Hydromet Frequently Asked Questions

How often is the information updated?

Each City of Austin gauge updates data every 15 minutes.

What do the gauges measure?

Some gauges measure how much rain has fallen and others measure how high the water is in a creek.

How is rainfall measured?

Rainfall is measured by a device known as a tipping bucket. Each time 0.04 inches ( 1 millimeter) of rain falls, the bucket tips. A computer records the number of tips or counts. Every 15 minutes, this data is recorded, stored for retrieval, and displayed on the Hydromet web page.

How do I find out how high the water is in a creek?

Select stage from the drop down menu under Hydromet Data.

What does the term stage mean?

The stage indicates the depth of the water at the location of the gauge.

What is streamflow?

Streamflow is the flow of water in the creek. The City of Austin measures streamflow in cubic feet of water per second or cfs.

After clicking on the rainfall amount, what does count refer to in the table?

For City of Austin gauges, a count refers to 0.04 inches (1 millimeter) of rain. For LCRA gauges, a count refers to 0.01 inches of rain.

Counts accumulate over time at each gauge location until the count is reset. The count can be helpful in finding the amount of rainfall over a period of time by subtracting the count at the beginning of the time period from the count at the end of the time period.

How many gauges are in the City of Austin’s network?

The City of Austin has 78 stream level and precipitation gauges on this web site. The City of Austin may periodically add or relocate gauges to meet specific needs.

How does the City choose where to locate a gauge?

The City places gauges based on several different factors including the proximity to areas that may experience flooding, distribution of precipitation gauges in the Travis County area and larger detention dams located within the City of Austin. Gauges are placed on land that is either owned by the City or within the public right of way.

Are there other gauges in the Austin area measuring rainfall?

Yes, both the USGS and LCRA have networks of gauges in Central Texas. View the USGS data. View the LCRA data.

Does the City of Austin use the Hydromet information to issue flood warnings?

No, the National Weather Service issues flood warnings. The National Weather Service Forecast Office, located in New Braunfels, Texas, uses information supplied by several different rainfall sources in Central Texas (including the City of Austin rain gauges) and decides whether to issue flood and weather warnings.

The City of Austin uses the Hydromet information, along with USGS gauge data, to close roads and evacuate low-lying areas.

Have more questions? Call the City of Austin Watershed Protection Department’s Floodplain Office at 512-974-2843.

Data displayed is automatically retrieved and is subject to revision. © 1996-Lower Colorado River Authority. All rights reserved.