Terry Grantz stood on a swaying dock, pointing to a massive, off-white concrete block. He’s the manager of Lockwall One Marina, a private facility in the Strip District below the Cork Factory Lofts.
“When you come down into the area, you can see from the water, you can see the original wall,” Grantz said, gesturing to the submerged block. It looks old, but solid.
Grantz said he learned most of the history of the site from local anecdotes and a few pieces of paper posted on the gates outside the entrance of the marina: an article about Herr’s Island Lock and Dam.
But kayakers and other boaters may never have heard of Herr’s Island or the lock system that used to buzz beneath 23rd Street. Even Allegheny River boating maps leave something out: Lock and Dam No. 1.
From Downtown to the Point, where the Allegheny feeds into the Ohio, there isn’t a lock or dam system for nearly 10 miles.
But it wasn’t always this way.
Grantz said locks were originally constructed on Pittsburgh's three rivers to make them more navigable.
“They were just shallow creeks that were only kind of passable by boats in the flooding and spring seasons,” he said.
Locks and dams were designed to work like water steps through the region’s hills, valleys and varying elevations, making shipping and river commerce possible.
Boats go into a closed-off pool, where they sit while gates shut to stop water from flowing in. Then, depending whether they’re traveling upstream or down, the water level rises or falls to make it easier for the boat to continue on its route.
Steve Stolz, engineering manager with the Pittsburgh District Army Corps of Engineers, said the western Pennsylvania lock and dam systems are the oldest in the national Corps.
“They all have unique features,” Stolz said. “From over 100-some years old, there’s a lot of different engineering, a lot of different materials and a lot of the older ones are the ones we have the most challenges with.”
He said a lot of the locks and dams lack consistency because engineers were constantly experimenting with the mechanics. Builders used timber, brick, steel and concrete to create locks of all shapes and sizes.
Stolz said when Allegheny River Lock and Dam No. 1 was built, operating it would have been life-threatening. Men had to stand on steamboats and manually open and close the gates.
“It was very dangerous and very unsafe,” Stolz said. “Even during construction, there were no real hard hats [or] life vests.”
It took several years to complete construction on Allegheny River Lock and Dam No. 1. Workers kept running into problems, Grantz said, mostly natural disasters.
“Floods, I guess a tornado came through—yeah, of all things in Pittsburgh, a tornado—came through and destroyed a lot of what they were working on,” Grantz said.
When it finally opened in 1903, it was only the second concrete lock and dam the Army Corps had ever built. Transport flowed through for a few decades as the first step for Pittsburgh-area boaters traveling up the Allegheny.
Then, in 1919, construction began on the Emsworth Locks and Dam on the Ohio River. It was built with the latest and, at the time most effective, technology, like easily movable gates, more sturdy chains to control water level and a larger pool for water traffic.
Emsworth would replaceAllegheny River Lock and Dam No. 1, along with two others. Water levels had risen in the Pittsburgh region, decreasing the need for so many lock systems that close to the Point.
During the 1940s and 50s, Allegheny River Lock and Dam No. 1 was slowly dismantled and the land was bought by private investors. But Grantz said most of the lock and some of the original dam still remain.
“You can see where the water flows over, it bubbles back. If you get a lot of current, you can see where it rolls back, where it goes over the dam and underneath the water,” Grantz said. “So it’s definitely a piece of history.”
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