South Coast

Climatic Fluctuations, Drought, and Flow in the Colorado River Basin

U.S. Geological Survey (USGS) | August 16th, 2004

Coastal hardening and what it means for the world’s sandy beaches

Publisher not available | December 5th, 2024

Coastal Plain of Orange County, Basin 8-001 Alternative to a Groundwater Sustainability Plan

Orange County Water District (OCWD) | January 1st, 2017

Coastal vulnerability across the Pacific dominated by El Niño/Southern Oscillation

Nature Portfolio (Springer Nature) | September 21st, 2015

To predict future coastal hazards, it is important to quantify any links between climate drivers and spatial patterns of coastal change. However, most studies of future c

To predict future coastal hazards, it is important to quantify any links between climate drivers and spatial patterns of coastal change. However, most studies of future coastal vulnerability do not account for the dynamic components of coastal water levels during storms, notably wave-driven processes, storm surges and seasonal water level anomalies, although these components can add metres to water levels during extreme events. Here we synthesize multi-decadal, co-located data assimilated between 1979 and 2012 that describe wave climate, local water levels and coastal change for 48 beaches throughout the Pacific Ocean basin. We find that observed coastal erosion across the Pacific varies most closely with El Niño/Southern Oscillation, with a smaller influence from the Southern Annular Mode and the Pacific North American pattern. In the northern and southern Pacific Ocean, regional wave and water level anomalies are significantly correlated to a suite of climate indices, particularly during boreal winter; conditions in the northeast Pacific Ocean are often opposite to those in the western and southern Pacific. We conclude that, if projections for an increasing frequency of extreme El Niño and La Niña events over the twenty-first century are confirmed, then populated regions on opposite sides of the Pacific Ocean basin could be alternately exposed to extreme coastal erosion and flooding, independent of sea-level rise.

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

Commercial, Industrial, and Institutional Task Force Water Use Best Management Practices Report to the Legislature

California Department of Water Resources (DWR) | October 21st, 2013

This report to Legislature, Commercial, Industrial, and Institutional Task Force Water Use Best Management Practices, identifies specific practices to improve water use e

This report to Legislature, Commercial, Industrial, and Institutional Task Force Water Use Best Management Practices, identifies specific practices to improve water use efficiency and support California’s water supply sustainability. It is intended to provide the CII sectors with information on water-saving technologies and BMPs applicable in the CII sectors. The report is also intended for use as a resource for: • Existing and new businesses, facilities, and institutions • Developers, consultants, and designers • Water service providers • Planning agencies • Policy makers This two-part document is linked below.  The Executive Summary is also linked in the display window. Executive Summary Volume 1 - A Summary Volume 2 - Technical Information

Community estimate of global glacier mass changes from 2000 to 2023

Nature Portfolio (Springer Nature) | February 19th, 2025

Glaciers are indicators of ongoing anthropogenic climate change1. Their melting leads to increased local geohazards2, and impacts marine3 and terrestrial4,5 ecosystems, r

Glaciers are indicators of ongoing anthropogenic climate change1. Their melting leads to increased local geohazards2, and impacts marine3 and terrestrial4,5 ecosystems, regional freshwater resources6, and both global water and energy cycles7,8. Together with the Greenland and Antarctic ice sheets, glaciers are essential drivers of present9,10 and future11,12,13 sea-level rise. Previous assessments of global glacier mass changes have been hampered by spatial and temporal limitations and the heterogeneity of existing data series14,15,16. Here we show in an intercomparison exercise that glaciers worldwide lost 273 ± 16 gigatonnes in mass annually from 2000 to 2023, with an increase of 36 ± 10% from the first (2000–2011) to the second (2012–2023) half of the period. Since 2000, glaciers have lost between 2% and 39% of their ice regionally and about 5% globally. Glacier mass loss is about 18% larger than the loss from the Greenland Ice Sheet and more than twice that from the Antarctic Ice Sheet17. Our results arise from a scientific community effort to collect, homogenize, combine and analyse glacier mass changes from in situ and remote-sensing observations. Although our estimates are in agreement with findings from previous assessments14,15,16 at a global scale, we found some large regional deviations owing to systematic differences among observation methods. Our results provide a refined baseline for better understanding observational differences and for calibrating model ensembles12,16,18, which will help to narrow projection uncertainty for the twenty-first century11,12,18. Click here for more about the Glacier Mass Balance Intercomparison Exercise 

Community Exposure to Tsunami Hazards in California

U.S. Geological Survey (USGS) | February 20th, 2013

Evidence of past events and modeling of potential events suggest that tsunamis are significant threats to low-lying communities on the California coast. To reduce potenti

