From what little of it I am able to see from my front windows, the Mousam River’s surface is forever changing. Some mornings, it’s rough and choppy, and depending on which way the wind is blowing, it erupts into ripples that move every which way or sometimes not at all. And then on others, it’s calm and still as a mirror, reflecting the trees and buildings on the opposite shore so distinctly that it’s often impossible to discern where the land ends and the water begins.

The surface of the water in ponds, lakes, large streams and rivers is a pretty good indicator of how hard the wind happens to be blowing on any given day, and it’s safe to say that, the smoother it is, the less windy it is. Many years ago, my very young son did a project for a school science fair on how ocean waves form. I was taking an oceanography class in college at the time, so together, we replicated our own miniature sea in a rectangular plastic dish basin, which, along with the “wind,” he was able to produce by blowing on the water’s surface, was all that he needed to illustrate his chosen science fact. He designed and decorated a small poster to identify his project, and I will always remember how proud he was when fair visitors asked him to demonstrate the process.

When the river’s surface is calm, it’s easier to notice the disturbances created by birds, such as ducks, that glide along in the early morning stillness. I keep the field glasses close by for just such moments, and am often rewarded with a view of a pair of mallards exiting the water on the opposite shore. I have no idea what goes on along the near shore, as it drops down too steeply to allow me any sort of view, and it borders other properties whose tenants might not appreciate anyone trespassing in order to get a closer view of the river from that angle. So I often content myself with walking to the dams on both Bridge and Mill streets, where, while the water’s action is not accommodating to wildlife, I am able to witness its power as it cascades over the concrete slopes and overflows across surrounding rocky outcroppings.

The Mousam winds its way through some pretty tight quarters in places, thereby concentrating its energy in a smaller area, as compared to some rivers whose shores are farther apart. Looking at a map of the area illustrates how water-rich the entire Sanford-Springvale area is, and there is no shortage of vantage points from which to view it all. I have to keep reminding myself that each individual feature of this river is just a small part of a watershed draining land that spans 122 square miles, ranging from sections of Acton to parts of Kennebunk, where it eventually meets the sea at Parsons Beach. The river originates at Square Pond and Mousam Lake in Shapleigh and collects water from wetlands, ponds and streams before even reaching the Sanford area. When land cannot absorb rainwater for whatever reason, it is said to be impervious. Therefore, most storm water simply washes over it, adding significantly to the amounts that flow into rivers such as the Mousam, along whose Sanford banks exists a high percentage of this type of land surface. Think “water off a duck’s back,” and you get the idea.

Farther east, the river’s middle branch takes on water from Shaker Brook and other wet areas on its way through Alfred, where it rejoins the main branch of the river at Estes Lake. Water from both branches ultimately reunite there on their way through Kennebunk where it passes through a tidal estuary before emptying into the Gulf of Maine. A salt marsh that is part of the Rachel Carson Wildlife Refuge borders this end of the Mousam River, and together, they provide an important habitat for many species of waterfowl, including the piping plover.

It’s hard to imagine all of this when standing near the dam on Mill Street or looking down at the freshet that runs past the old Sanford Mill, hard to believe that this seemingly innocuous stream plays such an important role in the watershed ecology of a much larger geographical area. It’s just another example of how intricately woven all of nature’s processes and systems are, with rivers being a visible reminder of how all of life is connected and how each element depends upon all of the others for its own survival.

— Rachel Lovejoy, a freelance writer living in Springvale, who enjoys exploring the woods of southern Maine, can be reached via email at rachell1950@yahoo.com.