Trends Across the Nation

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Environmental Indicators:

Home Temperature Precipitation Drought Sediment

Societal Indicators:

Energy Population Water Use Endangered Species

We live in a dynamic world that constantly changes. We know that climate is changing and that technology can change the amount of water used per person, per crop, or per kilowatt of electricity produced. We introduce new regulations that impact how we manage our water resources, such as protecting threatened and endangered species or protecting water quality. We are surrounded by change.

Here, we document how some conditions relevant to water resources have changed over time:

Environmental
Societal / Regulatory

This project began by exploring how changing conditions may affect U.S. Army Corps of Engineers reservoirs (Corps). As such, we focused how conditions change within different Corps management regions (Districts and Divisions). We also focused on indicators that influence reservoir design and operations (such as precipitation and sedimentation). Societal needs dictate reservoir purposes and influence day-to-day reservoir operations. For example, reservoirs in arid regions may be operated to optimize water supply for irrigation, while reservoirs in humid regions may prioritize flood control. The environmental and societal conditions at the time a reservoir is designed and constructed can be thought of as boundary conditions and these are the conditions that a particular reservoir was initially designed to meet. In the case of the Corps, many reservoirs were built a long time ago: over half of their 537 reservoirs are more than 54 years old.

The past 50 years have seen dramatic changes in climate, population growth and migration, technology and science, policies and regulations. Aging infrastructure presents its own challenges, but those challenges are intensified when coupled with changing conditions, perhaps beyond the reservoir's initial design capacity. There is growing concern that reservoir management, along with other types of water resources infrastructure, needs to proactively adapt operations to effectively manage changing conditions. It is critical to systematically track the broad trends in management-relevant boundary conditions that might affect reservoirs, and in turn, river management. This tool is an effort to compile and visualize a suite of environmental, societal, and regulatory changes pertinent to river management.

The analysis methods are published in the River Research and Applications: Managing Rivers under Changing Environmental and Societal Boundary Conditions, Part 1: National Trends and U.S. Army Corps of Engineers Reservoirs. The data in this visualization tool are all publicly available (except sediment data) and links to those data are found in the Information Tab of each indicator.