When Hurricane Harvey locked its sights on Texas in late August, residents and authorities along the lower Colorado River found the information they might need to make life-or-death decisions online.
The Hydromet monitoring system, a network of more than 275 gauges that continuously update an online map, isn’t new. Its parent agency, the Lower Colorado River Authority (LCRA), has managed it since the 1980s — decades before the term "Internet of Things" (IoT) had even been coined.
It’s also not a flood warning system. Rather, the hydrological data generated by measuring river stages, lake levels and streamflows along with meteorological changes in rainfall, air temperature and humidity, prepares county judges, first responders and residents to make vital decisions.
Improvements to its radio system in 2014 and to its telemetry network in 2016 refresh its map layers — screening data by everything from gauge to region and from streamflow to rainfall — every 15 minutes.
As a result, Hydromet has become indispensable to residents along 600 miles of the Texas Colorado River.
“We were always known as ‘flashflood alley.’ That’s kind of our history here on the lower Colorado River over the past 100-plus years. And so, knowing how much water you’ve got, how fast it’s going and where it’s going really allows us to help with public safety as we inform county judges about their emergency operations,” Phil Wilson, LCRA general manager, said.
Telemetry is the process of collecting and sending data and measurements from remote locations to receivers elsewhere. In Hydromet’s case, its system transmits information on weather, streamflows, water levels and rainfall to repopulate its interactive map every 15 minutes.
The system also provides radar information, and drought and historic data, and lets LCRA coordinate the release of water from its six dams with the U.S. Army Corps of Engineers.
Its expansive reach isn’t cheap; each station of gauges can cost anywhere from around $25,000 to $60,000, and, if built from from scratch today, the entire system would cost around $19 million.
But Hydromet has proven its value. From Aug. 23 to 30, during Hurricane Harvey, pageviews rose by 945 percent compared to Aug. 23-30, 2016. That’s an increase in pageviews from around 50,000 to 475,000. The average time spent on the Hydromet page was 13 minutes, which Wilson characterized as “huge.”
Mindful of its crucial role, the agency is exploring delivering targeted alerts as a possible next step. Earlier this year, LCRA received $650,000 from the U.S. Department of Homeland Security to identify better sensor technologies and software.
LCRA staff determine where the system needs additional gauges based on experience, while taking into account reliability, accuracy and timeliness concerns, and phasing during rain events.
The agency buys items including gauge houses, sensors, and telemetry systems from “a variety of vendors,” it said via email.
LCRA staff then fabricate antenna masts, build the actual gauging stations and install the purchased equipment. LCRA spends around $700,000 annually to operate and maintain Hydromet, and nearly $1 million a year for IT support.
“I think it is also the drive to continue to look at the technology as the means and not the end. We’re always looking for a better way to do this,” said John Hofmann, LCRA’s executive vice president of water.
Two Texas hill country counties largely escaped Harvey’s devastation, but, nevertheless, representatives praised Hydromet for keeping them well-informed to plan responses to fires as well as hurricanes.
Justin McInnis, emergency management coordinator in the office of emergency management in Hays County, which covers 680 square miles south of Austin, said Hydromet provides the agency with valuable “situational awareness.”
“It paints the picture for us better because we can see how quickly the streams are rising. Whatever happens on the west part of the county, at some point is going to get to the I-35 corridor,” McInnis said, noting that Hays County “kind of lucked out” because Harvey’s rains stayed mainly in the east where absorbent clay soils were better equipped to soak them up.
Lower Colorado River Authority
LCRA, which was created in 1934 by the Texas Legislature, has been the primary wholesale electricity provider to the central part of the state since the mid-1930s and is nearly entirely self-funded.
Its duties include operating six dams, providing water to more than 1 million; and managing 600 miles of the Colorado River between San Saba and the Gulf Coast including the Highland Lakes northwest of Austin.
Ron Anderson, emergency management coordinator for Llano County, which spans 966 square miles and stretches east to three members of the state’s Highland Lakes chain, said his region hasn’t had a largescale flood since 1997 and received “really no impact” from Harvey — but likewise praised Hydromet for helping his agency better position resources.
“It’s a tool that we can use on its own, but it’s also something that we use just in concert with the other types of resources at our disposal,” Anderson said, adding: “If we have wildfires going on, we can go into Hydromet and look at relative humidity going on and wind speeds. That’s something that aids us greatly.”
Both officials agreed offering targeted alerts would be a major advancement.
“A lot of times, 15 to 20 minutes of prior knowledge can mean the difference between having to do swift water rescues, having property damage or, God forbid, loss of life, and being able to close off roads to prevent those things from happening,” McInnis said.