Anyone who has driven a car or ridden a bike around Gouldsboro and Winter Harbor knows that the Schoodic Peninsula is hilly. Riding or hiking on the hills down the peninsula’s spine, it is not unusual to drop from hundreds of feet down to sea level over a half-mile or less. Those rapid elevation changes can turn a rainfall event into a mighty, destructive torrent, as we saw last June. Climate models predict that, over the coming years, Gouldsboro will experience intense rainfall events with increasing frequency. So, it makes good sense to develop a better understanding of how and where all that water is likely to concentrate.
Because of the peninsula’s violent geologic history, the hills here are not rounded and smooth but creased with folds and valleys that concentrate water into a surprisingly complex system of watersheds. The picture at the top of this post shows Gouldsboro’s primary watersheds, making it clear that predicting where all the water will move when we have an intense rainfall event is complicated. It is even more complex than the picture suggests because each primary watershed consists of smaller “sub-watersheds” that can, on a local level, result in significant flooding and damage. On the left is a picture of me looking underneath Rt. 186 at what used to be a solid roadbed suddenly transformed into a cave with nothing much holding up the road. I will tell you more about this example because it helps explain why the town needs everyone’s help to identify potential trouble spots.
How a Little Stream Can Suddenly Get Big
The aerial view on the right traces the stream that did the damage in the picture above. Most days, it is a quiet little stream carrying just a few inches of water. Notice that, according to U.S. Geological Survey’s map, the stream is a short little thing that begins just on the other side of the road. That distance is less than 150 feet. Looking back at the picture of the stream’s damage, it is natural to wonder, “How can such a little stream develop that much force?”
Answering that question requires thinking in terms of watersheds rather than streams. Fortunately, the U.S. Geological Survey provides an online tool that identifies the boundaries of the sub-watersheds, of “basins,” that drain into points along streams, even tiny ones, all across the U.S. The map on the left shows the sub-watershed that feeds this particular stream. Amazingly (to me, anyway), this little stream drains water from an area that includes the parking lots at Peninsula School and the town office and the uplands stretching south along Rt. 186. With this map, it was no longer a mystery how the storm last June could turn this small stream into a torrent. My rain gauge recorded more than 6 inches of rain in less than an hour in our backyard that day. Six inches of water spread over the entire yellow area on that map is a lot of water!
What This Has to Do With You
The town has a pretty good idea of how things used to be. Jim McLean, Gouldsboro’s Supervisor of Town Infrastructure and Road Commissioner, knows about the areas that have always flooded, the culverts that always back up because they are too small, and so on. But things are changing. We are getting more intense storms and rainfall coming at different times of the year, tending to bunch up in the fall, with generally drier summers. As the stream by my house shows, Gouldsboro is not just a few large watersheds but consists of hundreds of small streams and watersheds. Some of them handle the changes just fine, others not so much. The folks living around all the streams, ponds, vernal pools, and marshes in Gouldsboro will see the changes first. The town depends on all those people to share what they have noticed.
This Gouldsboro Shore program is at the center of Gouldsboro’s effort to collect this information. So, we have created a form to make it easy for anyone to quickly give us a heads up about flooding, new erosion problems, and problems you have noticed. Here is how you get to that form. It will take just a couple of minutes to fill out the form. Once we hear from you, we will follow up to learn more about the problem.
Tides Too!
I have focused this post on rainfall and floods. But water comes at Gouldsboro from below as well as above. We are also interested in hearing about flooding that people are noticing when we have especially high tides. We’ve published another post that says more about how sea-level rise will result in water in new places in Gouldsboro.
— End —
