California Aqueduct

File:Banks of San Luis Reservoir in July 2021 redux.JPG

The aqueduct serves 35 million people and 5.7 million acres of farmland,{{cite magazine |last1=Simon |first1=Matt |title=Why Covering Canals With Solar Panels Is a Power Move |url=https://www.wired.com/story/why-covering-canals-with-solar-panels-is-a-power-move/ |magazine=Wired |archive-url= https://web.archive.org/web/20210504114119/https://www.wired.com/story/why-covering-canals-with-solar-panels-is-a-power-move/ |archive-date=4 May 2021 |date=19 March 2021 |url-status=live}} and begins at the San Joaquin-Sacramento River Delta at the Banks Pumping Plant, which pumps from the Clifton Court Forebay. Water is pumped by the Banks Pumping Plant to the Bethany Reservoir. The reservoir serves as a forebay for the South Bay Aqueduct via the South Bay Pumping Plant. From the Bethany Reservoir, the aqueduct flows by gravity approximately {{convert|60|mi|abbr=on}} to the O'Neill Forebay at the San Luis Reservoir. From the O'Neill Forebay, it flows approximately {{convert|16|mi|abbr=on}} to the Dos Amigos Pumping Plant. After Dos Amigos, the aqueduct flows about {{convert|95|mi|abbr=on}} to where the Coastal Branch splits from the "main line". The split is approximately {{convert|16|mi|abbr=on}} south-southeast of Kettleman City. After the coastal branch, the line continues by gravity another {{convert|66|mi|abbr=on}} to the Buena Vista Pumping Plant. From the Buena Vista, it flows approximately {{convert|27|mi|abbr=on}} to the Teerink Pumping Plant. After Teerink it flows about {{convert|2.5|mi|abbr=on}} to the Chrisman Pumping Plant. Chrisman is the last pumping plant before Edmonston Pumping Plant, which is {{convert|13|mi|abbr=on}} from Chrisman. South of the plant the west branch splits off in a southwesterly direction to serve the Los Angeles Basin. At Edmonston Pumping Plant it is pumped {{convert|1926|ft|abbr=on}} over the Tehachapi Mountains.{{cite web | title=Edmonston Pumping Plant | url=http://ludb.clui.org/ex/i/CA4967/ | publisher=Center for Land Use Interpretation | year=2009 | access-date=2009-03-19 | archive-url=https://web.archive.org/web/20080724201036/http://ludb.clui.org/ex/i/CA4967/ | archive-date=2008-07-24 | url-status=dead }}

Water flows through the aqueduct in a series of abrupt rises and gradual falls. The water flows down a long segment, built at a slight grade, and arrives at a pumping station powered by Path 66 or Path 15. The pumping station raises the water, where it again gradually flows downhill to the next station. However, where there are substantial drops, the water's potential energy is recaptured by hydroelectric plants. The initial pumping station fed by the Sacramento River Delta raises the water {{convert|240|ft|abbr=on}}, while a series of pumps culminating at the Edmonston Pumping Plant raises the water {{convert|1926|ft|abbr=on}} over the Tehachapi Mountains.

A typical section has a concrete-lined channel {{convert|40|ft}} at the base and an average water depth of about {{convert|30|ft|abbr=on}}. The widest section of the aqueduct is {{convert|110|ft}} and the deepest is {{convert|32|ft}}. Channel capacity is {{convert|13100|ft3/s}} and the largest pumping plant capacity at Dos Amigos is {{convert|15450|ft3/s}}.

