The Enduring Role of Tribes in the Colorado River Basin

Water and Tribes Initiative | July 1st, 2019

The purpose of this policy brief is to explain the origin, rationale, and purpose of the Water & Tribes Initiative in the Colorado River Basin. As explained more fully be

The purpose of this policy brief is to explain the origin, rationale, and purpose of the Water & Tribes Initiative in the Colorado River Basin. As explained more fully below, the long-term objectives of this Initiative are to: • Enhance the capacity of tribes to advance their needs and interests with respect to water management in the basin; and • Advance sustainable water management through collaborative decision-making.

The Essential Role of Local Context in Shaping Risk and Risk Reduction Strategies for Snowmelt-Dependent Irrigated Agriculture

American Geophysical Union (AGU) | June 11th, 2024

The estimated impact of California’s urban water conservation mandate on electricity consumption and greenhouse gas emissions

Environmental Research Letters (IOP) | January 12th, 2018

In April 2015, the Governor of California mandated a 25% statewide reduction in water consumption (relative to 2013 levels) by urban water suppliers. The more tha

In April 2015, the Governor of California mandated a 25% statewide reduction in water consumption (relative to 2013 levels) by urban water suppliers. The more than 400 public water agencies affected by the regulation were also required to report monthly progress towards the conservation goal to the State Water Resources Control Board. This paper uses the reported data to assess how the water utilities have responded to this mandate and to estimate the electricity savings and greenhouse gas (GHG) emissions reductions associated with reduced operation of urban water infrastructure systems. The results show that California succeeded in saving 524,000 million gallons (MG) of water (a 24.5% decrease relative to the 2013 baseline) over the mandate period, which translates into 1830 GWh total electricity savings, and a GHG emissions reduction of 521,000 metric tonnes of carbon dioxide equivalents (MT CO2e). For comparison, the total electricity savings linked to water conservation are approximately 11% greater than the savings achieved by the investor-owned electricity utilities’ efficiency programs for roughly the same time period, and the GHG savings represent the equivalent of taking about 111 000 cars off the road for a year. These indirect, large-scale electricity and GHG savings were achieved at costs that were competitive with existing programs that target electricity and GHG savings directly and independently. Finally, given the breadth of the results produced, we built a companion website, called H2Open, to this research effort that allows users to view and explore the data and results across scales, from individual water utilities to the statewide summary.

The Evaporative Demand Drought Index. Part I: Linking Drought Evolution to Variations in Evaporative Demand

American Meteorological Society (AMS) | March 1st, 2016

Many operational drought indices focus primarily on precipitation and temperature when depicting hydroclimatic anomalies, and this perspective can be augmented by analys

Many operational drought indices focus primarily on precipitation and temperature when depicting hydroclimatic anomalies, and this perspective can be augmented by analyses and products that reflect the evaporative dynamics of drought. The linkage between atmospheric evaporative demand E0 and actual evapotranspiration (ET) is leveraged in a new drought index based solely on E0—the Evaporative Demand Drought Index (EDDI). EDDI measures the signal of drought through the response of E0 to surface drying anomalies that result from two distinct land surface–atmosphere interactions: 1) a complementary relationship between E0 and ET that develops under moisture limitations at the land surface, leading to ET declining and increasing E0, as in sustained droughts, and 2) parallel ET and E0 increases arising from increased energy availability that lead to surface moisture limitations, as in flash droughts. To calculate EDDI from E0, a longterm, daily reanalysis of reference ET estimated from the American Society of Civil Engineers (ASCE) standardized reference ET equation using radiation and meteorological variables from the North American Land Data Assimilation System phase 2 (NLDAS-2) is used. EDDI is obtained by deriving empirical probabilities of aggregated E0 depths relative to their climatologic means across a user-specific time period and normalizing these probabilities. Positive EDDI values then indicate drier-than-normal conditions and the potential for drought. EDDI is a physically based, multiscalar drought index that that can serve as an indicator of both flash and sustained droughts, in some hydroclimates offering early warning relative to current operational drought indices. The performance of EDDI is assessed against other commonly used drought metrics across CONUS in Part II.

