HERO E&C has launched the Texas Rain & Stream Gage Map, a free map of the latest rain, river stage, and streamflow readings from U.S. Geological Survey (USGS) and National Weather Service (NWS) gages across Texas. It runs in a web browser at heroenc.com/gage-map, with no account and no fee, alongside the other HERO E&C Free tools.
Not a flood warning system. In an emergency, call 911. For flood warnings, go to weather.gov.
What it shows
Each reading shows its value, time, and age, and is marked provisional. Where NWS sets flood stages, gages at action stage or above are colored by NWS flood category — action, minor, moderate, or major — as reported by NWS. NWS also carries many river authority, county, and city gages, and the map names the agency that supplied those readings.
For rain, the map shows USGS rain gages, NWS multisensor rain totals (radar and rain gages, about 4 km cells) for 1 hour to 7 days, and CoCoRaHS volunteer daily reports. It also marks Harris County Flood Control District and TWDB TexMesonet gage locations, with links to the operator’s readings. Below the map, a county-by-county directory lists state, river authority, county, and city gage networks with links to their own maps and data.
How to use it
Find a gage by name, river, county, or USGS or NWS ID, or click it on the map. The gage view shows the latest readings, NWS flood stages where they exist, and a chart for the last 24 hours, 7 days, or 30 days. “Download CSV” saves those readings as each agency reported them, and links open the USGS and NWS pages for the gage and the USGS download for longer records.
Enter a Texas address, coordinates, or a site boundary, or click anywhere on the map, to list the gages within 10 miles, the NWS rain total estimates at that spot, and the networks that cover the county. “Gages upstream and downstream” follows the main stream for up to 50 miles. A statewide CSV saves every reading on the map, and the page checks for newer readings every 15 minutes while it is open.
Who it is for
The map is built for drainage and floodplain engineers, hydrologists, and city, county, and river authority staff who need to see what gages are reporting near a project, pull a recent record into a spreadsheet, or find out who runs the gage on a given creek. The readings are spread across many agency websites; the map puts the federal and volunteer readings on one screen and links to the rest.
What it is not
The readings are provisional: the agencies can revise them, and a reading can be late, missing, or wrong. Each reading shows its time. Not every local gage is on the map; many county and city gages are reached through the directory links instead. NWS flood categories describe conditions at the gage; flooding can happen where there is no gage. If an agency does not respond, the map says so. Check a reading on the agency’s own page before using it for design, construction, bidding, or permitting.
Not a flood warning system. In an emergency, call 911. For flood warnings, go to weather.gov.
Data and technology
Readings come from USGS Water Data for the Nation, the NWS National Water Prediction Service, NWS multisensor precipitation estimates, and the CoCoRaHS network (CC BY 4.0). The directory also links to the USGS National Water Dashboard and TexasFlood.org. Requests run from the visitor’s browser directly to each agency; HERO E&C does not receive or store searches, files, or results. The map is built with the ArcGIS Maps SDK for JavaScript.
Try it on your next project
HERO E&C is a San Antonio civil and water resources engineering firm founded in 2025 and led by Dr. Seoyoung Kim, Ph.D., P.E., CFM. When a project needs a hydrologic model, a drainage study, or floodplain work built on site-specific data, HERO E&C can help.