is not static and if future CO 2 emissions decrease,

7524-545: The CO 2 released by the chemical reactions for making cement , steel , aluminum , and fertilizer . Methane emissions come from livestock , manure, rice cultivation , landfills, wastewater, and coal mining , as well as oil and gas extraction . Nitrous oxide emissions largely come from the microbial decomposition of fertilizer . While methane only lasts in the atmosphere for an average of 12 years, CO 2 lasts much longer. The Earth's surface absorbs CO 2 as part of

7656-613: The California Delta, North Coast Rivers Alliance, Water4Fish, AquAlliance, and various Sierra Club chapters. Cities in and near the Delta and farmers in the delta are also opposed to the project because it would worsen the quality of water available for local municipal and agricultural uses. The project would also require filling of 775 acres of wetlands and entail over a decade of construction. In January 2024, San Francisco Baykeeper, California Indian Environmental Alliance, Golden State Salmon Association, The Bay Institute, Restore

7788-898: The Central Valley Project. The water flows through a maze of river channels and sloughs before entering the Clifton Court Forebay north of Tracy . From here, the Banks Pumping Plant pumps water into the California Aqueduct and the South Bay Aqueduct ; the nearby C.W. Bill Jones Pumping Plant pumps water into the Delta-Mendota Canal . If not diverted, the water would flow into San Francisco Bay . The freshwater/saltwater gradient has moved inland because of

7920-534: The City of San Francisco, in the rural community of Byron, California, near the city of Tracy. Water is extracted from the southern portion of the San Joaquin Delta, and pumped to contractors in the San Joaquin Valley, San Benito and Santa Clara counties to meet urban and agricultural demands. With the use of two 15 foot diameter pipes, six 22,500-horsepower motors, roughly 8,500 Acre-feet (AF) of water from

8052-616: The Columbia Pumping Plant, Mowry Pumping Plant, United Concrete Pipe Corporation, Western Contracting Corporation, A. Teichert & Sons, Inc. General work shifts consisted of 3 daily shifts, twenty-one hours a day, 6 days a week. The pumping plants in the Delta Division have serious impacts on the flow of the Delta and San Joaquin River Basin. During relatively dry years and a high exportation rate, flow of

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8184-628: The Delta Field Division Operations and Maintenance Center as well as to the Joint Operations Center in Sacramento. Though the WaterFix proposal aims to resolve some issues with the California water system, there are many it does not address. The plan does not consider the possibility that there could be less flow in the Sacramento River, nor does it address how to allocate water to fisheries found in

8316-475: The Delta area. The proposal details the planning and construction of the project. It provides that the Department of Water Resources enters a contract with the project manager for the WaterFix and a program director will coordinate with the department. Managing the project would be a board of directors known as the "Authority Board", which would receive and review monthly status updates on the construction of

8448-590: The Delta can be transported southward daily, after being lifted nearly 200 feet. The plant is named to honor a pioneer in water management for the San Joaquin Valley, and was president of the San Luis and Delta-Mendota Water Association for two decades. The water is pumped from the canal into O'Neill Forebay , and then is pumped into San Luis Reservoir by the Gianelli Pumping-Generating Plant. Occasionally, water from O'Neill Forebay

8580-716: The Delta, and the Shingle Springs Band of Miwok Indians filed litigation against the Delta Conveyance project. In the lawsuit, the groups assert that the California Department of Water Resources violated the California Environmental Quality Act (CEQA) by failing to address numerous negative effects the project would have on fish populations, other wildlife, and Native American Tribes . A second lawsuit

8712-500: The Delta, some of which are already struggling because of current water exports from the Delta. There are also no plans to deal with the extreme subsidence that is happening in the Delta. In May of 2019, the Department of Water Resources withdrew the proposed permits for the WaterFix project, conducting a new environmental review, and began the planning processes for a significantly smaller singular tunnel project that would replace

8844-604: The Earth will be able to absorb up to around 70%. If they increase substantially, it'll still absorb more carbon than now, but the overall fraction will decrease to below 40%. This is because climate change increases droughts and heat waves that eventually inhibit plant growth on land, and soils will release more carbon from dead plants when they are warmer . The rate at which oceans absorb atmospheric carbon will be lowered as they become more acidic and experience changes in thermohaline circulation and phytoplankton distribution. Uncertainty over feedbacks, particularly cloud cover,

