Science should be our guide on issues involving floodwaters

When my wife and I were house hunting 20 years ago, one thing we liked about our now-purchased house is that it is a few blocks away from the St. Marys River.

Our Realtor warned us, however, that she had to double check the floodplain maps to see whether we would have to purchase flood insurance. As it turns out, there is a convenient slope between our house and the river, so we are outside of the 1% and 0.2% annual floodplain risk.

Planning for a flood is important. Ever since that experience, I've paid a little more attention to flood-related news than I used to. Because of that experience, two flood-related news items caught my attention recently, one local and one statewide.

Locally, there has been a lot of discussion about the plan to build in a currently wooded area along Spy Run Extended. The area is especially low elevation, right by the St. Joseph River and next to the great bike path that connects downtown to those areas north of Coliseum Boulevard. I used to bike through there on my commute.

Among the many reasons to avoid developing this area is that it currently serves a purpose for all of us.

It floods frequently. I know because I would have to find another bike route when it was flooded. That flooding, in a sense, is good for us.

After a heavy rainfall, the water has to go somewhere. The least damaging route is for the water to soak into the soil and slowly flow through the soil into the river. By moving through the soil instead of over concrete, a couple days of heavy rainfall can be spread out before entering the river.

There was a study done by two scientists, at Columbia and UC Berkeley, that measured how valuable this process can be. They specifically measured how much a wetland area near a river can prevent flooding downstream. More precisely, they measured how much flooding increased when a wetland was converted and built on.

For each hectare of wetlands removed, there was increased flooding damage downstream worth $2,300 every year thereafter. This area near Spy Run Extension is between one and two hectares.

So in addition to the other objections to this development, we should consider the additional flooding damage that will result.

The second news item is at the state level. A bill was recently introduced in the Indiana Senate related to flooding.

Senate Bill 242, authored by Sen. Jean Leising, R-Oldenburg, proposes to change how the state regulates areas at high risk of flooding.

Under current law, local floodplain administrators have to use, these are actual words, the "best floodplain mapping data available." The bill, among other changes, would remove that requirement.

There are two common sources of predictions on flooding: the federal government (through the Federal Emergency Management Agency and the National Optical Astronomical Observatory) and the state government (through the Department of Natural Resources).

It appears that the state-level information is more up to date on recent rainfall increases. These updates will make it up to the federal level.

News reports indicate, however, there can be a delay of several years since federal agencies have to coordinate the update for all 50 states.

The proposed Senate bill would exploit this delay. The bill would require local floodplain administrators to use the less-accurate FEMA predictions.

The news stories I've read describe the debate over the bill as between people who think local floodplain administrators are too restrictive and people who want them to be more protective.

That's a pretty terrible way to think about this issue. A more useful way is that we can either use the best flood information or not the best. The current law requires using the best information. The proposed bill would eliminate that requirement.

The true justification for the bill is that some people don't want to face the true risk of flooding.

If you live in a high floor-risk area, the Senate bill will not help you. Requiring different construction or requiring flood insurance is dealing with nature. Changing the law only ignores the problem instead of dealing with it.

Christer Watson of Fort Wayne holds a doctorate in astronomy and writes about the applications of science on everyday life.