A 2021 study published in Nature Sustainability estimated that the installation of solar panels over the canal could potentially reduce annual water evaporation by {{convert|27000000|-|51000000|L/km|e6USgal/mi|order=flip}} of canal. While electricity generated by the solar panels could be used by the aqueduct's pumping systems, the study also considered the possibility of supplying power to irrigation systems in the Central Valley to reduce reliance on diesel-powered irrigation pumps. Similar canal-spanning solar installations have been demonstrated in India, including a steel truss design in Gujarat and a suspension cable design in Punjab.{{cite journal |last1=McKuin |first1=Brandi |last2=Zumkehr |first2=Andrew |last3=Ta |first3=Jenny |last4=Bales |first4=Roger |last5=Viers |first5=Joshua H. |last6=Pathak |first6=Tapan |last7=Campbell |first7=J. Elliott |title=Energy and water co-benefits from covering canals with solar panels |journal=Nature Sustainability |date=2021-03-18 |volume=4 |issue=7 |pages=609–617 |doi=10.1038/s41893-021-00693-8|s2cid=232273487 |url=https://escholarship.org/uc/item/8cj5j07p }}

From its beginning until its first branch, the aqueduct passes through parts of Contra Costa, Alameda, San Joaquin, Stanislaus, Merced, Fresno, and Kings counties. The aqueduct then divides into three branches: the Coastal Branch in the Central Valley, and the East and West Branches after passing over the Tehachapi Mountains.

File:Kern-County-farms-and-california-aqueduct-Aerial-from-west-August-2014.jpg]]

The Coastal Branch splits from the main line {{convert|11.3|mi|abbr=on}} south-southeast of Kettleman City transiting Kings County, Kern County, San Luis Obispo County, and Santa Barbara County to deliver water to the coastal cities of San Luis Obispo, Santa Maria, and Santa Barbara.{{cite book | last=Carle | first=David | title=Introduction to Water in California | pages=[https://archive.org/details/isbn_9780520240865/page/97 97]–99 | location=Berkeley | publisher=University of California Press | url=https://archive.org/details/isbn_9780520240865| url-access=registration | year=2004 | isbn=0-520-23580-0 }} The Coastal Branch is {{convert|116|mi|abbr=on}} and has five pump stations. Phase I, an above-ground aqueduct totaling {{convert|15|mi|abbr=on}} from where it branches from the California Aqueduct, was completed in 1968. With construction beginning in 1994, Phase II consists of {{convert|101|mi|abbr=on}} of a {{convert|42|-|57|in|m|2|adj=on}} diameter buried pipeline extending from the Devils Den Pump Plant, and terminates at Tank 5 on Vandenberg Space Force Base in Santa Barbara County. The Central Coast Water Authority (CCWA) extension, completed in 1997, is a (30–39 in) (76–99 cm) diameter pipeline that travels {{convert|42|mi|abbr=on}} from Vandenberg through Vandenberg Village, Lompoc, Buellton, and Solvang where it terminates at Lake Cachuma in Los Padres National Forest.{{cite web | title=State Water Project in Santa Barbara County | url=http://www.ccwa.com/history/index.html | publisher=Central Coast Water Authority | date=10 March 2003 | access-date=2009-03-22 | url-status=dead | archive-url=https://web.archive.org/web/20091211160718/http://www.ccwa.com/history/index.html | archive-date=11 December 2009 }}

Coastal Branch facilities include:{{Cite web|url=https://water.ca.gov/Programs/State-Water-Project/SWP-Facilities|title=Facilities|date=April 7, 2019|website=California Department of Water Resources}}

• Las Perillas Pumping Plant
• Badger Hill Pumping Plant
• Devil's Den Pumping Plant
• Bluestone Pumping Plant
• Polonio Pass Pumping Plant
• Polonio Pass Water Treatment Plant
• Cuesta Tunnel{{Cite web|url=https://water.ca.gov/LegacyFiles/recreation/brochures/pdf/Coastal_Branch_Brochure.pdf|title=Coastal Branch Brochure|website=California Department of Water Resources}}
• Santa Ynez Pumping Facility

File:California Aqueduct east of route 138.jpg

The aqueduct splits off into the East Branch and West Branch in extreme southern Kern County, north of the Los Angeles County line. The East Branch supplies Lake Palmdale and terminates at Lake Perris, in the area of the San Gorgonio Pass. It passes through parts of Kern, Los Angeles, San Bernardino, and Riverside counties.

