	Introduction

The 116 th Congress may conduct oversight and deliberate on authorizations and appropriations legislation related to water resource development, management, and protection. Development pressures, droughts and floods, and concerns about changing hydrology fro m land-use change and climate change engender nonfederal interest in federal financial and technical assistance for water resource science and projects. There is interest in new water resource infrastructure (e.g., storm surge gates, water storage) and new kinds of projects (e.g., groundwater recharge projects, nature-based flood risk reduction). Historically, Reclamation constructed projects in the 17 arid states west of the Mississippi River; these projects were designed principally to provide reliable supplies of water for irrigation and some municipal and industrial uses. USACE constructs projects nationwide that primarily seek to improve navigation, reduce flood damages, and restore aquatic ecosystems. In addition, Congress authorizes and funds selected water resource science and monitoring activities at multiple federal agencies. This report first discusses some broad categories of water resource topics relevant to the 116 th Congress—projects and activities of USACE, western water and Reclamation, Indian water rights settlements, international waters shared with Canada and Mexico, and water resource science at USGS. The report next covers the following crosscutting topics:
funding and financing aging and new water resource projects, changing from federal infrastructure projects to federal partnerships, protecting and restoring the environment, flood resilience and natural and nature-based infrastructure, and recharging groundwater. Some USACE-related issues that the 116 th Congress may address include the following:
Funding and financing issues, such as the use of the Harbor Maintenance Trust Fund, investments in projects to deepen coastal harbors, USACE budgeting priorities, and oversight of USACE efforts to implement public-private partnerships and to develop alternative financing opportunities. Policymakers may consider whether—and, if so, how—to advance projects in the backlog. Several Reclamation-related water project and management issues may be the subject of legislation or oversight during the 116 th Congress. Such issues may include, for example, the status of new and proposed water storage projects; dam safety issues at existing federal reclamation projects; and efforts to address the agency's aging infrastructure and transition projects to nonfederal ownership. In addition, Congress may address drought mitigation assistance, planning, and preparedness through oversight hearings and legislation (e.g., Energy and Water Development appropriations), especially if dry conditions persist or intensify in the Colorado River basin and in other western states. Other river basins generating regular congressional interest include the Colorado River, Columbia River, Klamath River (California and Oregon), and Rio Grande River basins. Since 2014, Congress has directed the U.S. Department of State to report annually on Mexico's deliveries and on efforts to improve Mexico's treaty compliance. The 116 th Congress may consider the status and priority of federal efforts to restore large-scale aquatic ecosystems that have been altered or impaired by development, habitat loss, and federal water resource projects. Congress may look at the funding and performance of existing restoration efforts. Decisionmakers also may evaluate restoration initiatives on how well they balance demands for water resources and species' conservation needs. Approaches that mimic nature and are "nature-based" are used as part of flood management and risk reduction. Interest in the nation's infrastructure and changes in environmental conditions (e.g., hydrologic conditions associated with a changing climate) may prompt the 116 th Congress to examine the implementation and funding of nature-based infrastructure, and protection of natural features that reduce flood risk. Federal Water Resource Infrastructure

Most of the large dams and water diversion structures in the United States were built by, or with the assistance of, the Bureau of Reclamation (Reclamation) or the U.S. Army Corps of Engineers (USACE).
The 116th Congress may conduct oversight and deliberate on authorization and funding of water resource development, management, and protection. Congress engages in authorization and appropriations for water resource projects and activities of the U.S. Army Corps of Engineers (USACE) and the Bureau of Reclamation (Reclamation). USACE constructs projects nationwide, primarily to improve navigation, reduce flood damage, and restore aquatic ecosystems. Reclamation constructs projects in the 17 arid states west of the Mississippi River; these projects primarily provide water supply benefits, often to agricultural irrigation users. The 116th Congress, like earlier Congresses, also may consider Indian water rights settlements and may evaluate the focus of and funding for the water resource science activities of the U.S. Geological Survey (USGS).
Development pressures, droughts and floods, and concerns about changing hydrology from land-use change and climate change have engendered nonfederal interest in federal financial and technical assistance for water resource science and projects. Stakeholders are interested in a range of water resource issues, including
new water resource infrastructure (e.g., storm surge gates, water storage) and new kinds of projects (e.g., groundwater recharge, nature-based flood risk reduction); reinvestment in aging water resource infrastructure and use of water science and real-time monitoring and forecasting to improve infrastructure operations; funding and financing of projects, and whether and how to shift from federally led projects to federal partnerships with state and/or local entities; and activities to protect and restore aquatic ecosystems and enhance flood resilience (including the use of nature-based approaches).
Some topics arise within the context of specific agencies. USACE-related topics for the 116th Congress may include funding and financing issues, such as use of the Harbor Maintenance Trust Fund; the status of investments in projects to deepen coastal harbors; USACE budgeting priorities; and oversight of USACE efforts to implement public-private partnerships and develop alternative financing opportunities. Some Reclamation-related water project and management issues during the 116th Congress may include the status of proposed new and augmented water storage projects, as well as efforts to address the agency's aging infrastructure and transition certain qualifying projects to nonfederal ownership. Congress also may address Reclamation drought mitigation activities in the Colorado River basin and other areas. In addition, Congress may explore ongoing issues associated with Reclamation's project operations in California and other areas. It may address how these issues affect water deliveries to irrigation districts and municipalities and threatened and endangered species, among others.
Some topics are international in character. Regarding freshwater bodies shared with Canada, potential topics for the 116th Congress include federal funding for activities supporting Great Lakes restoration and negotiations (and any resulting agreements) with Canada to modify the Columbia River Treaty. Potential topics related to Mexico include oversight of a binational agreement on water sharing during dry conditions in the Colorado River basin and Mexico's deliveries to the United States in the Rio Grande basin.
Crosscutting topics (i.e., topics relevant to multiple agencies and programs) also are part of congressional water resource deliberations. For example, the 116th Congress may consider the status and priority of new and ongoing federal efforts to restore large-scale aquatic ecosystems that have been altered or impaired by changes to their natural conditions (e.g., Florida Everglades, Chesapeake Bay). Congress may explore the funding and performance of existing restoration efforts, including what changes (if any) may be necessary to improve project delivery and evaluation. The 116th Congress may consider its guidance to multiple federal agencies on how to respond to flood hazards, including efforts related to enhancing the resilience of infrastructure and communities to flooding. There is interest in developing and evaluating approaches that protect natural elements that reduce flood risk (e.g., natural dunes) or are "nature-based" in comprehensive flood risk management (e.g., constructed dunes). Congress also may consider legislation and oversight on USACE supplemental appropriations for response to and recovery from floods.