Analysis of USGS Surface Water Monitoring Networks
The issue: National interests in water information are important but challenging to incorporate into planning and operation of a monitoring network driven by local information needs. These interests include an understanding of the spatial variability in water availability across the United States, anthro-physical factors including climate and land use that affect water availability, and federal administration of land and water resources.
How USGS will help: Analysis of how streamflow and other surface-water monitoring networks cover, resolve, and represent variables of national interest can inform network planning and operation.
Problem: The US government and its non-federal partners invest more than $190 million annually to monitor streamflow in the United States at sites where the United States Geological Survey (USGS) operates streamflow gages. The locations of sites in the USGS network are determined by a variety of considerations: local needs and the availability of funding; federal interests in treaties and inter-state water resources management; and the value of long-term, continuous records of streamflow particularly for assessing hydrologic effects of climate change and use. Local needs for streamflow information include flood warning, navigation, infrastructure planning and operation across many different sectors (transportation, energy, agricultural, industrial, residential), management of ecological resources, and recreation. Local needs for streamflow information exceed the resources available for the USGS streamflow monitoring network, so monitoring locations must be prioritized. While network prioritization requires policy decisions that balance different interests, objective analysis of gaps in the network using standardized criteria can inform network planning.
Objectives: This project will develop a consistent methodology for analyzing the coverage, resolution, and representation of the USGS streamflow and other surface-water monitoring networks. The methodology will be implemented for variables related to a broad range of national interests in streamflow information using the streamflow gaging network active in water year 2020. Priority areas for maintain or adding gages will be identified. The methodology will be scalable from the entire United States down to major river basins (4-digit hydrologic unit codes), accommodate new national data sets, and repeatable as the network changes.
Relevance and Benefits: The results of the Network Analysis project will inform planning and operation of monitoring networks for the Federal Priority Streamgage Program, Integrated Water Science (IWS) river basins, and Next Generation Water Observing Systems (NGWOS). The results will identify priority areas for different national interests in streamflow information that can be used to identify where priorities are aligned with multiple interests and, thus, serve the public broadly.
Approach: The approach is based on the National Hydrography Dataset and the locations of active USGS streamflow gages as a spatial framework. A set of variables representing a broad range of national interests in streamflow information is identified. The spatial distribution of each variable is analyzed using its cumulative distribution to assess network coverage, resolution, and representation and to identify priority areas for gaging. The results are available in tabular form as web-based maps.
Network Analysis of USGS Streamflow Gages (ver. 2.0, May 2023)
A general approach for evaluating of the coverage, resolution, and representation of streamflow monitoring networks
Streamflow monitoring network analysis
The issue: National interests in water information are important but challenging to incorporate into planning and operation of a monitoring network driven by local information needs. These interests include an understanding of the spatial variability in water availability across the United States, anthro-physical factors including climate and land use that affect water availability, and federal administration of land and water resources.
How USGS will help: Analysis of how streamflow and other surface-water monitoring networks cover, resolve, and represent variables of national interest can inform network planning and operation.
Problem: The US government and its non-federal partners invest more than $190 million annually to monitor streamflow in the United States at sites where the United States Geological Survey (USGS) operates streamflow gages. The locations of sites in the USGS network are determined by a variety of considerations: local needs and the availability of funding; federal interests in treaties and inter-state water resources management; and the value of long-term, continuous records of streamflow particularly for assessing hydrologic effects of climate change and use. Local needs for streamflow information include flood warning, navigation, infrastructure planning and operation across many different sectors (transportation, energy, agricultural, industrial, residential), management of ecological resources, and recreation. Local needs for streamflow information exceed the resources available for the USGS streamflow monitoring network, so monitoring locations must be prioritized. While network prioritization requires policy decisions that balance different interests, objective analysis of gaps in the network using standardized criteria can inform network planning.
Objectives: This project will develop a consistent methodology for analyzing the coverage, resolution, and representation of the USGS streamflow and other surface-water monitoring networks. The methodology will be implemented for variables related to a broad range of national interests in streamflow information using the streamflow gaging network active in water year 2020. Priority areas for maintain or adding gages will be identified. The methodology will be scalable from the entire United States down to major river basins (4-digit hydrologic unit codes), accommodate new national data sets, and repeatable as the network changes.
Relevance and Benefits: The results of the Network Analysis project will inform planning and operation of monitoring networks for the Federal Priority Streamgage Program, Integrated Water Science (IWS) river basins, and Next Generation Water Observing Systems (NGWOS). The results will identify priority areas for different national interests in streamflow information that can be used to identify where priorities are aligned with multiple interests and, thus, serve the public broadly.
Approach: The approach is based on the National Hydrography Dataset and the locations of active USGS streamflow gages as a spatial framework. A set of variables representing a broad range of national interests in streamflow information is identified. The spatial distribution of each variable is analyzed using its cumulative distribution to assess network coverage, resolution, and representation and to identify priority areas for gaging. The results are available in tabular form as web-based maps.