USGS Integrated Water Science Basins: 10 River Basins to Forecast the Nation's Water

From the U.S. Geological Survey's series Water Priorities for the Nation, July 2021.

The United States faces growing challenges to its water supply, infrastructure and aquatic ecosystems from population growth, climate change, floods and droughts. To meet them, the USGS Water Resources Mission Area is combining recent advances in monitoring, research and modelling to improve assessments of water availability across the country. A key part is the intensive study of 10 Integrated Water Science (IWS) basins between 2019 and 2028.

Ten basins to stand for the nation

The basins, each 10,000 to 20,000 square miles, are chosen to represent large regions of the country and a range of threats to water quantity and quality. What is learned in them — about how climate, human activity, surface water, groundwater, water quality, and supply and demand interact — will help quantify and forecast water availability for their regions and, ultimately, the nation.

The strategy for each basin draws on:

1. stakeholders' views of the most pressing regional water issues and information needs;
2. a catalogue of existing data, observation networks and models that could help assess water availability in the basin and region;
3. the data and research gaps that limit how accurate basin models are and how widely they apply.

Targeted new observations and research then fill those gaps, leading to better understanding of what limits water availability, more accurate basin and regional models, and better information and predictions about the nation's water, now and in the future.

The USGS frames the work as four linked steps — observe, understand, predict and deliver. Each depends on the others: without advanced observation, understanding is limited, and so is the ability to build better predictive models. That is why the USGS makes integrating its science a priority.

Figure 1. Candidate hydrologic regions for the IWS basins, with the first three basins outlined. Basemap source: U.S. National Park Service. Credit: U.S. Geological Survey.

Choosing the basins

Basins are selected by combining stakeholder input with objective, quantitative rankings that take account of environmental, engineered and social settings, ecological resources, water demand, water quality and quantity, and changes to water resources in different regions. The result is to be a representative set of basins with varied water availability and use.

More basins are to be added each year, as funding allows, through 2028, until work is under way in all 10.

The first three

Delaware River Basin. Its water managers have a long record of innovative regional solutions for a resource that supplies drinking water to more than 17 million people. USGS science here supports modern prediction and decision-support systems for a nationally important, complex interstate river. In 2019–20, for example, the USGS deployed autonomous underwater vehicles in the lower Delaware River to learn more about the processes affecting current velocity, salinity, water temperature and water quality in the Delaware Estuary — data that will inform models of how flow management and sea-level rise affect the intrusion of salt water.

A bridge over the Delaware River at Narrowsburg, New York. Credit: U.S. Geological Survey.

Upper Colorado River Basin. The USGS is building integrated data and models of streamflow, groundwater, evapotranspiration, snowpack, soil moisture, water quality and water use to inform assessments of water availability. Linking data directly to models here should improve water prediction in other snowmelt-driven systems in the Rocky Mountains and beyond, and help assess water availability and quality and the effects of short-term climate disturbances, such as fire and drought, and of long-term climate change. For example, the USGS is developing advanced methods to estimate how snow water equivalent varies across the landscape, to be built into models that predict the volume, timing and duration of streamflow from snowmelt.

The Colorado River near Grand Junction, Colorado. Credit: U.S. Geological Survey.

Upper and Lower Illinois River Basins. These basins are challenged by too many nutrients — mainly nitrogen and phosphorus — and the harmful algal blooms that heavy nutrient loads can cause. With extensive urban and agricultural land, they are an ideal place to learn how nutrient sources, together with climate and land-use change, may limit water availability.

A barge on the Illinois River. Credit: U.S. Geological Survey.

Sources

• Miller, M.P., Eberts, S.M., and Sprague, L.A., 2021, Water priorities for the Nation — USGS Integrated Water Science basins: U.S. Geological Survey Fact Sheet 2021–3041. https://doi.org/10.3133/fs20213041
• The fact sheet cites the National Academies of Sciences, Engineering, and Medicine (2018), Van Metre and others (2020), Hutson and others (2016), Leland and Porter (2000) and Panno and others (2008).
• The introduction, the Upper Colorado section, the map and the photographs are taken from the fact sheet's PDF; the imported text lacked them.
• Rewritten in hubnx's own words.