Skip to content

Don’t forget the other Big Dig

Boston’s central artery project, also known as the “Big Dig,” was the most complicated public works project in American history. We took Boston’s busiest highway and made it disappear along with its ramp system. For sheer bravado in engineering, nothing can match the Big Dig, right? Well, let’s turn back the clock about 200 years prior.

Big Dig before and after
The Big Dig, before and after.

The challenge

It’s 1790. We’ve just “unfriended” Britain, so we need to become self-sufficient, and fast. We need a strong economy to revolve around Boston. What resources do we have? We have valuable granite around Chelmsford. We have timber in New Hampshire. We have farm products like fruits, vegetables and ham all throughout the area. The big marketplace for this stuff is Boston, and overseas from there. In turn, Boston has really nice finished products to sell inland. And to transport these goods, we have the powerful Merrimack River. We’re all set!

But we’ve got a problem. The Merrimack doesn’t go to Boston. To unlock all this potential commerce, we need a way to transport heavy loads back and forth between the Merrimack River and Boston. That’s almost 30 miles. How on earth can we do that? Let’s go over the options:

  1. By plane? No such thing.
  2. By train? No such thing.
  3. By automobile? No such thing.
  4. By ox and cart? Too slow and inefficient. And the streets are unfit anyway.
  5. By boat? Mother Nature has already provided a network of rivers for us, but nothing straight from the Merrimack to Boston. Plus, some rivers are on much higher ground than others. And there are streets in the way. Forget it.

Unless we build our own river.

There’s a term for that. It’s a canal, a freight-moving solution that dates back to 4,000 BC in the Middle East. But this is New England. We have rocks, trees and winters. This would take a LOT of men and a LOT of shovels. Nothing is level around here. Boats would have to go up and down, not just across, so we would have to build locks, basically boat elevators, to raise or lower the boats from one section to another. And even locks wouldn’t solve every issue. We might have to build elevated waterways to carry our river OVER other rivers. If we’re going to make this happen, we’ll need one hell of an engineering team.

Calling all engineers! Anyone?


America had no engineers of this caliber. We had no engineering schools. And yet Gov. John Hancock signed a charter in 1793 to make this canal happen. Other big names signed on and invested money, including John Adams and John Quincy Adams — 50 shareholders in all. They finally appointed Loammi Baldwin, a Revolutionary War veteran and cabinet-maker from Woburn, as superintendent of the project. He had to make the Middlesex Canal real. Somehow.

The first step to any big construction project is surveying. This canal project would fail horribly if water flowed in unexpected directions or rushed too fast downhill. Nowadays, surveyors use a setup called a total station to determine relative height from one spot to another. 


Spectra Precision SPS720 Total Station


Superintendent Baldwin had no instruments. He asked a self-taught Woburn surveyor, Samuel Thompson, to tackle this with his crude gear. Well, just as the central artery project stumbled out of the gate (the Ted Williams tunnel came up almost four feet short at first), the Middlesex Canal stumbled also. Thompson didn’t know what he was doing. His survey said the Concord River was lower than the Merrimack, but it turned out to be almost 30 feet higher when someone else double-checked. Obviously Baldwin needed to find better talent. But where?

A reluctant Brit saves the day

Great Britain had canals and experienced surveyors, especially a whiz kid named William Weston Young. He had advanced equipment and knew how to use it. But a crew in Philadelphia had already snatched him to supervise two canals. So Baldwin called off the Middlesex Canal project, right? No, Baldwin was superintendent because of his good noggin. It was time to use it. He traveled to Philadelphia and tried to poach Weston by offering him more money. No dice. Weston would not budge. But Baldwin eventually found a weakness: Weston’s wife.

She was keen on Boston because it was more highbrow than Philly. She relished the Boston social scene. Baldwin wrote back to his Woburn team: “She observed that all the English Gentlemen and Ladies enjoyed themselves better in Boston than in any other place. I dare say that in my important business, you will think this is a very trifling circumstance to report to you. However, the only hope of securing Mr. Weston’s assistance rests on this circumstance.”

So the Woburn team managed to get Weston and wife to visit Boston for a few months over the vehement objections of the Philadelphia teams. While the Woburn team wined and dined Mrs. Weston in Boston, they also put Mr. Weston to work with his wye level, a prototype for today’s leveling equipment. It was the first American use of an accurate level.