8976-636: The Intermediate Forebay (IF). The main tunnels were intended to connect the Intermediate Forebay to the Clifton Court Forebay . These twin tunnels, depicted in the adjacent image, would be about 30 miles long. The main tunnels were also known as the twin tunnels, but were different from the Peripheral Canals proposed in 1982. The WaterFix was intended to make conveyance of water for the State Water Project and Central Valley Project more reliable while relieving environmental pressure on

9108-531: The San Joaquin River has been reversed. This flow reversal confuses migratory fish, and brings saline water. An important feature of the Central Valley Project , with regards to directing water southward through the Delta–Mendota Canal is the C.W. Bill Jones Pumping Plant , formerly known as the Tracy Pumping Plant (TPP). The pumping station is 60 miles (96 km) to the southeast from

9240-703: The San Joaquin River watershed's water to flow through into the delta during the winter and spring months. Current rules allow the pumps to suck as much as 90 percent of the water from the river into the canals for Southern California's use. Even though environmental regulations bar pumping under certain conditions, the pumping has pulled migrating fish away from their intended destinations. The formerly large populations of Delta smelt, Chinook salmon and other native fish have dropped to historically low levels. At least 35 native fish, plants and animal species have been added to federal and state endangered-species lists. The Delta smelt may be near extinction. State biologists conducted

9372-608: The State of California, an intertie, which is defined as a connection between 2 or more current utilities, was constructed between the Delta–Mendota Canal and the California Aqueduct . The Intertie was constructed in the rural agricultural region of the southwestern portion of the San Joaquin Valley in Alameda County, near the city of Tracy , California. A series of two 108 inch diameter pipes of 500 feet in length connect

9504-765: The Tracy Pumping Plant). Water is lifted 197 ft (60 m) from the Sacramento-San Joaquin Delta at the Clifton Court Forebay . The canal runs southward along the western edge of the San Joaquin Valley , parallel to the California Aqueduct , and diverges to the east after passing the San Luis Reservoir , receiving more water and eventually emptying into the San Joaquin River near the city of Mendota . The canal travels through six California counties: Alameda, San Joaquin, Stanislaus, Merced, and Fresno counties. After years of drought,

9636-486: The Water Fix. The "Authority Board" has a "Program Advisory Group" to advise board members, made up of technical experts from the Department of Water Resources. The director of the Department of Water Resources would have final control of all aspects of the project. To control and monitor each of the facilities the proposal includes a Supervisory Control and Data Acquisition ( SCADA ) system at each location which can be controlled locally or remotely. The system would connect to

9768-669: The WaterFix project. In March 2016, the Securities and Exchange Commission assessed a rare fine on Westlands in a settlement for misleading bond investors about the impact that the drought and water cuts had on its revenues. Their action raised concern about their ability to finance the WaterFix project. After Westlands was fined for its questionable spending and accounting practices, the Joint Legislative Audit Committee in August 2016 requested an audit of

9900-691: The WaterFix project. This project will help prevent rising sea-levels and salt water from intruding in the Delta, giving the water supply more reliability while maintaining limited impacts on the communities and fish that rely on the Delta. The Eco Restore plan is to mitigate the effects the California Water Fix will have on the environment either through construction or operation. The planned Eco Restore includes upwards of 30,000 acres (12,000 ha) for restoration; 1,000 acres (400 ha) will be for upland and habitat protection linked to flood protection, 3,500 acres (1,400 ha) for wetland restoration, 9,000 acres (3,600 ha) for tidal and sub tidal zones, and

10032-441: The absorption of sunlight, it also increases melting and sea-level rise. Limiting new black carbon deposits in the Arctic could reduce global warming by 0.2 °C by 2050. The effect of decreasing sulfur content of fuel oil for ships since 2020 is estimated to cause an additional 0.05 °C increase in global mean temperature by 2050. As the Sun is the Earth's primary energy source, changes in incoming sunlight directly affect

10164-574: The agencies who benefit, and paid by the farmers and urban water users who benefit from the project, not taxpayers as a whole, and thus not requiring legislative or voter approval. However, an audit by the U.S. Department of the Interior released in September 2017 revealed that $ 50 million of the taxpayers' money was funneled into the project. In 2022, the project was re-named to the Delta Conveyance Project. It continued to propose

