Shoring Up the Lighthouse’s Future
Aerial photo of the Middle Ground Flats by Andy Milford. The Flats are very visible today, but in the 19th century, they were completely submerged at high tide.
When you picture a lighthouse, it’s easy to imagine the structure sitting at the edge of a majestic clifftop or holding its own out on a little rocky island at sea. For the Hudson-Athens Lighthouse, the story is a bit different. Rather than being built on the shoreline or on a small island, the Hudson-Athens Lighthouse had to be situated in the middle of the Hudson River to protect traffic from the Middle Ground Flats: a skinny, silt-based island. While the tree-covered Middle Ground Flats is now very visible, the island started off as a muddy sandbar. This mudflat would be completely submerged at high tide, often causing ships to run aground. It is rumored that even Henry Hudson’s Halve Maen got stuck on the flats on its original 1609 journey upriver.
To avoid this hazard, the Hudson-Athens Lighthouse was built close to the southernmost point of the flats. Without an island in place to support the structure, the late-19th century engineers got creative. Close to two hundred wooden pilings, made from trees found on the shore, were driven fifty feet into the riverbed using steam power. A large granite pier topped the pilings to make the Lighthouse’s base. In order to protect the foundation from winter and spring ice floes, the north end of the base was shaped like the prow of a ship. Riprap (large boulders) completed the foundation, armoring the Lighthouse against water erosion. Then, like a candle on a wood-and-stone cake, the two-story, Second Empire style brick Lighthouse was built on top.
So, while the Hudson-Athens Lighthouse is not pounded by daily, 40-foot waves, it is essentially standing on stilts atop a massive tidal river. And after 146 years, erosion has taken its toll. The wooden pilings have loosened or rotted, or both! Years of ice floe have knocked away the protective rip rap boulders. Even the granite foundation has shifted, causing the exterior brickwork to crack. The Hudson-Athens Lighthouse is in need of a serious “baselift.”
To that end, the Hudson-Athens Lighthouse Preservation Society (HALPS) formed a committee to assess the Lighthouse’s needs. Back in 2007, the committee commissioned an underwater study to check on the pilings. As a result, 53 eroded pilings underwent rejuvenation in 2008. Worn tops were cut off, replaced with new wood, and reattached with metal collars for additional stability. Some pilings were capped with steel tops as well. This vital repair work was funded thanks to a matching grant between the Bank of Greene County and New York State.
Important work has been done, but the tides continue to affect the Lighthouse’s base. The pilings’ renovation was intended as a temporary measure to stabilize the Lighthouse, and now, HALPS is looking for a more permanent solution. The committee is currently pursuing a second underwater study using LiDAR, which will offer a more accurate picture of the base’s condition. After the LiDAR study, the engineers will likely recommend building an entire steel cofferdam around the Lighthouse. Underwater construction work? Sounds expensive! And you would be right.
While the final figures aren’t available yet, HALPS needs to raise at least $2.5 million to fund the project from the earliest phases of riverbed analysis to the final construction of the foundation protectant. HALPS hopes to have the underwater work completed by 2024: the Lighthouse’s Sesquicentennial year and the 40th anniversary of HALPS’ involvement with the Lighthouse.
Interested in keeping the Lighthouse above water level? Take a socially-distanced tour, send a donation via the HALPS website, or keep an eye out for fundraising activities by joining the HALPS mailing list. With your help, the Lighthouse can shine for many years to come!