Handbook for Assessing Value of State Flood Management Investments

California Department of Water Resources (DWR) | June 1st, 2014

Millions of people and over half a trillion dollars in assets are exposed to flood risk in California (DWR 2013a). This remains the case even as State, federal, a

Millions of people and over half a trillion dollars in assets are exposed to flood risk in California (DWR 2013a). This remains the case even as State, federal, and local flood management agencies have worked for decades to reduce the risk and consequences of flooding in the State. The people of California have shown that they understand the increasing flood risk due to population growth, environmental concerns, climate change, and land use practices, and they are willing to invest in flood risk management projects. This requires the public agencies responsible for California’s flood risk management to demonstrate the value of those investments both before and after they are implemented. This Handbook for Assessing Value of State Flood Management Investments (HAV) supports that effort.

Hazy Futures: Projecting the local impacts of global warming is a stubborn challenge. But cities need answers fast

American Association for the Advancement of Science (AAAS) | June 5th, 2025

A wastewater treatment plant isn’t top on everyone’s sightseeing itinerary. But on a cloudless, breezy day in April, Agmed Weber, operations manager for the Walnut Cr

A wastewater treatment plant isn’t top on everyone’s sightseeing itinerary. But on a cloudless, breezy day in April, Agmed Weber, operations manager for the Walnut Creek plant—which handles more than half of the sewage here in Texas’s booming capital city—is an enthusiastic tour guide. He marvels at the foresight of those who built the jumbo plant a half-century ago, when Austin was a third of its current size. “They were really thinking about the future,” he says. Weber feels a similar pressure—to prepare for not only continued population growth, but also a hotter future. Austin is “in a tight space where we need to think ahead,” he says.

High‐resolution surface water dynamics in Earth’s small and medium‐sized reservoirs

Nature Portfolio (Springer Nature) | August 12th, 2022

Small and medium‐sized reservoirs play an important role in water systems that need to cope with climate variability and various other man‐made and natural challenges

Small and medium‐sized reservoirs play an important role in water systems that need to cope with climate variability and various other man‐made and natural challenges. Although reservoirs and dams are criticized for their negative social and environmental impacts by reducing natural flow variability and obstructing river connections, they are also recognized as important for social and economic development and climate change adaptation. Multiple studies map large dams and analyze the dynamics of water stored in the reservoirs behind these dams, but very few studies focus on small and medium‐sized reservoirs on a global scale. In this research, we use multi‐annual multi‐sensor satellite data, combined with cloud analytics, to monitor the state of small (10–100 ha) to medium‐ sized (> 100 ha, excluding 479 large ones) artificial water reservoirs globally for the first time. These reservoirs are of crucial importance to the well‐being of many societies, but regular monitoring records of their water dynamics are mostly missing. We combine the results of multiple studies to identify 71,208 small to medium‐sized reservoirs, followed by reconstructing surface water area changes from satellite data using a novel method introduced in this study. The dataset is validated using 768 daily in‐situ water level and storage measurements (r2 > 0.7 for 67% of the reservoirs used for the validation) demonstrating that the surface water area dynamics can be used as a proxy for water storage dynamics in many cases. Our analysis shows that for small reservoirs, the inter‐annual and intra‐annual variability is much higher than for medium‐sized reservoirs worldwide. This implies that the communities reliant on small reservoirs are more vulnerable to climate extremes, both short‐term (within seasons) and longer‐term (across seasons). Our findings show that the long‐term inter‐annual and intra‐annual changes in these reservoirs are not equally distributed geographically. Through several cases, we demonstrate that this technology can help monitor water scarcity conditions and emerging food insecurity, and facilitate transboundary cooperation. It has the potential to provide operational information on conditions in ungauged or upstream riparian countries that do not share such data with neighboring countries. This may help to create a more level playing field in water resource information globally.

History of the All-American Canal: Boulder Canyon Project

U.S. Bureau of Reclamation (USBR) | December 1st, 2009

A narrative history of the construction of the All American Canal, Imperial Dam, and the Coachella Canal.

A narrative history of the construction of the All American Canal, Imperial Dam, and the Coachella Canal.