Evidence of past events and modeling of potential events suggest that tsunamis are significant threats to low-lying communities on the California coast. To reduce potential impacts of future tsunamis, officials need to understand how communities are vulnerable to tsunamis and where targeted outreach, preparedness, and mitigation efforts may be warranted. Although a maximum tsunami-inundation zone based on multiple sources has been developed for the California coast, the populations and businesses in this zone have not been documented in a comprehensive way. To support tsunami preparedness and risk-reduction planning in California, this study documents the variations among coastal communities in the amounts, types, and percentages of developed land, human populations, and businesses in the maximum tsunami-inundation zone.  The tsunami-inundation zone includes land in 94 incorporated cities, 83 unincorporated communities, and 20 counties on the California coast. According to 2010 U.S. Census Bureau data, this tsunami-inundation zone contains 267,347 residents (1 percent of the 20-county resident population), of which 13 percent identify themselves as Hispanic or Latino, 14 percent identify themselves as Asian, 16 percent are more than 65 years in age, 12 percent live in unincorporated areas, and 51 percent of the households are renter occupied. Demographic attributes related to age, race, ethnicity, and household status of residents in tsunami-prone areas demonstrate substantial range among communities that exceed these regional averages. The tsunami-inundation zone in several communities also has high numbers of residents in institutionalized and noninstitutionalized group quarters (for example, correctional facilities and military housing, respectively). Communities with relatively high values in the various demographic categories are identified throughout the report. The tsunami-inundation zone contains significant nonresidential populations based on 2011 economic data from Infogroup (2011), including 168,565 employees (2 percent of the 20-county labor force) at 15,335 businesses that generate approximately $30 billion in annual sales. Although the regional percentage of at-risk employees is low, certain communities, such as Belvedere, Alameda, and Crescent City, have high percentages of their local workforce in the tsunami-inundation zone. Employees in the tsunami-inundation zone are primarily in businesses associated with tourism (for example, accommodations, food services, and retail trade) and shipping (for example, transportation and warehousing, manufacturing, and wholesale trade), although the dominance of these sectors varies substantially among the 94 cities.  Although the number of occupants is not known for each site, the tsunami-inundation zone contains numerous dependent-population facilities, such as schools and child daycare centers, which may have individuals with limited mobility. The tsunami-inundation zone includes a substantial number of facilities that provide community services, such as banks, religious organizations, and grocery stores, where local residents may be unaware of evacuation procedures if previous awareness efforts focused on home preparedness. There are also numerous recreational areas in the tsunami-inundation zone, such as amusement parks, marinas, city and county beaches, and State and national parks, which attract visitors who may not be aware of tsunami hazards or evacuation procedures. During peak summer months, estimated daily attendance at city and county beaches can be approximately six times larger than the total number of residents in the tsunami-inundation zone.  Community exposure to tsunamis in California varies considerably—some communities may experience great losses that reflect only a small part of their community and others may experience relatively small losses that devastate them. Among 94 incorporated communities and the remaining unincorporated areas of the 20 coastal counties, the communities of Alameda, Oakland, Long Beach, Los Angeles, Huntington Beach, and San Diego have the highest number of people and businesses in the tsunami-inundation zone. The communities of Belvedere, Alameda, Crescent City, Emeryville, Seal Beach, and Sausalito have the highest percentages of people and businesses in this zone. On the basis of a composite index, the cities of Alameda, Belvedere, Crescent City, Emeryville, Oakland, and Long Beach have the highest combinations of the number and percentage of people and businesses in tsunami-prone areas.

Comparison of potential drinking water source contamination across one hundred U.S. cities

Nature Portfolio (Springer Nature) | December 13th, 2021

Drinking water supplies of cities are exposed to potential contamination arising from land use and other anthropogenic activities in local and distal source watersheds. B

Drinking water supplies of cities are exposed to potential contamination arising from land use and other anthropogenic activities in local and distal source watersheds. Because water quality sampling surveys are often piecemeal, regionally inconsistent, and incomplete with respect to unregulated contaminants, the United States lacks a detailed comparison of potential source water contamination across all of its large cities. Here we combine national scale geospatial datasets with hydrologic simulations to compute two metrics representing potential contamination of water supplies from point and nonpoint sources for over a hundred U.S. cities. We reveal enormous diversity in anthropogenic activities across watersheds with corresponding disparities in the potential contamination of drinking water supplies to cities. Approximately 5% of large cities rely on water that is composed primarily of runoff from non-pristine lands (e.g., agriculture, residential, industrial), while four-fifths of all large cities that withdraw surface water are exposed to treated wastewater in their supplies.