Wye level

Finally, the Middlesex Canal had a target route, thanks to the scientific fact that Boston is more hip than Philly. Click the map below to explore the route. On the Boston end, the canal may appear to terminate in the middle of nowhere, but remember that Boston was a lot more watery in 1800. The canal is under today’s Rutherford Avenue. The boats snaked through downtown and reached a ship terminal where Quincy Market is today.Middlesex Canal map

Good morning, sir. We’ll need your land.

Now for the next headache: knocking on doors and telling the owners of 143 parcels that their properties were about to get a water feature, like it or not. Some landowners, most of them farmers, saw the benefit to the region and donated their land. The stubborn ones forced Baldwin and company to wave Hancock’s signature at them, an early use of “eminent domain” principles. Luckily, Baldwin had a carrot to offer the landowners, besides a few dollars up front. They could earn ongoing money by digging. The canal had to be 30 feet wide at the top, tapering to 20 feet at the bottom, and three and a half feet deep. Shovels broke ground in 1794.

Middlesex Canal Diagram

Here’s a section of the canal in Winchester. Note the raised embankments on both sides, just as the diagram shows. The “towpath” was an elevated walkway for work animals. They tugged the barges along the canal, using ropes, at about two miles per hour, the walking speed in the video.

Ready? Set? Hack!

It was sheer drudgery to hack away at knotty, rocky New England earth using crude little shovels made by the canal company at its own blacksmith shop in Billerica. Some laborers walked to work or boarded with abutters, while others lived in monitored barracks along the route. Every day except Sunday, the crews started hacking and yanking at sunrise and didn’t stop until sunset. During the dog days of summer, they were sometimes allowed a 90-minute break, but then they’d have to work until 20 minutes after sunset to make up for it.

Middlesex Canal shovelsWhat about existing rivers and streams? They were not beneficial at all. In fact, they could flood the canal, so the canal had to be carried over natural waterways using elongated troughs that functioned like amusement park water slides. Here are the stone abutments for an aqueduct in Wilmington near Route 38. Now picture a water basin extending perpendicular to that river, from one wall to the other.

Middlesex Canal Shawsheen River aqueduct site, Wilmington MA

And more abutments at the Shawsheen River along Route 129. Note the U-shape groove to accommodate the aqueduct, which ran across the top.

Shawsheen aqueduct
Shawsheen River aqueduct, Billerica, MA

Here it is in action. Note the clever footings built into the walls, to support the aqueduct’s legs.
Middlesex Canal Shawsheen River aqueduct illustration, Wilmington MA

At the much fatter Concord River in Billerica, Baldwin devised a floating towpath of logs for the horses to walk upon while tugging the vessels.

Floating towpath over the Concord River, Billerica

  • What about rocks and tree stumps? Teams of oxen yanked them out.
  • What about really big rocks and ledges? Dynamite didn’t exist yet, but simpler and weaker “black powder” did. Sometimes it ignited unexpectedly and caused injuries.
  • What about moving earth? Baldwin devised dump carts, primitive dump trucks that could tilt and unload.
  • What about swampy areas? They were a real pain. Crews had to dump lots of earth and gravel to form embankments, and then tamp it all down to make it dense and water-tight, and repeat this operation over and over. Load after load of horse-drawn carts traveled over muddy, soupy territory on wooden planks, dumped their loads, and went back for more. It was ugly and tedious work.
  • What about morale? With the completion of every phase, there was a huge party at the nearest tavern.
  • What about the boat elevators? How did Baldwin build stone chambers for raising and lowering boats without leaking any water? For the walls, he ordered expensive volcanic stone from the West Indies, mixed it with lime and sand, and made the first use of hydraulic cement in America. Just as the central artery project pioneered slurry walls, the Middlesex Canal pioneered good old cement.

Collateral damage

The Boston central artery project allegedly left a path of destruction to nearby homes. Cracked walls, flooded cellars, shifted foundations — all the fault of the Big Dig, say myriad plaintiffs. Similar complaints dogged the canal project and drove up costs due to the payouts. People blamed the canal for ruined drinking wells and flooded farmland. Also damaged was Newburyport. Huh? Yes, it was damaged economically because Merrimack River freight had traditionally gone to Newburyport, but now this dastardly Middlesex Canal diverted business to Boston.

Opening day at last

The plan was to fill the canal with water from the Concord River in Billerica because it was the highest-elevation spot along the route. Baldwin knew, thanks to that hard-won survey, that the water would flow slightly downhill in both directions from there. In December of 1800, the Concord was let into the canal. The water reached Wilmington in 1801 and Woburn in 1802. On the last day of 1803, the last link was opened to complete a water highway from the Merrimack River in Lowell to Mill Pond in Charlestown. It was open for business at last.

