S.T.

December 25 🎄, 2022 By Mark Bushnell


If covered bridges didn’t already exist, the Vermont tourism industry would have to invent them . What more quintessential winter image can you create of Vermont, especially around the holidays? All you need is snow and a covered bridge, and you’re done. 

But don’t judge a bridge by its cover. Covered bridges might appear antiquated in the extreme, as if their sole remaining purpose is to be quaint, but in fact they are one of those rare innovations that even after centuries still perfectly fits its original purpose. That’s because covered bridges weren’t designed to be quaint; their quaintness was a byproduct of good design.

Some people have the misconception that the purpose of a roof on a bridge is to keep snow off it so it doesn’t have to be plowed. That was actually an unfortunate consequence of the design, but we’ll get to that in a moment.

The roof had — and still has — two purposes. The main purpose is to protect the deck and the trusses (the triangular sections that use a combination of tension and compression to support the bridge) from the elements.

While wood is a comparatively light, cheap and strong building material, moisture is the death of wooden structures. An uncovered wooden bridge might last only a decade or two before succumbing to rot. In contrast, a covered bridge can easily last more than a century. (A shout-out here to the Pump Mill Bridge, located on the Middlebury-Weybridge town line, which recently began its third century of service, making it the state’s oldest.)

Covering a bridge also offers a second structural benefit: The roof actually reinforces the truss, allowing for construction of longer bridges.

The Permanent Bridge

In early Vermont, when water 💧 power was king, communities naturally grew up beside a river, brook or stream. Build a mill by some dependably running water and you had a power source to make almost anything.

Bridges soon followed the mills, because they allowed towns to grow on both sides of the waterway. These bridges did away with isolation, and eliminated the need either to establish a ferry service or take a time-consuming detour.

When a community could afford to, it covered its bridges. The increased longevity was a good investment. Timothy Palmer, designer of America’s first covered bridge, believed that keeping the supporting trusses dry would add 40 years to a bridge’s lifespan.

Palmer’s original covered bridge was constructed in Philadelphia and dubbed the Permanent Bridge. Opening in 1805, the bridge spanned 500 feet, with a nearly 195-foot-long center section.

Palmer, however, underestimated the added life a roof could bring to a bridge. His Permanent Bridge operated for 70 years and was probably structurally sound enough to last for decades more. Its end came not by rot, but by fire.

A series of bridges spanning the Connecticut River between Windsor, Vermont, and Cornish, New Hampshire, faced similar challenges, though not from fire but from rising water.

The first bridge was constructed in 1795 by the Cornish man who ran the local ferry service across the river. He apparently decided that collecting tolls from the comfort of his home, which sat on the New Hampshire end of the bridge, was preferable to ferrying paying customers in all weather.

The structure, a simple, wooden bridge, was wiped out by a spring flood in 1824. Its replacement went up that same year, but like the first was destroyed in a flood. The third bridge on the site met a slightly different fate in 1866. This time the water came in the form of ice, which lifted the span off the abutments and sent it rushing downriver, where it smashed against a railroad bridge. The impact knocked nearly 400 feet of the lower bridge loose.

Ten hours later, the largely intact railroad bridge was seen floating past Brattleboro, which was roughly 50 miles downstream.

This was an important crossing, so construction of the fourth Cornish-Windsor bridge started that same year. Remarkably, the bridge company entrusted the same two builders who had constructed the third bridge to build the fourth. Not surprisingly, they altered the design, including raising it higher above the river.

Confident that this fourth bridge would last long enough to rot if not covered, the builders added a roof to it. Their confidence was well placed; the span — at 450 feet, the longest covered wooden bridge in America — is still in operation today.


The Cornish-Windsor Bridge stretches 450 feet across the Connecticut River, making it the country's longest wooden covered bridge. Pieces of the span were laid out in a field in Windsor by builders James Tasker and Bela Fisher before they connected them over the river. The lattice truss arrangement that underpins the bridge was originally patented in 1820. Photo from Wikimedia Commons

AGelbert NOTE: In order to fit this forum format, I had to position the following graphics differently than in the article. I replaced phrases "At left", "At top right", and "At top right" with "above" to describe the location of the following graphics.

Above, the diminutive Braley Bridge in East Randolph, sometimes called the Johnson or Upper Blaisdell Bridge, is less than 40 feet long.

Above, the Slaughter House Bridge, built circa 1872, is in Northfield Falls.

Above, a winding, snow-covered road leads up to the Mosely Bridge, which is sometimes referred to as the Stony Brook Bridge for the stream it crosses in Northfield. Photos courtesy of John H. Knox. For a gallery of Vermont landscape photos by John H. Knox, click here.

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Not just a bridge

Though a community could justify a covered bridge’s expense on purely practical grounds, the structures served other functions, as Vermont author Ed Barna noted in his 1996 book “Covered Bridges of Vermont.”

When not being crossed, the spans could function as large, albeit rather airy, public buildings. As such, they were sometimes used for church suppers, political rallies and meetings of the local militia.

They were also convenient spots for travelers to get out of the weather, for children to play, and for companies to post advertisements for their products. Ads for horse medicines were, predictably, a common sight on bridge walls.

Courting couples out on a walk or drive also knew the value of a covered bridge, as it offered them the chance to share a secret kiss (hence the term “kissing bridges”).

For all their benefits, covered bridges came with a unique maintenance cost. Each winter, the town had to pay for “snowing the bridge.” Think of it as the opposite of plowing. Before the advent of automobiles, people relied largely on horse-drawn wagons for transport. When it snowed, they switched out their wagons for sleighs, which could ride atop the snow instead of digging into it.

At this point, however, covered bridges’ ability to keep snow off the decking proved a liability. Sleighs need snow to glide upon, so towns hired a local resident each year to keep the bridge deck covered in snow.

The number of covered bridges in Vermont peaked in the late 1800s at somewhere between 700 and 800. There is no official count. The number has declined significantly since. A 1941 issue of the Vermonter magazine noted that the state then had roughly 160 covered bridges. That figure would have been significantly higher if not for the Flood of 1927, which destroyed an estimated 200 covered bridges. 

About 100 covered bridges remain

Today, Vermont has roughly 100 covered bridges. And they remain vulnerable to severe weather. More than a dozen were damaged in 2011 by Tropical Storm Irene, which swept away the Bartonsville Covered Bridge in Rockingham. A community effort led to construction of a new covered bridge in the same spot a year and a half later. 

As covered bridges disappeared, people started romanticizing them. “Covered bridging” has become a verb, much as “leaf peeping” has.

Through no fault of their own, covered bridges have inspired their share of saccharine artwork, as well as hyperbole. Take for example C. Ernest Walker’s writing in his 1959 book “Covered Bridge Ramblings in New England”: “Throughout our nation the robed figure of Liberty has been accepted as the emblem of Freedom, and the solidly framed covered bridge might well be selected as the symbol of its integrity.”

It is easy to make fun of how covered bridges have been depicted over the years in sepia-tinted photos and purple prose. They remain not only a testament to Vermont’s past, but also a practical gift to its present.

https://vtdigger.org/2022/12/25/then-again-news-flash-covered-bridges-werent-designed-to-be-quaint/