Hydroclimatic Extremes as Challenges for the Water Management Community: Lessons from Oroville Dam and Hurricane Harvey

American Meteorological Society (AMS) | December 31st, 2018

Record-breaking extreme storms were a hallmark of 2017 in the United States. An extremely wet winter on the West Coast and brutally damaging hurricane season in

Record-breaking extreme storms were a hallmark of 2017 in the United States. An extremely wet winter on the West Coast and brutally damaging hurricane season in the U.S. Southeast and the Caribbean challenged communities and power-, water- and flood-management systems in ways that raised climate change concerns. Among the most severe were two periods of heavy precipitation and high runoff that exposed dangerous weaknesses in water management infrastructure and land use practices in California and Texas. In California, a record-breaking string of atmospheric river landfalls and remarkably wet winter conditions came close to causing a catastrophic failure of the emergency spillway at Oroville Dam (France et al. 2018; Abbott 2018; White et al. 2019) and less publicized concerns elsewhere (Holland et al. 2018; CNRFC 2017). In Texas, near record-doubling rainfall accumulations from Hurricane Harvey led to massive flooding (Blake and Zelinsky 2018) and dam safety challenges in Houston (Wax-Thibodeaux et al. 2017). We use these events as examples to ground the concept that attribution studies, with careful management-focused framing, can help water management better navigate such unprecedented extremes. *Chapter from the American Meteorological Society's Explaining Extreme Events of 2017 from a Climate Perspective.

Hydrological Intensification Will Increase the Complexity of Water Resource Management

American Geophysical Union (AGU) | March 9th, 2022

Climate change is intensifying the hydrologic cycle, resulting in an increase in floods and droughts. These changes increase the complexity of water resource management t

Climate change is intensifying the hydrologic cycle, resulting in an increase in floods and droughts. These changes increase the complexity of water resource management that must balance between releasing water to reduce flood risk and storing water for long periods without precipitation. Using updated climate model projections, we show that the amount of precipitation during events will become larger combined with longer dry periods where the daily evaporative demand exceeds precipitation for much of the Earth's surface. Additionally, for the late 21st century, a large portion of the years will be hydrologically intense in major river basins, resulting in conditions that deviate from those for which infrastructure and management policies were developed.

Improving Infrastructure for Wildlife

Social Science Research Network (SSRN) | February 25th, 2021

In Washington v. United States, 584 U.S. ___ (2018), the Supreme Court required Washington State to improve fish passage through almost 1,000 culverts originally built to

In Washington v. United States, 584 U.S. ___ (2018), the Supreme Court required Washington State to improve fish passage through almost 1,000 culverts originally built to allow streamflow under roads and highways. The case highlighted conflicts between wildlife needs and infrastructure development. Fish passage through outdated or ill-designed culverts is only a small facet of the larger problem of outdated wildlife infrastructure. Impinged migration corridors for ungulates, turtles, and other mobile taxa; levees disconnecting floodplains from rivers; poor water temperature controls on dams; and eroding ecological productivity accompanying aging of reservoirs exemplify the types of challenges to wildlife created by contemporary infrastructure.

Inaction’s Economic Cost for California’s Water Supply Challenges

University of California, Davis (UC Davis) | May 14th, 2025

California’s water system is in for challenges in coming decades as climate, groundwater policy, and environmental regulations reduce availability and increase variabil

California’s water system is in for challenges in coming decades as climate, groundwater policy, and environmental regulations reduce availability and increase variability in water supplies for agricultural and urban uses. A previous report estimated 4 to 9 million acre-feet (maf) per year of unavoidable reductions in existing water supplies, 12% to 25% of today’s water use (Lund et al. 2024). This report estimates the economic costs of not responding to these reductions in water availability.

Incorporating Sea Level Change in Civil Works Programs

U.S. Army Corps of Engineers (USACE) | December 31st, 2013

Increasingly frequent extreme weather events urge the development of point-of-use water treatment systems

Nature Portfolio (Springer Nature) | August 13th, 2022

The frequency of extreme weather events, including floods, storms, droughts, extreme temperatures, and wildfires, has intensified globally over recent decades due to clim

The frequency of extreme weather events, including floods, storms, droughts, extreme temperatures, and wildfires, has intensified globally over recent decades due to climate change, affecting human society profoundly. Among all the impacts of these extreme weather events, the consequences to our reliable water supply have gained increasing attention as they exacerbate the inequities in health and education, especially in marginalized populations. In this perspective, we emphasize that extreme weather events are able to undermine a stable supply of drinking water through a number of approaches, and conventional centralized water treatment is insufficient at addressing these challenges. We urge that greater recognition, increased public awareness, and more efforts on technological innovation on decentralized, especially point-of-use (POU), water treatment should be prioritized to better help tackle the challenges faced by increasingly frequent extreme weather events.