The Cost of Rehabilitating Dams in the U.S.

Association of State Dam Safety Officials (ASDSO) | August 7th, 2025

In 2022, the ASDSO Board of Directors established a task force to review and update the methodology and processes that were developed several years earlier by ASDSO to es

In 2022, the ASDSO Board of Directors established a task force to review and update the methodology and processes that were developed several years earlier by ASDSO to estimate the costs to rehabilitate non-federal dams in the United States (U.S.). This was a one-year project financed by ASDSO. The updated methodology and processes used readily available data to estimate the number of dams in need of rehabilitation based on dam height, age, and Condition Assessment rating. Data from more than 500 dam rehabilitation projects nationwide, ranging from $10,000 to more than $500 million, was used in determining the total amount of funding needed for dam rehabilitation at a national level. The purpose of this report is to inform national and state policy decisions and provide the public and the media with a high-level understanding of the national dam rehabilitation need in terms of estimated costs. The findings and methodologies are not meant to be used to estimate a specific dam rehabilitation cost.

The economic value of local water supplies in Los Angeles

Nature Portfolio (Springer Nature) | May 21st, 2018

Los Angeles imports water over long distances to supplement local supplies. Reduced reliability of the available imports is driving many local agencies to promote conserv

Los Angeles imports water over long distances to supplement local supplies. Reduced reliability of the available imports is driving many local agencies to promote conservation and enhance local water sources. These include stormwater capture, water reuse and groundwater. But financial considerations are often a significant impediment to project development, especially when comparing new and existing sources. Here we demonstrate a comprehensive approach for evaluating the economic implications of shifting to local water reliance in Los Angeles County. We show that local water supplies are economically competitive. Results from integrated hydroeconomic modelling of urban water in Los Angeles identify cost-effective water supply portfolios and conservation targets. Considering costs across the ‘full-cycles’ of urban water supply that span agency boundaries yields better comparisons of planning alternatives. Throughout the region, many water retailers could successfully mitigate effects of imported water cuts while still supporting drought-tolerant landscapes, but some would suffer due to over-reliance on imports. Updating economic assessment methods would support needed innovations to achieve local reliance in Los Angeles, including infrastructure investments, institutional reforms, many more drought-tolerant landscapes and reallocated groundwater rights.

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 Future of Agriculture in the San Joaquin Valley

Public Policy Institute of California (PPIC) | February 9th, 2023

The Governance Gap: Climate Adaptation and Sea-Level Rise in the San Francisco Bay Area

University of California, Davis (UC Davis) | June 27th, 2017

This report summarizes the results of an extensive study of governance for climate adaptation and sea-level rise in the San Francisco Bay Area (SF Bay Area), wh

This report summarizes the results of an extensive study of governance for climate adaptation and sea-level rise in the San Francisco Bay Area (SF Bay Area), where the concept of sea-level rise adaptation also includes coastal flooding from high tides and extreme storm events. We focus on the “governance gap” that exists between the problem of sea-level rise and the implementation of adaptation solutions that increase resilience. We take a broad view on governance as the set of institutional arrangements, governmental authorities, and public stakeholders who collectively plan and implement adaptation activities, including identifying funding strategies and the agreeing on the information basis for decision making. While most stakeholders recognize the risk of sea-level rise and other climate impacts, and have good ideas about potential on-the-ground solutions, realizing these solutions requires overcoming a series of governance challenges. All of these governance challenges are barriers to stakeholder cooperation at multiple geographic levels—local, regional, state, and federal. There are many different governmental and non-governmental actors facing the same sea-level rise problem (in “the same boat”), and coordination is required to have them “row in the same direction.” The imperative for multi-level cooperation becomes more poignant as the science on sea-level rise continues to advance, and considers the possibilities of higher average levels of sea-level rise and rapid and extreme sea-level rise due to accelerated melting of the Antarctic ice sheet. This report summarizes the major challenges, identifies the menu of possible solutions, and develops some specific recommendations on the next steps needed to remedy the governance gap and enhance the adaptive capacity of the SF Bay Area. The governance analysis is a component of the larger UC Davis/Berkeley research project called Resilience of Infrastructure as Seas Rise (RISeR), See Figure 1, which is funded by National Science Foundation to analyze the interactions between sea-level rise adaptation, transportation infrastructure, and governance in the SF Bay Area. The governance analysis was conducted in Fall 2016-Winter 2017, and is based on a qualitative case study that combines in-person interviews, focus groups, document analysis, and content analysis of interview responses. The draft report was made available to study participants in Spring 2017, along with two webinars for receiving feedback. Participants included leaders of governmental and non-governmental organizations across the SF Bay Area region. The research focused mainly on sea-level rise and coastal flooding, but also linked to broader issues of climate adaptation when appropriate. Focus groups deliberated on the best possible solutions to solving the identified governance challenges. Respondents identified the overarching governance challenge as the imperative for multi-level cooperation among all sea-level rise adaptation stakeholders. Sea-level rise adaptation entails interdependencies, where the vulnerabilities and adaptation decisions of local actors impose regional costs and benefits. While regional cooperation is beginning to emerge, most stakeholders see a critical need for shared learning, coordination and planning. The recommendations provided in this report are intended to accelerate the processes of learning and cooperation needed to address the increasingly urgent problem of sea-level rise and coastal flooding.

