We want to make you aware of important changes to how USGS water data will be delivered as we modernize our water data storage and delivery systems. After decades of service, the legacy NWISWeb pages (waterdata.usgs.gov) and related tools—including Water Services and WaterWatch—will be retired. Some groundwater features are already frozen, and access to most NWISWeb pages will end by March 2026.

• The way you access USGS water data is changing, but the data itself will remain available.
• Legacy NWISWeb pages will begin redirecting to Water Data for the Nation (WDFN) tools and services. Most redirects will be complete by March 2026.
• APIs will remain available longer but are scheduled for decommissioning in early 2027. We encourage API users to begin transitioning now to avoid disruptions.
• New features include modern APIs, interactive maps, charts, and tables for exploring water data.

• If you rely on NWISWeb pages or Water Services for data access, start transitioning to WDFN tools and APIs now.
• Update any bookmarks or scripts that point to legacy URLs. Redirects will remain in place for about a year after March 2026, but old links will eventually stop working.
• To learn how to update common workflows, please see NWISweb Decommission Campaign 2 | Water Data For The Nation Blog 

• Tutorials and resources.
• Subscribe to the WDFN Newsletter.
• Check out the public webinar recording.
• Questions? Email: GS-W_Waterdata_Support@usgs.gov.

We appreciate your interest in USGS water data are here to help make this transition smooth. Please reach out with any questions or concerns.