East Branch facilities include:

• Tehachapi East Afterbay
• Alamo Power Plant
• Pearblossom Pumping Plant
• Mojave Siphon
• Mojave Siphon Power Plant
• Cedar Springs Dam
• Silverwood Lake
• San Bernardino Intake Structure
• San Bernardino Tunnel
• Devil Canyon Power Plant
• Devil Canyon Afterbay 1 and Afterbay 2
• Greenspot Pump Station (Backup)
• Citrus Reservoir
• Citrus Pump Station
• Crafton Hills Reservoir
• Crafton Hills Pump Station
• Cherry Valley Pump Station
• Perris Lake and Dam

The West Branch continues to head towards its terminus at Pyramid Lake and Castaic Lake in the Angeles National Forest to supply the western Los Angeles basin. It passes through parts of Kern and Los Angeles counties.

West Branch facilities include

• Oso Pumping Plant
• Peace Valley Pipeline
• Warne Powerplant
• Angeles Tunnel
• Castaic Power Plant

When it was open, the California Aqueduct Bikeway was the longest of the paved paths in the Los Angeles area, at {{convert|107|mi|km}} long from Quail Lake near Gorman in the Sierra Pelona Mountains through the desert to Silverwood Lake in the San Bernardino Mountains. This path was closed in 1988 due to bicyclist safety and liability issues. It is expected to remain closed indefinitely due to the continued liability issues and an increased focus on security, especially after the September 11, 2001 attacks.

{{wide image | California Aqueduct fishing spot near Pearblossom.jpg | 800 px | Fishing spot and closed bikeway near Pearblossom, panoramic view}}

; Phase I, canal

• Las Perillas Pumping Plant {{coord|35.843143|-119.909055|format=dms}}, Kings County
• Badger Hill Pumping Plant {{coord|35.834680|-119.942658|format=dms}}, Kings County

; Phase II, pipeline and tunnel

• Devil's Den Pumping Plant {{coord|35.711935|-120.010958|format=dms}}, Kern County
• Bluestone Pumping Plant {{coord|35.707946|-120.084429|format=dms}}, Kern County
• Polonio Pass Pumping Plant {{coord|35.731046|-120.207682|format=dms}}, San Luis Obispo County

{{multiple image

| align = top

| direction = vertical

| footer = San Joaquin River watershed and Tulare Basin

| image1 = Sacramento River basin map.png

| width1 = 220

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| caption1 = Sacramento River watershed

| image2 = San Joaquin River watershed.png

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}}

Two major river systems drain and define the two parts of the Central Valley. Their impact on the California Aqueduct is both direct and indirect. The Sacramento River, along with its tributaries the Feather River and American River, flows southwards through the Sacramento Valley for about {{convert|447|mi|km}}.{{cite web

| url = http://ca.water.usgs.gov/sac_nawqa/study_description.html

| title = Sacramento River Basin National Water Quality Assessment Program: Study Unit Description

| publisher = ca.water.usgs.gov

| work = United States Geological Survey

| access-date = 2009-07-26}} In the San Joaquin Valley, the San Joaquin River flows roughly northwest for {{convert|365|mi|km}}, picking up tributaries such as the Merced River, Tuolumne River, Stanislaus River and Mokelumne River.{{cite web

| url = http://www.nrdc.org/water/conservation/sanjoaquin.asp

| title = Restoring the San Joaquin River: Following an 18-year legal battle, a great California river once given up for dead is on the verge of a comeback

| publisher = www.nrdc.org

| work = Natural Resources Defense Council

| date = 17 September 2007

| access-date = 2009-07-26}}

In the south part of the San Joaquin Valley, the alluvial fan of the Kings River and another one from Coast Ranges streams have created a divide and resultantly the currently dry Tulare basin of the Central Valley, into which flow four major Sierra Nevada rivers, the Kings, Kaweah, Tule and Kern. This basin, usually endorheic, formerly filled during heavy snowmelt and spilled out into the San Joaquin River. Called Tulare Lake, it is usually dry nowadays because the rivers feeding it have been diverted for agricultural purposes.{{cite web