The importance of system configuration for distributed direct potable water reuse

Nature Portfolio (Springer Nature) | April 27th, 2020

Water and wastewater infrastructure worldwide faces unprecedented demand and supply conflicts that require unconventional solutions. In this study, we develop a novel mod

Water and wastewater infrastructure worldwide faces unprecedented demand and supply conflicts that require unconventional solutions. In this study, we develop a novel modelling framework to assess the environmental and economic implications of a hybrid water supply system that supplements a centralized surface water supply with distributed direct potable reuse (DPR) of municipal wastewater, as a strategy to address such challenges. The model is tested with real water and wastewater systems data from the City of Houston, Texas. Results show that supplementing the conventional centralized water supply with distributed DPR would reduce water age in the drinking-water distribution network and hence improve water quality; properly designed system configurations attain system-wide net energy savings even with the high energy consumption of existing technologies used for advanced treatment of the wastewater. A target energy efficiency for future advanced treatment technologies is identified to achieve net energy saving with all hybrid system configurations. Furthermore, distributed DPR remains financially competitive compared with other unconventional water supply solutions. The modelling framework and associated databases developed in this study serve an important research need for quantitatively characterizing distributed and hybrid water systems, laying the necessary foundation for rational design of integrated urban water systems.

The Metropolitan Aqueduct: Colorado River Water for Cities in the Metropolitan Water District

Metropolitan Water District of Southern California (MWD) | March 12th, 1931

The Newest Plan of Los Angeles Engineers to Provide More Water for that Enterprising Metropolis

Scientific American | February 1st, 1925

The Pine Flat Project on Kings River, California

Kings River Water Users Committee | December 1st, 1979

The Resilience Value of Recycled Water for Los Angeles

University of California, Los Angeles (UCLA) | November 13th, 2024

In 2019, the City of Los Angeles (City) announced the development of the Operation NEXT Water Supply Program (Operation NEXT or Program) (City of Los Angeles, 2019), an a

In 2019, the City of Los Angeles (City) announced the development of the Operation NEXT Water Supply Program (Operation NEXT or Program) (City of Los Angeles, 2019), an advanced water recycling project aimed at expanding the use of purified recycled water. The current approach for Operation NEXT (now Pure Water Los Angeles) encompasses several distinct water infrastructure components. One is the construction and operation of an advanced water treatment purification facility at the Hyperion Wastewater Treatment Plant, the largest wastewater treatment facility west of the Mississippi. This project, in partnership with Los Angeles Sanitation & Environment comprises the Hyperion 2035 Program (Hyperion 2035) (LADWP, 2024; LASAN, 2024). Once constructed, potable recycled water flows from this facility will further diversify the City’s water supply portfolio, adding up to 257,636 acre-feet of supply each year once it is fully operational. A second component of Operation NEXT is a conveyance system that will transport this purified recycled water to groundwater basins or further treatment facilities, where it will be stored or blended with other water supplies. Currently, the construction and operation of Operation NEXT is still being estimated, and costs range between $6.4 billion and $24.0 billion USD as of 2020.