Flooding causes more deaths and property damage in the U.S. than any other severe weather-related event. A mere six inches of fast-moving water can knock over an adult. It takes only two feet of rushing water to carry away most vehicles, including pickups and SUVs. The roadbed can wash away or be concealed by the floodwaters, making it easy to trap vehicles.

Texas is prone to extremely heavy rains and flooding. Bexar County in central Texas, about 190 miles west of Houston, is particularly vulnerable because storms stall along the Balcones escarpment. This region is known as the Texas Hill Country and has earned the nickname “flash flood alley.” As an example, for the period of 1973 through 2000 in south central Texas there were 274 weather-related deaths. Of those, 74 percent were flood or flash flood related and 67 percent involved vehicles.

Improving public safety

An example of an advance warning site in Bexar County, Texas

A well-designed system can improve traffic safety and provide more thorough roadway condition forecasting and better responses to roadway flooding events. HSE’s is comprised of a master gauging site, which is located at the stream site and uses a highly accurate sensor to determine the water level. When preset upper and lower thresholds are met, the master site commands the remote sites to turn their beacons on or off and/or activate barrier gates depending on the current flood stage. Communications between the master and remote sites are normally wireless and most are solar powered.

Comprehensive software tracks all the gauging data, system status and events and can send text messages, pages or emails directly to personnel. Data from the base station software can also be fed to other databases in order to populate agency or public websites.

Bexar County, Texas

In order to better prepare residents, Bexar County officials implemented a high water detection system in 2007. The HSE system consisted of four rain and stream gauging sites, which monitor conditions on low points on two separate roadways. When water threatens to flood the road, it automatically activates flashing beacons to warn motorists.

Pleased with the success of this system, the county awarded a contract to HSE in July 2009 for the implementation of additional flooded roadway warning systems. The county now operates two base stations for monitoring and collecting data, 12 gauging sites and 27 warning stations with flashing beacons to monitor flooding conditions. According to Roy Alaquinez of the public works department, “High Sierra has managed the project in a professional manner. From hardware installation to software set-up and configuration, the system has performed and has helped our agency improve safety measures for area residents and visitors.”

For additional information, visit www.highsierraelectronics.com or call (800)-275-2080.