If you want to see folks get fired up, start a conversation over flood zones with a developer who wants to build in one or a homeowner whose possessions have been washed downstream. That scene played out yet again in North Carolina after the devastating flooding from Helene.

Many developers, realtors and floodplain property speculators wish flood zone regulations were less stringent. By contrast, emergency managers and community planners don’t think limits are strict enough to prevent catastrophic flooding damage.

Like so much environmental oversight, the issue is wrought with both poor understanding and today’s wild misinformation. With that in mind, let’s look at some history and explanations.

The National Flood Insurance Act was passed by Congress in 1968, in recognition of the difficulty property owners were experiencing in securing private insurance for floods. The related insurance program was intended to protect property owners at greatest risk of flood damage, but also reduce future flood damage.

When floodplains experience serious flooding, many ask why communities grew in such high-risk places. It turns out that early settlement along rivers had notable benefits. River valleys presented naturally easier pathways for travel.

Abundant water provided not only drinking water, but water for industry. Once upon a time, it was also a cheap way to get rid of the polluted water those industries produced. Pittsburgh, Johnstown and a host of Pennsylvania steel and paper mill communities were perfect examples of such places.

Water which runs downhill into these lowlands is problem enough, but we magnified the problem by paving and building on what became the surrounding suburbs. Locally, this included filling in wetlands for development (as happened along Plank Road) and piped and otherwise constrained urban creeks (as we did with Brush Run between Valley View and Pleasant Valley boulevards).

Scientists and engineers have now come to better understand the dynamics of flooding and how features like wetlands and man-made retention areas slow runoff and reduce flooding. Laws have changed to reflect these lessons.

The building industry has often complained that strict standards undermine profitability. This became a concern in North Carolina, where new home construction had been booming. The North Carolina legislature’s weakening of building codes in the last decade likely magnified the flood damage, according to a New York Times report.

Ironically, most of the FEMA regulations came to be because of the high cost of flood recovery to individuals, insurance companies and the federal government.

It’s only gotten worse since FEMA’s first regulations. Warmer oceans provide much more precipitable water. And if upper winds driving the weather causes that very moist air mass to stall (as Helene did in North Carolina), the rainfall amounts can be staggering. Accuweather’s computations put the figure at 42 trillion gallons of rainfall and the damage tally at $225 billion.

Yet one more factor contributed to western North Carolina’s nightmare. Both prior experience and FEMA’s risk maps could not reflect the magnitude of the event.

Already taking criticism from a wide variety of anti-regulation interests, FEMA was walking a regulatory tightrope even before climate change became a greater concern.

“These strategies to protect us from flooding are based in the past,” Anna Weber, a senior policy analyst at the Natural Resources Defense Council says. “All these systems that we rely on in our everyday lives were created for a climate that no longer exists.”

John Frederick (www.johnjfrederick.com) writes about science and the environment twice a month for the Mirror.