How municipal regulations and planning can help minimize flood catastrophes

single-meta-cal September 13, 2017

The recent hurricanes that struck Texas and Florida were reminders of the powerful force of Mother Nature and the crippling effect on cities and states. In this two-part series, City Blog looks at the challenge of flooding. Now: What the City has done proactively. Next: What you can do proactively.

Houston’s flooding in the aftermath of Hurricane Harvey was a lesson in being proactive and in its lack of strong legislation. And, frankly, the back-to-back blows of Harvey and Irma also served notice that sometimes a city is at the mercy of the weather, and the best hope is to minimize damage, loss of life and injury.

As Time Magazine recently noted, “experts say sea level rise and increased precipitation related to climate change could exacerbate the problem (of flooding and hurricanes) in the coming years.”

While Huntsville is well removed from immediate damage from hurricanes, it’s close enough to feel residual storms, as we’ve learned this week; with the proximity of the Tennessee River and with rain unrelated to hurricanes, there is potential for flooding here.

A “100-year flood” is not out of the question. That’s a confusing label, which actually means there is a 1-in-100 chance of a major flood in any given year.

Time reported Houston “allowed developers to build new communities with little regard for flooding projections,” a common sin among many growing cities. A “lack of zoning laws … encouraged extensive property development with little regard to the environmental impact and strain on infrastructure,” the magazine said.

Huntsville’s flood mitigation

Though some 13 percent of Huntsville’s developed property is within floodplains, the City established strict flood mitigation regulations in 1991 that have been constantly re-examined and updated.

Kathy Martin, Director of City Engineering, says that there “is an importance placed on our regulations and making sure we enforce them.”

All new commercial and residential development must have retaining areas or draining that can manage the flow of excess water, Martin says. Any building within the flood zones must be elevated or flood-proof. There is no building in a flood-way.

There is an importance placed on our regulations and making sure we enforce them.”

Developers are advised of potential flooding and must build accordingly. For instance, Martin says, homes in newer neighborhoods in south Huntsville with a proximity to the river and the feeder creeks must be a foot higher off the ground than standard. A yard might flood, but the house is safer from peril.

Public Works, Landscape Management and Engineering share the role in keeping waterways free of debris, though landowners must assume a role in clearing banks and ditches adjacent to their property.

From floodplain to greenspace

The City has taken a proactive step in transforming floodplain areas into greenspace. Land that couldn’t be adopted as commercial or residential can still serve residents as recreational areas for walking, hiking and biking.

According to Martin, most Huntsville residential draining systems are designed for a 10-year storm, meaning an event that has a 10 percent chance of happening each year. To design infrastructure to fully control a 100-year storm would not be feasible, because of size and expense.

Huntsville is a participant in a National Flood Insurance program through FEMA and also provides updates to residents whose homes are in floodplains.

The outcomes in Texas and Florida have proved that nothing is infallible in coping with the weather. But minimizing the peril through regulation and common sense could mean the difference between catastrophe and a simple nuisance.