| url = http://www.tularehistoricalmuseum.org/Articles/tularelake.htm

| archive-url = https://web.archive.org/web/20100219075308/http://www.tularehistoricalmuseum.org/Articles/tularelake.htm

| archive-date = 2010-02-19

| title = Tulare Lake

| publisher = www.tularehistoricalmueseum.org

| work = Tulare Historical Museum

| last = Gorelick

| first = Ellen

| access-date = 2009-07-26}}

The rivers of the Central Valley converge in the Sacramento-San Joaquin Delta, a complex network of marshy channels, distributaries and sloughs that wind around islands mainly used for agriculture. Here the freshwater of the rivers merges with tidewater, and eventually reach the Pacific Ocean after passing through Suisun Bay, San Pablo Bay, upper San Francisco Bay and finally the Golden Gate. Many of the islands now lie below sea level because of intensive agriculture, and have a high risk of flooding, which would cause salt water to rush back into the delta, especially when there is too little fresh water flowing in from the Valley.{{cite web

| url = http://pubs.usgs.gov/fs/2000/fs00500/pdf/fs00500.pdf

| title = Delta Subsidence in California: The sinking heart of the State

| work = United States Geological Survey

| publisher = ca.water.usgs.gov

| access-date = 2009-07-26}}

The Sacramento River carries far more water than the San Joaquin, with an estimated {{convert|22|e6acre.ft|km3}} of virgin annual runoff, as compared to the San Joaquin's approximately {{convert|6|e6acre.ft|km3}}. Intensive agricultural and municipal water consumption has reduced the present rate of outflow to about {{convert|17|e6acre.ft|km3}} for the Sacramento and {{convert|3|e6acre.ft|km3}} for the San Joaquin; however, these figures still vary widely from year to year. Over 25 million people, living both in the valley and in other regions of the state, rely on the water carried by these rivers.{{cite web

| url = http://www.americanrivers.org/our-work/protecting-rivers/endangered-rivers/sac-san-joaquin.html

| title = Sacramento-San Joaquin River System, California

| publisher = America's Most Endangered Rivers Report: 2009 Edition

| work = American Rivers

| access-date = 2009-07-26

| url-status = dead

| archive-url = https://web.archive.org/web/20100117045520/http://www.americanrivers.org/our-work/protecting-rivers/endangered-rivers/sac-san-joaquin.html

| archive-date = 2010-01-17

}}

Land subsidence is when the land gradually or suddenly sinks or settles due to movement or removal of natural materials such as water, minerals, oil and natural gases.{{Cite web |last=US Department of Commerce |first=National Oceanic and Atmospheric Administration |title=What is subsidence? |url=https://oceanservice.noaa.gov/facts/subsidence.html |access-date=2022-04-01 |website=oceanservice.noaa.gov |language=EN-US}} More often than not, subsidence occurs when large quantities of groundwater are removed from sediment or rocks.{{Cite web |title=CMUA |url=https://www.cmua.org/2021-issue-brief-subsidence |access-date=2022-04-01 |website=www.cmua.org}} As groundwater is drawn from deep underground layers of clay, the clay compresses, causing subsidence.{{Cite web |last=Stokstad |first=Erik |date=April 16, 2020 |title=Droughts highlighted California's unsustainable use of groundwater. Now, the state is trying to refill its aquifers. |url=https://www.science.org/content/article/droughts-exposed-california-s-thirst-groundwater-now-state-hopes-refill-its-aquifers |access-date=October 3, 2023 |website=Science}} In cases of groundwater removal, disruption to land on the surface and underground water storage can either be elastic, meaning recoverable, or inelastic, meaning permanent.{{Cite journal |last1=Miller |first1=Megan M. |last2=Jones |first2=Cathleen E. |last3=Sangha |first3=Simran S. |last4=Bekaert |first4=David P. |date=2020-12-15 |title=Rapid drought-induced land subsidence and its impact on the California aqueduct |url=https://www.sciencedirect.com/science/article/pii/S0034425720304338 |journal=Remote Sensing of Environment |volume=251 |pages=112063 |doi=10.1016/j.rse.2020.112063 |s2cid=225017671 |issn=0034-4257}} Coarse-grained sediment which holds groundwater can be drained and recharged with minimal underground and surface level damage and the change that does occur is considered seasonal subsidence. However, fine-grained sediment takes longer to draw water out of and recharge and if groundwater levels are left low for too long, the compaction of the sediment is permanent and causes irreversible land subsidence. This often occurs due to human interference, but can also happen from natural phenomena. Subsidence can happen over very large areas or small little sections of land. This has occurred along the California Aqueduct of the State Water Project since construction.