10296-518: The amount of electricity it generates. The water transported by the State Water Project is divided 75% for urban use and 25% for agriculture. When Governor Jerry Brown was previously in office, he championed an earlier version of the tunnels project called the Peripheral Canal. It would have transported water from near Sacramento around the Sacramento-San Joaquin Delta into the Central Valley Project and exported it to southern California. It

10428-443: The annual payment plan is required to sell revenue bonds at reasonable rates. But several of the agencies who would be required to pay for the construction project have stated they can't justify the costs if there's a chance they'll end up with less water. On November 8, 2016, California voters defeated Proposition 53, which would have required a public vote on any projects backed by state-issued revenue bonds over $ 2 billion, including

10560-411: The atmosphere , for instance by increasing forest cover and farming with methods that capture carbon in soil . Before the 1980s it was unclear whether the warming effect of increased greenhouse gases was stronger than the cooling effect of airborne particulates in air pollution . Scientists used the term inadvertent climate modification to refer to human impacts on the climate at this time. In

10692-452: The atmosphere. volcanic CO 2 emissions are more persistent, but they are equivalent to less than 1% of current human-caused CO 2 emissions. Volcanic activity still represents the single largest natural impact (forcing) on temperature in the industrial era. Yet, like the other natural forcings, it has had negligible impacts on global temperature trends since the Industrial Revolution. The climate system's response to an initial forcing

10824-454: The biggest threats to global health in the 21st century. Scientists have warned about the irreversible harms it poses. Extreme weather events affect public health, and food and water security . Temperature extremes lead to increased illness and death. Climate change increases the intensity and frequency of extreme weather events. It can affect transmission of infectious diseases , such as dengue fever and malaria . According to

10956-540: The carbon cycle, such as the fertilizing effect of CO 2 on plant growth. Feedbacks are expected to trend in a positive direction as greenhouse gas emissions continue, raising climate sensitivity. These feedback processes alter the pace of global warming. For instance, warmer air can hold more moisture in the form of water vapour , which is itself a potent greenhouse gas. Warmer air can also make clouds higher and thinner, and therefore more insulating, increasing climate warming. The reduction of snow cover and sea ice in

11088-551: The climate cycled through ice ages . One of the hotter periods was the Last Interglacial , around 125,000 years ago, where temperatures were between 0.5 °C and 1.5 °C warmer than before the start of global warming. This period saw sea levels 5 to 10 metres higher than today. The most recent glacial maximum 20,000 years ago was some 5–7 °C colder. This period has sea levels that were over 125 metres (410 ft) lower than today. Temperatures stabilized in

11220-534: The construction. The first contracts given by the Bureau of Reclamation were awarded on June 14, 1946, to Hubert H. Everist for station 686+00-1365+00, and workers went on strike against the subcontractor Fred J. Maurer and Son. The next series of contracts were awarded on October 24, 1946 to the Morrison Knudsen Company, Inc., and the M.H. Hasler Construction Company, who worked on the stations 185+00-231+00 and 243+00-774+00. Other contractors were

11352-684: The current interglacial period beginning 11,700 years ago . This period also saw the start of agriculture. Historical patterns of warming and cooling, like the Medieval Warm Period and the Little Ice Age , did not occur at the same time across different regions. Temperatures may have reached as high as those of the late 20th century in a limited set of regions. Climate information for that period comes from climate proxies , such as trees and ice cores . Around 1850 thermometer records began to provide global coverage. Between

11484-403: The degree of warming future emissions will cause when accounting for the strength of climate feedbacks . Models also predict the circulation of the oceans, the annual cycle of the seasons, and the flows of carbon between the land surface and the atmosphere. The physical realism of models is tested by examining their ability to simulate current or past climates. Past models have underestimated

11616-427: The destroyed trees release CO 2 , and are not replaced by new trees, removing that carbon sink . Between 2001 and 2018, 27% of deforestation was from permanent clearing to enable agricultural expansion for crops and livestock. Another 24% has been lost to temporary clearing under the shifting cultivation agricultural systems. 26% was due to logging for wood and derived products, and wildfires have accounted for

11748-401: The distribution of heat and precipitation around the globe. The World Meteorological Organization estimates there is an 80% chance that global temperatures will exceed 1.5 °C warming for at least one year between 2024 and 2028. The chance of the 5-year average being above 1.5 °C is almost half. The IPCC expects the 20-year average global temperature to exceed +1.5 °C in

