Mike Kline, state rivers program coordinator for the Vermont Department of Environmental Conservation, examines a section of the Winooski River in Middlesex. Kline uses historical documents and other evidence to determine where rivers have been artificially straightened. Photo by Mark Bushnell
(“Then Again” is Mark Bushnell’s column about Vermont history.)
[I]f you want to understand how Vermont’s rivers should flow, ask a historian. Or better yet, ask a scientist who also uses the tools of a historian. That’s what the Agency of Natural Resources has been doing for more than a decade.
The goal is to determine how best to manage the state’s rivers. “The prize is great if we can get there,” says Mike Kline, state rivers program coordinator for the Vermont Department of Environmental Conservation. “We’ll see less flood erosion, less flood damage, less pollution into the lake, better fish and plant habitat. We will get all these things we value — and chief among them is public safety in a flood.”
The kicker is that careful management will cost less money in the long run.
Scientists began dabbling in history because “we were trying to understand what was causing the instability of our current rivers,” says Kline.
Note that term: “current rivers.” Though we can only witness a river’s present-day form, Kline says that to understand how a river will change in the future, scientists know it helps to look at how it was in the past.
Agency and consulting scientists are now using various types of historical information to piece together a river’s past, primarily by relying on old maps and photographs, as well as local memories.
Aerial photographs, which date back to the 1930s and earlier, are valuable resources, Kline says, because they show precisely where a river flowed at a particular time. If you want to study an earlier period, you can look at old topographical maps, or if you want to delve as far back as the mid-1800s, you can study the Beers Atlas of Vermont, which was produced starting in the late 1860s.
Rivers will have their way
Once, while examining an old topographical map of the town of Stockbridge, in the central part of the state, Kline noticed something odd: The river ran parallel to the base of a hillside. “Why is the Tweed River hard to the toe of the valley?” he asked himself. That’s not where it would naturally flow. The reason for that is complicated, but to put it simply, water flows in a corkscrew motion, so it won’t go in a straight line for any significant distance. Instead, it will meander in a serpentine fashion.
Kline also noticed a railroad spur on the map that ran beside the river and led to a copper mine in the Michigan Valley near Pittsfield.
“My guess,” he says, “is that landowners negotiated with the railroad to move the river next to the tracks as a condition for using their land.”
Kline understands the landowners’ motivation. Rivers naturally shift over time, which is a nuisance to abutting farmers. The landowners may have thought, Kline says, “If I can get (the railroad) to put their infrastructure next to the river, it will be their headache.” And railroad executives probably agreed to move the river and assume responsibility for its course, because they figured they would have to manage the river anyway and this way also got them permission to use the land, he says.
Kline wonders how much of a role railroads played in reshaping the state’s rivers. Ultimately, however, rivers usually rebel against this kind of reshaping. The railroad’s bet that it could contain the Tweed River proved to be a bad one. That spur has been gone since floodwaters obliterated it in the early 20th century.
The problem, Kline says, is that a river can be contained within a lengthy, narrow channel for only so long. Eventually — it could take 80 or 100 years — a river will dictate where it wants to flow; a chink will develop in the riverbank, and the water will fight its way through.
Around the state, you can see these manmade straightened stretches of river that inevitably burst out into wide areas that regularly flood, particularly in major storms like Tropical Storm Irene, which struck Vermont five years ago.
While Kline can glean important information from a 150-year old atlas, he prefers more modern resources. “You can’t trust maps as much as photographs,” he says, “because they rely on hand-drawn interpretations of what is being seen.” Topographical maps are more accurate than Beers maps, he says, and photographs are the most accurate of all.
Kline is particularly fond of the University of Vermont’s Landscape Change Program website, which features historical photographs of the state. Many of the images show rivers. Since the website also includes the location where the photos were taken, scientists can visit the scene to compare the historical location of the river to the current one.
Joining memory with science
When working with a community, Kline wants to hear what residents know about their river’s history.
“When you combine the science with their experience,” he says, “there is going to be a fit there. If there is an oral history or memories of the river and you can put events in the proper sequential order, it suddenly makes sense with the science.”
Kline says local residents can provide invaluable details about what has been done to the river over the years, such as straightening its course and reinforcing its banks in hopes of preventing flooding.
Vermonters have long sought to re-engineer the state’s rivers. The region was once a place of forested swamps, Kline says, but then people cleared the land and it dried out. Vermonters considered dry land the only good land. Kline cites old Vermont statutes that made it the responsibility of property owners to drain their land. In fact, property owners could get permission from their local selectboard to go onto their neighbors’ land to drain it if the neighbors wouldn’t do so themselves.
“The theory was that everybody had to be pulling the plug or the system wouldn’t work,” says Kline.
Vermonters had the mind-set that they had to instill order on the natural world.
They were hardly alone. The headline on a 1935 advertisement for the DuPont chemical company read: “How DYNAMITE streamlines streams.” The reason streams needed “streamlining,” the ad argued, was that “(c)rooked streams are a menace to life and crops.” River bends tend to move over time, causing flooding. If a river could be put into a channel and forced to stay there, the thinking went, then floods could be minimized.
That sort of re-engineering work is still visible in the landscape today.
“We’ll often go out to a river and see that the river is straighter than it naturally would be,” Kline says. However, he notes: “Rivers don’t flow straight for that long naturally.”
The laws of physics dictate that a river will choose the least erosive path, Kline says, which tends to be a winding one. Straightening a waterway will likely lead to relatively sudden changes in its course later as it tries to return to that least erosive path.
That’s the situation Kline and fellow river scientists found a few years ago when they visited the Trout River in Montgomery. The river, which had been forced into several long, straight sections, had been changing course regularly and causing trouble for abutting landowners. By studying the river’s history, Kline found that it had previously been a naturally meandering river, with plenty of oxbows. The river was merely reverting to its natural self.
And here is where history can help inform future planning. By overlaying aerial photos of the river from various periods, scientists can show towns and local landowners where the river has naturally flowed — and flooded — during different periods. That gives a pretty good idea of where not to build.
In areas like villages, however, we might have no choice but to leave a river that has been forcibly straightened, because buildings have been constructed along its banks. Upstream and down from villages, though, we would be better off letting rivers take their natural courses, Kline says. They might occasionally spill over, but that would have the effect of releasing their flood energies, thereby protecting the more-developed area in the village.
Once you explain to people the science of the river and show how it connects with history — whether oral history, land records or physical evidence, like maps and photos — Kline says, “they understand what the history of that conflict has cost and how their role in that might have an effect on other people. They tend to begin listening and become appreciative of that fact-based science.”
Read the story on VTDigger here: Then Again: History informs views on rivers' future courses.
