Knoxville — Ah, beautiful June in Iowa. Come drive with me. See beautiful land and wide spreading lawns. See our towns and cities with well-trimmed lawns. See the expanse of low-mowed lawn around large suburban homes. And the activity! Retired farmers happily ride their lawnmowers over lawns, grader ditches, and everything but the corn field. Well-paid lawn keepers guide elegant little mowers to shear all the growing green at just the right height.
Meanwhile, we’ve read: “Floodwaters filling Saylorville like a tub” or “Storms put Iowans in saturated state.” And we’ve noticed that White Breast “Creek” and Teter “Creek” are now White Breast Lake and Teter Lake.
What’s wrong with this picture?
Is there a connection? Remember stories of the native people? They allowed grasses to grow five or six feet both above ground and below ground, and they did not even have a word for “flood” – they didn’t need it. Notice that in today’s fields where farmers want to protect the land, they have grassy strips called “waterways” so water can infiltrate rather than create gullies of fast-flowing rain water.
I know there’s a connection between lawns and floods. It should be obvious: Taller, healthier grass absorbs more water. In fact, I’ve read that a low-mowed lawn is second only to sheer concrete in the rate it sends water flowing down the grade. But I Googled and Googled to get a handy statistic – vast resources on watering your lawn, repairing your lawn after a flood, and floods in Oak Lawn and Fair Lawn – but nothing clear on growing lawns to hold water. Finally, one brave web site from Lake George, New York, put it in print: “Large lawns that extend to the lakefront increase … stormwater runoff from developed sites and uplands.”
Stormwater runoff increased by large lawns? Yes! And at new building sites water risk is increased: Top soil is removed and replaced with a thin layer while heavy equipment compacts the soil; grass roots can’t get in deep and the result is a “sheet flow” of water that doesn’t infiltrate the soil. Turf runoff with all its fertilizers, herbicides and pesticides flows on to help make floods.
And, Wow! Lake George recommendations for saving their lake from poisonous runoff would also help prevent floods: (1) Limit the size of a grass lawn. (2) Plant or maintain a stream buffer and a rain garden. (3) Mow the grass to a height of 3 inches or more … (4) Leave grass clippings on the lawn as a natural fertilizer. (5) Do not use fertilizers, herbicides or pesticides.
Following these guidelines would help immensely. If we simply took lawns back to their size before power mowers – at least before riding mowers – there would be less flood risk. And if golf courses were smart enough to promote a game played on grass an inch or two higher, they would become a healthy instead of a dangerous model. All the tiredly-perfect institutional lawns don’t help either.
Now that I’ve offended the lawn care companies, yard equipment makers, and many of my friends and neighbors, let me add: this is a big deal because USA lawn acreage is greater than Pennsylvania, Delaware, and Rhode Island combined.
If we could come even close to Lake George guidelines we’d have less flood danger in Iowa and we’d have cleaner, safer water, too. Maybe even make Iowa more competitive with Lake George in tourist attraction. You get the picture?