11880-444: The dominant direct influence on temperature from land use change. Thus, land use change to date is estimated to have a slight cooling effect. Air pollution, in the form of aerosols, affects the climate on a large scale. Aerosols scatter and absorb solar radiation. From 1961 to 1990, a gradual reduction in the amount of sunlight reaching the Earth's surface was observed. This phenomenon is popularly known as global dimming , and

12012-610: The early 2030s. The IPCC Sixth Assessment Report (2021) included projections that by 2100 global warming is very likely to reach 1.0–1.8 °C under a scenario with very low emissions of greenhouse gases , 2.1–3.5 °C under an intermediate emissions scenario , or 3.3–5.7 °C under a very high emissions scenario . The warming will continue past 2100 in the intermediate and high emission scenarios, with future projections of global surface temperatures by year 2300 being similar to millions of years ago. The remaining carbon budget for staying beneath certain temperature increases

12144-639: The eastern parts of the Central Valley, however, altered the natural flows of the San Joaquin River between the Friant Dam and confluence of the Merced River.  The Delta–Mendota Canal was approved for the exchange of water rights in the downstream portion of the San Joaquin River. With the use of the Tracy Pumping Plant, water from the Sacramento River would be diverted into the Delta–Mendota Canal. The United States Bureau of Reclamation and

12276-831: The emissions continue to increase for the rest of century, then over 9 million climate-related deaths would occur annually by 2100. Economic damages due to climate change may be severe and there is a chance of disastrous consequences. Severe impacts are expected in South-East Asia and sub-Saharan Africa , where most of the local inhabitants are dependent upon natural and agricultural resources. Heat stress can prevent outdoor labourers from working. If warming reaches 4 °C then labour capacity in those regions could be reduced by 30 to 50%. The World Bank estimates that between 2016 and 2030, climate change could drive over 120 million people into extreme poverty without adaptation. Delta-Mendota Canal The Delta–Mendota Canal

12408-430: The entire atmosphere—is ruled out because only the lower atmosphere has warmed. Atmospheric aerosols produce a smaller, cooling effect. Other drivers, such as changes in albedo , are less impactful. Greenhouse gases are transparent to sunlight , and thus allow it to pass through the atmosphere to heat the Earth's surface. The Earth radiates it as heat , and greenhouse gases absorb a portion of it. This absorption slows

12540-604: The global climate system has grown with only brief pauses since at least 1970, and over 90% of this extra energy has been stored in the ocean . The rest has heated the atmosphere , melted ice, and warmed the continents. The Northern Hemisphere and the North Pole have warmed much faster than the South Pole and Southern Hemisphere . The Northern Hemisphere not only has much more land, but also more seasonal snow cover and sea ice . As these surfaces flip from reflecting

12672-474: The implementation of the California Water Fix. The table shows that three species of threatened or endangered species of salmon, trout and sturgeon will likely be adversely affected by the project, one over a large area. There are currently 12 environmental commitments that are included in the proposal for the Eco Restore. The Bay Delta Conservation Plan proposal before this included similar mitigation under

12804-572: The last 14 million years. Concentrations of methane are far higher than they were over the last 800,000 years. Global human-caused greenhouse gas emissions in 2019 were equivalent to 59 billion tonnes of CO 2 . Of these emissions, 75% was CO 2 , 18% was methane , 4% was nitrous oxide, and 2% was fluorinated gases . CO 2 emissions primarily come from burning fossil fuels to provide energy for transport , manufacturing, heating , and electricity. Additional CO 2 emissions come from deforestation and industrial processes , which include

12936-671: The last 17,500 acres (7,100 ha) will be permitted for floodplain restoration. Another item to note is that the Design and Construction Enterprise intends to get 2018b permits from the Department of Fish and Wildlife, this permit allows the incidental take of a species listed on the Endangered Species Act. Proposition 1 allocated $ 7.545 billion in general obligation bonds for water projects including surface and groundwater storage, ecosystem and watershed protection and restoration, and drinking water protection. Restoration

13068-436: The last two decades. CO 2 is only removed from the atmosphere for the long term when it is stored in the Earth's crust, which is a process that can take millions of years to complete. Around 30% of Earth's land area is largely unusable for humans ( glaciers , deserts , etc.), 26% is forests , 10% is shrubland and 34% is agricultural land . Deforestation is the main land use change contributor to global warming, as

