Marvin D. Adams Waterway, A Short History

The west end of the Key Largo Cut going into Blackwater Sound – Photos ©Jacob Katel. All rights reserved

Salty sea dogs call it The Cut, and it’s been saving Key Largo boaters tons of time and gas since 1963.

The Marvin D. Adams Waterway is a man-made shortcut that was excised out of Key Largo’s bedrock for a channel between the east and west coasts of the island.

Like a half mile recreational Panama Canal, it chops through the core of Key Largo to create a boat route from the ocean to the bay that saves from costly travel around the whole island.

The Cut was blasted out of Key Largo Limestone with dynamite and surgically trenched with patented heavy metal machinery thanks to one man’s vision for boat crossing from his front door to his back porch; the Gulf of Mexico one side and the Atlantic Ocean the other.

That man was Marvin D. Adams, and he didn’t name the waterway after himself. Mayor Harry Harris named it so by official proclamation in 1976.

The Key Largo Cut connects Blackwater Sound to Largo Sound, and saves roughly 25 miles of round trip travel.

Key Largo is the longest key in the Florida Keys island chain. According to John Pennekamp in a 1976 article he wrote for the Miami Herald, “The channel cuts across the middle of the Key at its narrowest place, one half a mile.”

©Miami Herald via Miami-Dade Library Collection

Marvin D. Adams and Pennekamp were old pals. It’s only fitting that Adams Waterway leads east into John Pennekamp Coral Reef State Park. Pennekamp was the Associate Editor of the Miami Herald, which shows that Adams had some high powered friends.

The Key Largo Waterway, as it was once known, is a great feat of engineering, and a monument to human ingenuity for the sake of convenience. It has benefited the Florida Keys boating community tremendously since it was finished in 1963.

For one thing, in the case of fast moving hurricanes, it offers ocean side boaters a faster way to move into more protected waters on the Florida Bay side of Key Largo.

©Miami Herald via Miami-Dade Library Collection

Marvin D. Adams moved to Florida in the 1920s and ended up growing into a major insurance guy and real estate pro. That’s where he made his bank. Then he opened an actual bank association, First Federal Savings and Loan, and had many other business ventures. He was involved in the community through civic organizations and was also head of the Florida Turnpike Authority in the early 1950s, contentious years of highway building in American history.

All of these experiences, plus being a rich landowner in Key Largo, helped him negotiate with all of the local, state, and federal agencies including with a U.S. Navy Admiral; and also private telephone and electric companies, to chop out that big old chunk of ancient coral rock, build a bridge, reroute traffic, and move THE water pipe for all of the drinking water in the Florida Keys.

Somehow, he got it all approved, but the deal almost fell apart when he priced it out at close to $700,000 to do the dirty work of cutting the channel.

That’s when a lucky meeting with D.G. Walton, a private contractor, saved the project. Walton agreed to do the job for free if he could keep all the rubble, which he made a boatload of money selling off as fill to other guys in the construction business.

According to a May 25th, 1976 article by Miami Herald Staff Writer Louise Montgomery, “D.G. Walton and Arthur Vining Davis had just completed developing a strip of Eleuthera, a Bahamian island. For that work, they’d built a special machine that, they said, “Cut coral rock, like it was cheese.”

©Miami Herald via Miami-Dade Library Collection

If you look today, the walls of the channel are still perfectly flat, with razor sharp lines that open a portal into the history of this fossilized coral rock formation, as if a hot steel crosscut saw blade spun through the bones of the Earth from the top of the rock ridge to thirty feet below the drink.

Maybe in a future article I will go deeper into this very interesting part of the story, which involves patented machinery.

Suffice to say through a variety of impressive means of negotiation, this Florida pioneer cut through all the red tape to make it happen to the point where cutting through forty five feet of limestone (fifteen above and around thirty below sea level) looks like the easy part.

And for all this ingenuity, we thank and remember Marvin D. Adams for the Marvin D. Adams Waterway.

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