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A Dangerous Case of Missing Water. (Part Ten)

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It’s the evening of July 15 th 2021 in the Valley of Ahr, Germany. Heavy rains are predicted and this is the fourth day of constant flood warnings issued by the German Meteorological Service. The Ahr River is equipped with a total of 8 supporting river gauges, four on the main tributary, and four on smaller feeders. The first gauge was installed in 1946, the newest in 1988. Based on modeling, a river rise of approx. 19 feet was forecast (ref 1). This would have kept water largely within the banks and town leadership did not evacuate. This decision would prove catastrophic.   The water arrived shortly after midnight. It was 34 feet, not 19 feet.   It was also too late to evacuate and   139 people lost their lives in this valley alone. Why was the forecast off so much? Germany had just spent tens of millions on the European Flood Awareness System (EFAS). This river had 54 prior recorded flood incidents over centuries of settlement. 73 years of river gauge monitoring exis...

Water Science vs Military Science (Part Ten)

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  Photo: River Sentry Founder Ian Cunningham in a prior Naval Aviation Instructor Role. Preventing flash flood casualties has long been the domain of hydrologists, scientists, engineers, and academics. The methods and tools vary in complication and process, but the end pursuit is the same; provide decision makers with advance warning of impending flood conditions. During daytime and in flatter topographical areas, there have been successes. At night in the mountains, the pursuit has been deadly. River Sentry is comprised of military war planners. Our expertise is guarding threatened real estate and lives from the most lethal and unpredictable threats our adversaries might invent. Threats are studied, classified, then mitigated with technology, tactics, and procedures. The process is effective and works here. Flash Floods are easily defined as a six-parameter threat further described as an “unpredictable, unstoppable, time critical, detectable, single direction, lethal threat”. ...

River Sentry Project RIVER SHIELD GUADALUPE commences! (Part Nine)

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Over the holidays, River Sentry formally committed to installing 100 flood warning towers along the Guadalupe in Kerr County before campers return this summer. The project is privately funded by donors and an association of youth camps that is represented by Camp Mystic. River Shield will encompass both the North Fork, South Fork, Honey Creek, and Turtle Creek with the goal of providing localized flood warning protection for all youth camps in the area. After the installation is complete, River Sentry will also build a mobile app that will allow the public, including camp parents, to see the location and status of all sensors located along the rivers. This is expected to be launched later this year. “This is to build trust” River Sentry Founder and CEO Ian Cunningham explains. “We are building the most advanced and capable collection of flood warning systems that exists anywhere. We want people to see it, understand it, and if desired, interact with it.” The River Sentry design i...

River Sentry: New Tech for a new Flood Code (Part Eight)

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We have now covered detection, false alarms, and trust but the effective escape loop is not complete. For the final solution, we must address sleep and proximity. Proper mitigation requires solutions in varying scenarios including those clear, but adjacent to flood plain boundaries. Recent Texas “SB1 Camp Safety” legislation reduces risk for youth camps by elevating lodging outside the flood plain. This only reduces risk; it does not eliminate it. On July 4 th, significant flooding occurred outside the 100-year flood plain. Rio Ancho, an upscale gated subdivision on the San Gabriel experienced significant flooding. Several residents required rescue from their homes. Several miles away, Sandy Creek, a minor tributary in Travis County, tore through a neighborhood resulting in ten deaths. Just north in Williamson County, an unfortunately named “Little Creek” over flowed and swept away a woman in her residence behind the Hope House family shelter. Furthermore, all of this occurred dur...

River Sentry T100. Trust factor and preventing flood tragedies. (Part Seven)

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From 2010 to 2020, Under the EU Copernicus program, Germany and Belgium worked together to build a cutting-edge Flood Early Warning System (FEWS) that would be collectively known as the European Flood Awareness System (EFAS). It was for good reason as floods have long plagued the region. The worst occurred in 1962 killing 362 people in Hamburg. EFAS was the pinnacle with tens of millions spent on the most modern sensors and software available. On July 11 th , 2021, EFAS began the first of days of increasingly severe flood warnings with associate rain fall predictions. In the Valley of Ahr, these warnings were met with little apparent effect. On the afternoon of July 15 th , rain predictions foretold a river rise of 19 feet, an apparently acceptable risk for local leadership. Evacuations were not ordered. An additional flood warning was issued at 3PM. The local population seemed unfazed, perhaps desensitized by lesser floods in what was a common flood prone area. The multitude of warn...

River Sentry: FAR 0 and the Wolf Ratio! (Part Six)

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False Alarm Ratio (FAR) is the measure of alerts to actual events. A missed significant flood event could be a devasting failure for a Flood Early Warning System (FEWS) however, this only affects Probability of Detection ratios (POD). What if you successfully predict a flood event, issue a warning, and it still results in incredible tragedy? How do we account for this? A missed flood event is a significant failure, but a high FAR score is a slow death of 1000 cuts. There are no free warnings, and each unconfirmed notification slowly degrades system legitimacy. This simple human behavior equation was first captured by the ancient Greek storyteller Aesop, who famously titled the fable, “The Boy Who Cried Wolf”. FEWS purveyors attempt to capture this through FAR scoring but this doesn’t capture the totality of the problem. Flooding can be highly localized. If a flood warning is issued for a 200-square mile area affecting 10 tributaries and flooding occurs on one tributary, the FEWS wa...

River Sentry: The pursuit of perfection, POD 1 (Part Five)

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Probability of Detection (POD) ratio is the major metric of the Flood Early Warning Systems (FEWS) arena. It is the measure of events divided by warnings plus missed events. The perfect ratio is 1 flood warning per flood event, no missed events. A 1/1 ratio can simply be expressed as 1…perfection.   It sounds simple, it is anything but. The European Flood Awareness System (EFAS) is estimated to have cost over $30 million and hovers around POD .70. That ratio falls in the more mountainous and remote areas. How is some unknown new tech company in central Texas going to beat that kind of score? It’s a great question, let’s explore it. Before we compare apples, let’s define the arena. EFAS is a regional system attempting to provide flood warning over a large geographic area utilizing a myriad of sensors and software solutions to provide predictive warnings prior to an actual flood event.   River Sentry builds localized area protection with additional downstream advanced warn...