Human causes include; pumping, mining and fracking.

Natural causes include; earthquakes, erosion, glacial movement, soil compaction and the formation of sinkholes.

Groundwater use and pumping in the area was the major water use for farmers and agriculture in the 1920s, and over time, this over-pumping resulted in land subsidence and a decline in groundwater-level resources. In time, this resulted in major land subsidence by the 1970s with local areas having {{cvt|1|to|28|feet|meter|order=flip|sigfig=2}} of subsidence. With the creation and use of the California Aqueduct along these regions, surface water being transported put a halt on significant compaction and a recovery in ground water levels now with less ground water pumping.{{Cite web |title=California Aqueduct Subsidence {{!}} USGS California Water Science Center |url=https://ca.water.usgs.gov/projects/central-valley/california-aqueduct-subsidence.html |access-date=2022-04-01 |website=ca.water.usgs.gov}} The aqueduct has been increasing in subsidence rates rapidly, even though it was relatively stable for many years after being constructed.{{Cite web |title=California Aqueduct Subsidence Program |url=https://water.ca.gov/Programs/Engineering-And-Construction/Subsidence |access-date=2022-05-02 |website=water.ca.gov |language=en}} The Tulare Basin is subsiding at a rate of about 30 cm (one foot) per year, as measured by NASA's GRACE satellite.{{Cite web |last=Hartono |first=Naomi |date=2022-04-05 |title=NASA Finds New Way to Monitor Underground Water Loss |url=http://www.nasa.gov/feature/jpl/nasa-finds-new-way-to-monitor-underground-water-loss |access-date=2022-05-04 |website=NASA}} The Central Valley, where a large portion of the California Aqueduct runs through, has been affected by the pumping of groundwater and subsequent land subsidence.{{Cite journal |last1=Jeanne |first1=Pierre |last2=Farr |first2=Tom G. |last3=Rutqvist |first3=Jonny |last4=Vasco |first4=Donald W. |date=2019-02-01 |title=Role of agricultural activity on land subsidence in the San Joaquin Valley, California |url=https://www.sciencedirect.com/science/article/pii/S0022169418309661 |journal=Journal of Hydrology |volume=569 |pages=462–469 |doi=10.1016/j.jhydrol.2018.11.077 |s2cid=135110152 |issn=0022-1694}} Farmers in and near the Central Valley have become reliant on groundwater especially with recent droughts impacting the amount of readily accessible surface water. However, overuse of groundwater can cause irreversible damage. During the 2011-2017 California drought, a record high drought, groundwater and its storage capabilities in the San Joaquin Valley saw a sharp decline.{{Cite journal |last1=Ojha |first1=Chandrakanta |last2=Werth |first2=Susanna |last3=Shirzaei |first3=Manoochehr |date=March 2019 |title=Groundwater Loss and Aquifer System Compaction in San Joaquin Valley During 2012–2015 Drought |journal=Journal of Geophysical Research: Solid Earth |language=en |volume=124 |issue=3 |pages=3127–3143 |doi=10.1029/2018JB016083 |issn=2169-9313 |pmc=6559157 |pmid=31218156}} From October 2011 to September 2015 measurements made on groundwater levels in the San Joaquin Valley's aquifers recorded a loss of 14 km³/year, a total of 56 km³. During this same period up to 1,000 mm of land subsidence was measured in the San Joaquin Valley. Concerns around groundwater depletion have contributed to legislation to reduce the demand for groundwater and incentivize farmers to use sustainable irrigation practices.

