In deadly Texas floods, one town had what some didn't: A wailing warning siren

[waterwatcher123]

10. Wow - how much would it cost to install a few sirens and perhaps warning lights?

Most every dam in the country has a warning light attached to it to make sure that the pool height is at or below the design capacity. Otherwise, a spillway or sluice gate could easily fail, and no one would know until the water started to flood adjacent areas. These lights could easily be adapted to a USGS gauge where lights and/or sirens could immediately activate at bank-full to warn vulnerable places (the lights and siren can be located remotely from the gauge). USGS also has a warning system like the NWS for most of their streamflow monitoring sites. However, it does not look like they have the authority to use the wireless emergency alert system. This authority should be changed since USGS and states run most streamflow monitoring stations.

It appears from looking at the satellite imagery of the upper Guadalupe River that extraordinarily little effort has been invested in keeping the upland areas forested. Forests are critical to the storage of water for lots of reasons (trees intercept rainfall, root systems help with infiltration, forest animals who dig provide storage in tunnels and underground homes, and so on). Forests are also typically associated with wetlands and landscapes dotted with wood and landscape depressions). Many of these water holding features are completely absent in pastureland and/or cleared areas. There also appear to be big sections of the river where there is little forest canopy even adjacent to the stream (critical areas for aquatic ecology). Forests cannot stop a huge storm event from producing catastrophic flood conditions. But forests are critical to delaying water that would otherwise be delivered rapidly to river's main channel. The flood hydrograph of the upper Guadalupe mirrors that of a highly developed urban watershed (rapid rise, rapid fall). So, there needs to be a lot more attention devoted to keeping the water on the land. Even allowing beavers to restore the water storage capacity of the upper Guadalupe River would be a good place to start.