The evolution of dam induced river fragmentation in the United States

Nature Portfolio (Springer Nature) | June 28th, 2023

The evolution of human population distance to water in the USA from 1790 to 2010

Nature Portfolio (Springer Nature) | January 25th, 2019

Human societies evolved alongside rivers, but how has the relationship between human settlement locations and water resources evolved over time? We conducted a dynamic 

Human societies evolved alongside rivers, but how has the relationship between human settlement locations and water resources evolved over time? We conducted a dynamic analysis in the conterminous US to assess the coevolution of humans and water resources from 1790 to 2010. Here we show that humans moved closer to major rivers in pre-industrial periods but have moved farther from major rivers after 1870, demonstrating the dynamics of human reliance on rivers for trade and transport. We show that humans were preferentially attracted to areas overlying major aquifers since industrialization due to the emergent accessibility of groundwater in the 20th century. Regional heterogeneity resulted in diverse trajectories of settlement proximity to major rivers, with the attractiveness of rivers increasing in arid regions and decreasing in humid areas. Our results reveal a historical coevolution of human-water systems, which could inform water management and contribute to societal adaptation to future climate change.

The Evolution of Metropolitan’s Agricultural Partnerships

Metropolitan Water District of Southern California (MWD) | August 5th, 2022

The Evolution of the Urban Infrastructure in the Nineteenth and Twentieth Centuries

National Academy of Sciences (NAS) | December 3rd, 1984

This chapter* discusses the origins and development of the urban capital infrastructure in the United States since 1790. Urban infrastructure is defined as the "sinews"

This chapter* discusses the origins and development of the urban capital infrastructure in the United States since 1790. Urban infrastructure is defined as the "sinews" of the city: its road, bridge, and transit networks; its water and sewer lines and waste disposal facilities; its power systems; its public buildings; and its parks and recreation areas.1 In developing an analysis, the chapter draws on history in three ways: to furnish perspectives on the evolution of the urban infrastructure over time; to point to critical stages, paradigm shifts, and key turning points in history; and to provide analogies between the contemporary so-called crisis of the infrastructure and similar events in the past (see Stearns and Tarr, 1982). The chapter is structured around questions concerning the demand for public works; the factors affecting their supply; the character of the provider (public, public-private, or private); and the relationship of urban infrastructure to financial, political, technological, spatial, public health, social, and demographic considerations. *Chapter 1, Perspectives on Urban Infrastructure, edited by Royce Hanson, National Academy Press, 1984

The Extraordinary California Drought of 2013-2014: Character, Context, and the Role of Climate Change

American Meteorological Society (AMS) | September 1st, 2014

The event: 2013/14 drought in California. Nearly the entire state of California experienced extremely dry conditions during 2013 (Fig. 2.1a). Statewide, 12-month

The event: 2013/14 drought in California. Nearly the entire state of California experienced extremely dry conditions during 2013 (Fig. 2.1a). Statewide, 12-month accumulated precipitation was less than 34% of average (Fig. 2.1b), leading to a wide range of impacts. In early 2014, state and federal water agencies announced that agricultural water users in the Central Valley would receive no irrigation water during 2014 (DWR 2014; USBR 2014), and that a number of smaller communities throughout California could run out of water entirely within a 90-day window (USDA 2014a). Low rainfall, unusually warm temperatures, and stable atmospheric conditions affected the health of fisheries and other ecosystems (CDFW 2014), created highly unusual mid-winter wildfire risk (CAL FIRE 2014), and caused exceptionally poor air quality (BAAQMD 2014). Such impacts ultimately resulted in the declaration of a state-level “drought emergency” and the federal designation of all 58 California counties as “natural disaster areas” (USDA 2014b).

The Extraordinary California Drought of 2013/2014: Character, Context, and The Role of Climate Change

American Meteorological Society (AMS) | September 30th, 2014

Nearly the entire state of California experienced extremely dry conditions during 2013 (Fig. 2.1a). Statewide, 12-month accumulated precipitation was less than 34% of

Nearly the entire state of California experienced extremely dry conditions during 2013 (Fig. 2.1a). Statewide, 12-month accumulated precipitation was less than 34% of average (Fig. 2.1b), leading to a wide range of impacts. In early 2014, state and federal water agencies announced that agricultural water users in the Central Valley would receive no irrigation water during 2014 (DWR 2014; USBR 2014), and that a number of smaller communities throughout California could run out of water entirely within a 90-day window (USDA 2014a). Low rainfall, unusually warm temperatures, and stable atmospheric conditions affected the health of fisheries and other ecosystems (CDFW 2014), created highly unusual mid-winter wildfire risk (CAL FIRE 2014), and caused exceptionally poor air quality (BAAQMD 2014). Such impacts ultimately resulted in the declaration of a state-level “drought emergency” and the federal designation of all 58 California counties as “natural disaster areas” (USDA 2014b). *From Explaining Extreme Events of 2013 from a Climate Perspective, Bull. Amer. Meteor. Soc., 95 (9), S1–S96.