Measurement of this subsidence is done in a few ways. Originally, subsidence was recorded based on land surveying, repeating the surveying, and along with monitoring compaction by recording the data from extensometers at multiple sites. Since then, Global Positioning Systems (GPS) has been used along with land surveying to record subsidence and compaction. More recently, interferometric synthetic aperture radar (InSAR) has been used to monitor subsidence along with GPS. InSAR is being used to recreate maps to closely watch the progression of the land around the aqueduct.{{Cite web |last=Greicius |first=Tony |date=2017-02-28 |title=NASA Data Show California's San Joaquin Valley Still Sinking |url=http://www.nasa.gov/feature/jpl/nasa-data-show-californias-san-joaquin-valley-still-sinking |access-date=2022-04-01 |website=NASA}}

Subsidence can put land, both private and public, at risk of infrastructure damage. Bridges, levees, roads, and groundwater wells are either at risk of damage or have been damaged already. With subsidence progression, underground aquifers could be at risk and water storage from them could be threatened. Damage and sinking of the canal of the aqueduct has already occurred from subsidence which has made the canal less reliable. Capacity has been compromised due to damage to the canals and therefore has caused problems and delays with delivering the water across the state, as well as higher rates and costs for power and operation.

A documentary about the decline of the United States' infrastructure, The Crumbling of America,{{cite web | url=https://www.youtube.com/watch?v=zBSPcIGGcIc | title=The Crumbling of America (2:49 introductory clip) | website=YouTube | access-date=2013-09-11}} was commissioned by the U.S. A&E network in the late 2000s. The documentary is typically shown on the History television channel in the United States, although other educational broadcasters globally have shown it. It features the Clifton Court Forebay (a primary intake point for California Aqueduct) as a "strategic piece of California freshwater infrastructure" subject to shutdown for up to two years if struck by an earthquake of magnitude 7.5 or greater.

The aqueduct is featured in an episode of California's Gold with Huell Howser.{{cite web |title=California Aqueduct Special – California's Gold (001) – Huell Howser Archives at Chapman University |date=May 3, 2016 |url=https://blogs.chapman.edu/huell-howser-archives/2016/05/03/california-aqueduct-special-californias-gold-001/}}

• Colorado River Aqueduct
• Los Angeles Aqueduct

{{Reflist}}

{{commons category|California Aqueduct|
California Aqueduct}}

• [http://www.water.ca.gov/ The California Department of Water Resources website]
• [https://web.archive.org/web/20140708205516/http://www.wecc.biz/committees/BOD/TEPPC/Lists/Calendar/Attachments/244/130807_WECC_Pumped_Storage_Analysis_PPT_HMTF.pdf Historic Pump-Storage Operation in WSCC]
• USGS Geographic Names Information System data
• {{GNIS 2|270163|Governor Edmund G Brown California Aqueduct}}
• {{GNIS 2|2729385|Governor Edmund G Brown Coastal Branch California Aqueduct}}
• {{GNIS 2|2729392|Governor Edmund G Brown East Branch California Aqueduct}}
• {{GNIS 2|274419|Governor Edmund G Brown West Branch California Aqueduct}}

{{State Water Project}}

Category:Aqueducts in California

Category:California State Water Project

Category:Interbasin transfer

Category:Central Valley (California)

Category:Southern California

Category:Transportation buildings and structures in California

Category:Water in California