« Back to Project List

Castle Clinton National Monument

Client: The National Parks Service

This $5.1 million dollar contract is for the restoration of the historic stone masonry, historic roofing, cast iron restoration and the lightning protection replacement for the Castle Clinton National Monument in New York, New York.

Castle Clinton National Monument (CACL) was completed in 1811 as the Southwest Battery part of the defensive system protecting Manhattan. It stood 200 feet offshore, supported by caissons and wood piers. The historic walls are constructed of red Newark sandstone.

The historic wall, comprised of porous sandstone, is deteriorating due to insufficient or inappropriate capping and through ground water penetration. Significant water intrusion through capillary action with the stone was detected. Uneven settling has caused vertical and horizontal cracks and dislocation of individual stones.

In addition, exposure to the elements and environmental pollutants have led to ongoing exfoliation and spalling of the facing stone. The instability of many stones presents an ongoing threat to visitors and staff. This is an extremely hightraffic area of Manhattan, as approximately 3.5 million visitors pass through the Castle annually.

This project will stabilize, conserve, repair, and restore the historic stone walls of the Castle Clinton National Monument. This project includes new capping of the wall where necessary, stabilization, restoration and conservation treatment of this historic and irreplaceable cultural resource. This will be accomplished through replacement, pinning, dutchman, patching and repointing throughout the historic fabric. All original fabric will be retained and conserved.

Click here to download a PDF of this project write-up.