13200-441: The last: internal climate variability processes can make any year 0.2 °C warmer or colder than the average. From 1998 to 2013, negative phases of two such processes, Pacific Decadal Oscillation (PDO) and Atlantic Multidecadal Oscillation (AMO) caused a short slower period of warming called the " global warming hiatus ". After the "hiatus", the opposite occurred, with years like 2023 exhibiting temperatures well above even

13332-413: The more popular term after NASA climate scientist James Hansen used it in his 1988 testimony in the U.S. Senate . Since the 2000s, climate change has increased usage. Various scientists, politicians and media may use the terms climate crisis or climate emergency to talk about climate change, and may use the term global heating instead of global warming . Over the last few million years

13464-467: The name of "conservation measures" and there were 21 of these measures; the 21 have been cut down to 12 measures and are now known as environmental commitments for the Eco Restore. The environmental commitments are as follows: The proposal in 2019, when it was called the California Water Fix, was a two-tunnel design. Each tunnel would be 150 feet (46 m) below ground, 40 feet (12 m) in diameter and 30 miles (48 km) in length. The tunnel project

13596-481: The need for a gearbox, as well as requires less maintenance and space. The four pumping units are from Cascade Pump Company from Santa Fe Springs, California, Pump Model 48MF with a 48-inch diameter discharge, with the capability to pump 55,125 gallons per minute. Due to the structural deficiencies of the C.W. Bill Jones Pumping Plant , The Intertie improves the overall water delivery system, and allows maintenance and emergencies to be addressed more easily. Completion of

13728-465: The northern portion of the state to Southern California. In the early 1980s, his son, Governor Jerry Brown, attempted a third, the Peripheral Canal, which failed to gain voter support. Governor Arnold Schwarzenegger pushed for the project in 2009 and, when Jerry Brown returned to office as governor in January 2011, he made it one of his two main focuses during his eight years in office. During those years,

13860-604: The project by the California State Auditor. The audit started in April 2017 and took seven months to complete. In September 2017, the audit revealed that $ 50 million of the taxpayers' money was funneled into the project. The size of the WaterFix project is as large or larger than English Channel Tunnel and Boston's Big Dig , both of which were significantly more costly than originally anticipated. The Channel Tunnel project at £4.65 billion (about USD$ 5.10 billion)

13992-438: The project is that a new diversion system and extensive habitat restoration would improve delta conditions, boost the populations of imperiled fish, and ease limits on exports. Those who favor building the tunnels state that pumping water through the tunnels to the pumping plants would mitigate the problem of salt water intrusion into the delta, as the pumps would no longer pump directly from the delta. Proponents also believe that

14124-482: The project morphed from an above-the-ground "peripheral canal" to two huge underground tunnels referred to as the "twin tunnels." The twin tunnel project was finally stopped in 2018 through the work of Delta citizens and support organizations. Governor Gavin Newsom began pushing for a single tunnel project when he took office in 2019. The Central Valley Project (CVP) is a federally owned and operated project completed in

14256-500: The project was April 2012. The cost of construction was an estimated $ 29 million, and will be repaid by the contractors who purchase water. Another key feature is the Tracy Fish Collection Facility. In order to protect threatened and endangered species, a series of sloughs, channels, and tanks, help capture the fish and safely reintroduce them into the Delta waterways. Constructed in the 1950s, its objective

14388-419: The project will only cost each homeowner $ 5 a month, but it hasn't provided any analysis to support the figure. Critics say large projects like this tend to go over budget and the actual cost will be much higher. The state is planning to fund the project using bonds issued by the water agencies, not the state, which if successful would not require approval by the state legislature or a public vote. The study said

14520-415: The project will reduce the amount of freshwater flowing through the delta and cause worsening saltwater intrusion . Farmers in the delta are among the most opposed to the project because it would decrease the amount of water available to them for irrigation. The current federal and state delta water projects that fill the big aqueducts with water for southern California have altered natural water flow, causing

14652-465: The project would protect the state's water system from the sea level rise expected to occur due to global warming . It would also "reinstate a more natural direction of river flows in the South Delta by 46–160 percent". However, opponents note that some of the water that would normally flow into the delta is obligated under senior water rights to farmers in the delta. Opponents are concerned that

