The U.S. Geological Survey WaterAlert service sends e-mail or text (SMS) messages when certain parameters, as measured by a USGS real-time data-collection station, exceed user-definable thresholds. The development and maintenance of the WaterAlert system is supported by the USGS and its partners, including numerous federal, state, and local agencies.

Real-time data from USGS gages are transmitted via satellite or other telemetry to USGS offices at various intervals; in most cases, once every hour. Emergency transmissions, such as during floods, may be more frequent. Notifications will be based on the data received at these site-dependent intervals.

1. Select Location: Zoom the map into your region of interest or use the Select Location in section below.
2. Select Data Type in section below.
3. Select site using the cursor.
4. Select Subscribe to WaterAlert.

USGS WaterNow

The USGS WaterNow service lets you send a query for a USGS gaging site, via email or cell-phone text message, and quickly receive a reply with its most recent data for one or more of its monitored parameters.

USGS National Water Information System Mapper

The National Water Information System (NWIS) provides access to data at over 1.5 million sites. There are 56 possible site types, including 14 primary and 42 secondary types. Sites may be active or inactive, real-time or historical.

USGS Flood Inundation Mapper

Ths mapping tool shows digital, geospatial, flood-inundation maps of flood water extent and depth on the land surface, with current site conditions.