People across the country were breathing a deep sigh of relief as the long and devastating 2017 hurricane season drew to a close. As cities across the storm-ravaged areas began the Herculean task of cleaning up and rebuilding, many city planners are looking beyond the immediate clean-up phase, and are determined to build in flood control measures that will help to lessen the impact of future storms.
Many innovative and cutting-edge technologies are being examined, and experts from around the world are being consulted. The Netherlands, with its centuries-old struggle against the sea, is particularly prominent as a place to begin looking for answers; here there is a wealth of expertise and battle-tested technology to be found. Now, many cities in the US are seeking to emulate the success of the Dutch people, and officials are finally beginning to understand that we are now facing a long-term challenge that will only get worse as climate change brings more frequent and more vicious storms.
Enlarged rainfall graphic for Hurricane Harvey in Southeast Texas. Author: David M. Roth; NOAA WPC
In Houston alone, there were over 8 million cubic yards of debris that had to be removed before full attention could be turned to flood prevention projects. There is also an acute housing crisis to be solved; a plan must be developed to shelter all those families that were displaced by the destruction of their homes. But even with these pressing and immediate concerns, planners in Houston are already seeking ways to dovetail flood control planning into every step of the recovery process. This is one of the lessons that the country of Holland has implemented well.
The most obvious flood mitigation project in Houston is to protect, widen, and prevent development around bayous and other water-detention areas; just as Holland has done for hundreds of years. Natural bayous and man-made reservoir projects can absorb a lot of storm water runoff, and if designed or improved with flooding in mind these can channel raging rivers of runoff into a desired direction. However, this obvious priority is too often challenged and circumvented. Houston, like all other growing cities in the US, is increasingly running out of real estate for new housing projects, even as the demand for housing is higher than ever. With the loss of so many homes to the hurricane comes a critical need for the replacement of these structures.
Houston planners understand that a high value must be placed on the flood protection value of its bayous, and they would be wise to resist any temptation to drain or build near these wetlands. But real life often has not worked this way in the past. Many developers have demonstrated a tendency to resist zoning laws and regulations that hamper their profits, and to look for loopholes and workarounds that can result in higher returns on their investments. The fact that skirting or getting an easement from zoning regulations can directly lead to floods and loss of the structures only means that there will be more business to be had in the rebuilding of the homes. Therefore, zoning decisions cannot be controlled or influenced by the construction industry!
Houston clearly cannot allow any further damage or encroachment of its precious retention lakes and bayous. City planners cannot permit developers to thwart or ignore zoning laws. This was starkly demonstrated during Hurricane Harvey, when communities that were built too close to the large retention lakes northwest of the city were submerged. Now, as Houston rebuilds, the priority is being placed on increasing the number of these critical artificial watersheds, augmenting and protecting the natural bayous, and on carving out stringent zoning regulations that are carved in granite.