14784-699: The project, including national groups such as: the Center for Biological Diversity, National Resources Defense Council, Defenders of Wildlife, Endangered Species Coalition; state groups such as Friends of the River, California SportFishing Protection Alliance, Sierra Club CA, Planning and Conservation League, Restore the Delta , Environmental Protection Information Center, California Water Impact Network, Clean Water Action, Citizens Water Watch Environmental Justice Coalition for Water, Pacific Coast Fed. of Fishermen's Associations, and Golden State Salmon Association ; and regional groups such as The Bay Institute, Coalition to Save

14916-619: The rate at which heat escapes into space, trapping heat near the Earth's surface and warming it over time. While water vapour (≈50%) and clouds (≈25%) are the biggest contributors to the greenhouse effect, they primarily change as a function of temperature and are therefore mostly considered to be feedbacks that change climate sensitivity . On the other hand, concentrations of gases such as CO 2 (≈20%), tropospheric ozone , CFCs and nitrous oxide are added or removed independently from temperature, and are therefore considered to be external forcings that change global temperatures. Before

15048-522: The rate of Arctic shrinkage and underestimated the rate of precipitation increase. Sea level rise since 1990 was underestimated in older models, but more recent models agree well with observations. The 2017 United States-published National Climate Assessment notes that "climate models may still be underestimating or missing relevant feedback processes". Additionally, climate models may be unable to adequately predict short-term regional climatic shifts. A subset of climate models add societal factors to

15180-622: The rate of yield growth . Fisheries have been negatively affected in multiple regions. While agricultural productivity has been positively affected in some high latitude areas, mid- and low-latitude areas have been negatively affected. According to the World Economic Forum, an increase in drought in certain regions could cause 3.2 million deaths from malnutrition by 2050 and stunting in children. With 2 °C warming, global livestock headcounts could decline by 7–10% by 2050, as less animal feed will be available. If

15312-405: The recent average. This is why the temperature change is defined in terms of a 20-year average, which reduces the noise of hot and cold years and decadal climate patterns, and detects the long-term signal. A wide range of other observations reinforce the evidence of warming. The upper atmosphere is cooling, because greenhouse gases are trapping heat near the Earth's surface, and so less heat

15444-495: The region is due to constant over-drafting of underground water. Another key factor is due to the San Joaquin Valley's geomorphological structure, having young continental, unconsolidated sandy-silty-clayish soils, resting on old unconsolidated marine beds. Impacts of the land subsidence lead to a decrease between bridges and water level surface. In regions of greater subsidence, portions of bridges, pipes, and cattle guards would be inundated. Unfortunately, land subsidence has led to

15576-411: The release of chemical compounds that influence clouds, and by changing wind patterns. In tropic and temperate areas the net effect is to produce significant warming, and forest restoration can make local temperatures cooler. At latitudes closer to the poles, there is a cooling effect as forest is replaced by snow-covered (and more reflective) plains. Globally, these increases in surface albedo have been

15708-439: The remaining 10% going to urban users. The CVPIA required that 11% of the water go to environmental uses, with agriculture getting 79% of the water and urban users getting 10%. The State Water Project (SWP) is owned and operated by the state and was conceived and supported in the late 1960s by Governor Edmund Pat Brown . The SWP has 700 miles of canals and can move 5.8 million acre feet of water per year. It uses more than twice

15840-476: The remaining 23%. Some forests have not been fully cleared, but were already degraded by these impacts. Restoring these forests also recovers their potential as a carbon sink. Local vegetation cover impacts how much of the sunlight gets reflected back into space ( albedo ), and how much heat is lost by evaporation . For instance, the change from a dark forest to grassland makes the surface lighter, causing it to reflect more sunlight. Deforestation can also modify

15972-583: The sea levels by at least 3.3 m (10 ft 10 in) over approximately 2000 years. Recent warming has driven many terrestrial and freshwater species poleward and towards higher altitudes . For instance, the range of hundreds of North American birds has shifted northward at an average rate of 1.5 km/year over the past 55 years. Higher atmospheric CO 2 levels and an extended growing season have resulted in global greening. However, heatwaves and drought have reduced ecosystem productivity in some regions. The future balance of these opposing effects

