John Lorson, District Technician
In a column earlier this month I wrote about the simple, yet important task of doing a walk-around of the outside of your home while rain is falling to ensure that your gutters and downspouts are working properly. Unfortunately, sometimes even the most carefully maintained and perfectly operating systems aren’t quite good enough.
Most of the newer homes in our area have gutter and downspout systems that are wonderfully built in terms of handling a typical rainfall. Professional installers consider the size, material and pitch of a roof then, calculate the size and slope of the gutter needed along with the number and location of downspouts. Finally, they determine the size of outlets needed to carry the flow to the nearest curb, ditch or stream.
The best of these contractors will use a set of standard calculations, tuned to the average rainfall patterns of the specific geographic area in which they are working, to ensure that the gutter system can handle what’s known in meteorological circles as a “10-year storm.” That’s a rainfall event of such intensity and duration that, over a long period of time (decades or even centuries), the average time between events of equal or greater magnitude is 10 years. The trouble is, we’re seeing storms of this intensity (and larger) more and more frequently—and some of our recent localized rainfalls have been off the charts!
A few weeks back, I got a call from a homeowner who was experiencing flooding in her basement and asked that I come and take a look at the situation and then, hopefully, offer a solution. The home was situated on gently sloping ground bordered on three sides by crop fields. When I arrived, the homeowners told me that in all the 30 years they had been there, they’d never had a flooding issue.
“Now, we’ve been flooded twice in just the past three years!” she said. “How could this be happening? Nothing has changed!”
I explained just what I’ve described above. The intensity of our storms (begin italic) has (end italic) changed. That change has been tracked and the data proves it out. (begin italic) A much greater than normal portion of total annual precipitation has come from extreme, single-day precipitation events. (end italic) (Source NOAA, 2016) (begin italic) Six of the top 10 historical floods in our region have occurred since 2003! (end italic) (Dr. John Peck, University of Akron, 2019)
The woman of the house wasn’t necessarily buying what I had to say. Her husband, however, seemed more receptive to the idea. When I asked if he had a rain gauge on the property, he led me to the garden where we both stood in amazement. The storm, which had encompassed all of three hours, had yielded 4.5 inches of rainfall! To put that in visual terms, that’s enough rainfall on their acre and a half property to fill 36,000 5-gallon buckets! That’s an enormous amount of rain, and a gutter and downspout system sized for the typical storm can do little to move that much water away from the house.
In the end, I made some recommendations for adjustments they could make to improve their lot before the next gully-washer. I’d be happy to do the same for you. Give me a call at Holmes SWCD 330-674-2811.
John Lorson, District Technician
John came to Holmes SWCD after leaving a career in higher education quite literally for greener pastures. He holds a BS in Biology from The University of Akron where he later worked for ten years—most recently as coordinator of the The University of Akron Millersburg Campus. Prior to that he spent 15 years as an engineering technician with the City of Orrville, dealing with storm water, infrastructure and planning issues. John can assist with conservation planning for your farm, rural property or woodlot. He also deals with storm water management issues, and investigates pollution complaints. Reach John with your conservation concerns at 330-674-2811 or email firstname.lastname@example.org