Despite the setbacks, the canal was finished before the 10-year deadline targeted by the charter. Imagine, a construction project actually finishing on time! But was it on budget? No, it was targeted for $333,000 but finished over $500,0000, so about 40% over budget. Not bad, considering the Big Dig finished 190% over budget — and nine years late.

And finally, the payoff

As soon as the canal opened in 1803, the disrupted farmers were rewarded. Property values along the canal surged. Everyone wanted easy access to the new water highway. A canal barge could haul 30 tons, 10 times more than a team of oxen. And those barges could go from the Merrimack to Boston Harbor in 12 hours, or 18 hours the other direction. That was impressive speed back then. Vessels were pulled, rowed, poled and sometimes sailed. A nice bonus: The connection to the Merrimack allowed water access all the way to Concord, New Hampshire. Soon logs were zipping down the canal from New Hampshire to Boston, and the value of New Hampshire timber surged accordingly. Starting around 1820, wares from Haymarket in Boston went up the canal to eager customers inland.

Boston architect Charles Bulfinch ordered granite from Chelmsford, Tyngsboro and Westford and used it for Mass General Hospital, the Middlesex County Jail in Cambridge, the state prison in Charlestown and University Hall at Harvard. Another architect, Alexander Parris, used Chelmsford granite for Quincy Market.

The canal had romantic appeal too. It was nice to ride a boat through the woods and then sit and have a picnic. Henry David Thoreau of Walden Pond fame wrote a tongue-in-cheek homage to the canal.

Maintaining the canal took some work. Rodents nibbled at the canal’s belly and threatened to drain it, so canal supervisors put a bounty on their heads. And winterizing was a pain. The locks needed to be drained every winter before water could freeze and expand. But the canal became a symbol of engineering wizardry and dogged determination. Engineers from the Erie Canal project in New York traveled to Massachusetts to get some tips. In 1808, the US treasury secretary called the Middlesex Canal “the greatest work of the kind which has been completed in the United States.”

Bounty on rodents, Middlesex Canal

It was a toll highway

Just like the Mass Pike, you took a ticket when you entered the canal. You presented it to agents along the route for signatures and finally gave it to the toll collector as you paid your toll. And just like the Mass Pike, the canal had speed limits — but not to protect people. They were all about protecting the precious canal walls. If you traveled from one toll station to another too quickly, you were “speeding.”

Speed limit sign

  • Rafts — 1 mph These usually carried wood to the Charlestown Navy Yard. Oxen provided the pulling power.
  • Scows — 2.5 mph These were towed by a single horse and carried fur, produce and coal down to Boston, and Boston’s retail goods back up the river.
  • Packet boats — 4 mph These carried passengers, the equivalent of buses. They were available to rent.

More rules: No traveling after dark, which meant 7 p.m. in the spring and fall, 9 p.m. in the summer and 10 p.m. on moonlit nights. Sunday travel was permitted, but no whistles could be blown to alert lock keepers of arriving boats, so they had to be alert all day. If you didn’t have money to pay tolls, the operators would put a lien on your merchandise, so they’d get a piece of the selling price. If you parked your load for too long without unloading it, you’d get slapped with a fee. Yes, a parking ticket!

Lowell is born

The enticing combination of the Merrimack River and the Middlesex Canal caught the attention of Waltham factory-owner Francis Cabot Lowell and his master mechanic, Paul Moody. This dynamic duo had just spurred the Industrial Revolution in 1814 with their water-powered textile factory on the Charles River in Waltham. The river moved a water wheel, which was hooked up to machines via a clever series of gears. Those machines cranked out the product, often clothing.

Lowell and Moody eyeballed the Merrimack River and saw dollar signs. It was much stronger than the Charles, and it had this new canal for finished goods. So in 1826, a chunk of East Chelmsford became an industrial town called Lowell. Ten years later, it was a city. By the mid 1800s, it was the biggest industrial complex in the country — thanks to the Middlesex Canal, the vital highway for Lowell’s products.