16104-411: The southern 30–40 miles of the canal exceeded subsidence of 6 feet. Nearly two-thirds of the canal has been impacted by subsidence, over 20 miles of the concrete lined canal, and all the earth lined portion. By 1966, 35 miles demonstrated a drop of 1 feet, 3 feet elevation drop in 15 mile stretch, 5 foot decrease in a 5-mile portion, and 2 feet of the canal demonstrated a drop of 6 feet. Land subsidence in

16236-403: The state managed California Aqueduct and the federally managed Delta–Mendota Canal. The pipes have a capacity to pump 467 cubit feet of water per second from the California Aqueduct to the Delta–Mendota Canal. This amount of water restores 35,000 acre feet of water annually to the Central Valley Project . The pumps use vertical power, which are more efficient than horizontal pumps, as it removes

16368-576: The state of California highlighted the importance of a large-scale water project, thus creating the California State Water Plan, but eventually being taken over by the U.S. Bureau of Reclamation in 1931 due to the Great Depression. In 1937 the Central Valley Project was approved by Congress to deliver freshwater throughout the San Joaquin Valley. The Friant-Kern Canal east of Fresno was built to distribute water through

16500-554: The water in the estuary to run backward. They have disturbed the natural salinity patterns The flow of freshwater to the sea is about half of what it once was. To attempt to improve the quality of the bay's fresh water supply, the California State Water Resources Control Board has begun revising the fresh water standards which have not been updated since 1996. In September 2016, the board proposed rules that would allow up to 40 percent of

16632-438: The world. Impacts can be observed on all continents and ocean regions, with low-latitude, less developed areas facing the greatest risk. Continued warming has potentially "severe, pervasive and irreversible impacts" for people and ecosystems. The risks are unevenly distributed, but are generally greater for disadvantaged people in developing and developed countries. The World Health Organization calls climate change one of

16764-490: Was 80% over its predicted budget. The Boston highway project grew from an original estimate of $ 2.8 billion in 1982, and by December 2007 had risen to over $ 14.6 billion, a cost overrun of about 190% when adjusted for inflation. This was before a series of significant defects that resulted in several deaths were discovered. The Boston Globe estimated that the project will ultimately cost $ 22 billion, including interest, and that it would not be paid off until 2038. In August 2016,

16896-505: Was also filed against the project by the Center for Biological Diversity , Sierra Club , and California Sportfishing Protection Alliance. The Metropolitan Water District of Southern California passed a measure to buy four delta islands for $ 175 million earlier in 2016, this buying of delta islands was challenged by many organizations (including San Joaquin, North Coast Rivers Alliance, Pacific Coast Federation of Fishermen's Association), but

17028-803: Was approved by the California Department of Water Resources . The approval was denounced by Congressman Josh Harder , who called it a "disastrous water grab to steal our Valley water." Six agencies are responsible for funding the project. The Santa Clara Valley Water District receives 40% of its water from both the SWP and CVP and serves 1.9 million residents of Silicon Valley. The San Joaquin River Exchange Contractors Water Authority serves 240,000 acres (97,000 ha) and received 50% of its water from CVP in 2015. The San Luis & Delta-Mendota Water Authority

17160-647: Was funded by the Delta Counties Coalition, representing Contra Costa, Sacramento, San Joaquin, Solano, and Yolo county governments. The application of the Eco Restore is not guaranteed because of a bill that has been introduced in the House and has currently been assigned to the House Appropriations committee. Bill H.R. 5055 makes it so there is a no funding for restoration along the San Joaquin River and it would make it so that pumping

17292-524: Was sending more energy to Earth, but instead, it has been cooling. This is consistent with greenhouse gases preventing heat from leaving the Earth's atmosphere. Explosive volcanic eruptions can release gases, dust and ash that partially block sunlight and reduce temperatures, or they can send water vapour into the atmosphere, which adds to greenhouse gases and increases temperatures. These impacts on temperature only last for several years, because both water vapour and volcanic material have low persistence in

17424-482: Was submitted to the voters for approval as a ballot referendum in 1982 but was turned down. The WaterFix and EcoRestore project was previously called the Bay Delta Conservation Plan. When proposed in 2009, the project as originally conceived included both plans for building the tunnels and restoring the delta. The Bay Delta Conservation Plan included restoring 100,000 acres (40,000 ha) over

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