Waltham and Lowell are close siblings, so they share some names. Here’s the Lowell Mill on Moody Street in Waltham:

Lowell Mill on Moody Street, Waltham

And the Moody School in Lowell:

Moody School, Lowell MA

Short-lived glory days

Loammi Baldwin died in 1808, just a few years after the canal opened. He died blissfully unaware that the canal would die just 45 years later, killed by a newfangled thing called a locomotive, championed by his own sons. Yes, the rail boom of the early 1800s, which began in Quincy with a tiny granite operation, spelled doom for the Middlesex Canal — just as the canal was finally profitable and paying dividends to shareholders. Rail engineers, including Loammi Baldwin’s sons James and George, had cleverly used the old canal survey maps to lay down a rail bed nearby, and even used the canal to move equipment to build the railroad. In fact, an early locomotive called the Stevenson, imported from England in pieces, made its way up the canal from Boston to Lowell one section at a time, to be assembled and begin service. With freight moving off water and onto rails, the canal company lowered prices and bought newspaper ads to stoke demand. Here’s an ad from 1843.

Middlesex Canal ad

Nevertheless, in the 1850s, the Middlesex Canal business dried up. The company tried reinventing itself as a supplier of clean New Hampshire drinking water, but it didn’t fly.


Boston’s Big Dig killed people. John Hegerty, a piledriver, took a head shot from a 30-foot wooden beam in 1998. Fook Kan, a carpenter, fell 50 feet to his death in 1999. Laborer Frank Shea Jr. was killed in 2000 when a Post Office truck pinned him against a concrete barrier. Crane operator Lonnie Avant was crushed in 2003 when the 65-ton vehicle swiveled to one side, pinning him between the cab and the wheel treads. And Milena Del Valle was crushed in 2006 when concrete ceiling panels fell on her car.

The canal killed people too, but not due to construction mishaps or engineering failures. It killed because it contained water.

Middlesex Canal drowning in Charlestown
Washburn Jewell drowning Middlesex Canal

And finally, horribly, the drowning of little Charles Baldwin, the grandson of Loammi Baldwin. Yes, the superintendent of the canal, the man considered the father of civil engineering in America, lost his own grandson to the canal.

Charles Baldwin obit 1811

The canal today

You don’t have to venture deep into the woods to find the canal. It hides in plain sight, often disguised as a natural stream. Surely you’ve seen this impressive structure on the corner of Main Street and Alfred Street in Woburn:

That’s Loammi Baldwin’s house, with the canal at its feet. The house was originally across the street near the current Stop & Shop plaza, but was moved during the expansion of that shopping center. If the Baldwin name rings a bell in Wilmington, it’s because of the Baldwin Apple monument on Chestnut Street. While surveying for the canal, Baldwin discovered distinctively tasty apples on the property of William Butters, and propagated them into a successful business venture. A harsh winter in 1934 destroyed almost all Baldwin apple trees, so they’re hard to find today.

Baldwin House move, Woburn MA
Baldwin House move, Woburn MA

On Faulkner Street in Billerica, you’ll find the Middlesex Canal Museum & Visitors Center and the Faulkner/Talbot mills along the Concord River. This is where Baldwin built that impressive floating towpath you saw earlier, so barges could traverse the river before the drop.

Talbot Mills, Billerica MA


And that’s also where you can see the only intact lock from the canal. Yes, still there!

Middlesex Canal lock, Billerica, MA

This video of another old canal surely parallels the Middlesex Canal:


Some historians consider the Middlesex Canal the first American highway. Others call it the first internet. But most people have no idea it existed at all, even though we’re surrounded by its remnants and rewarded by its industrial legacy. We should proudly marvel at both of our Big Digs.


Editor’s note: If you’re reading this article on a cell phone, it might not display properly. Scroll to the very bottom of your screen and tap “exit mobile version.”


9 thoughts on “Don’t forget the other Big Dig Leave a comment

  1. A great job; comprehensive, good tenor and a clear report on a long-noticed but not studied phenomenon.

  2. Great, well told story about our past. I’d no idea that a canal existed in “metro west” Boston. Thanks!

    • Excellent story. I was aware of the canal in Woburn and Winchester and also knew some facts about Baldwin but your story and facts really enlighten me. Thanks.

  3. Interesting story.
    When I read the title, I thought this was going to be about Burlington’s sewer project.

  4. Great job Robert. Traveled all around this canal in my younger days and didn’t really recognize its existence or its importance in our local history. Thanks.

  5. Great read! I’ve known about the Middlesex canal for some time and seen some of its remnants, but never new that much history about it. Thank you for the history lesson!

  6. Thanks for a comprehensive and concise summary of the canal’s history and its place in the context of our local cultural, technological and commercial histories!

Leave a Reply