Why is the paint peeling off the Lincoln Memorial Reflecting Pool? An investigation
www.scientificamerican.com
... Poor preparation and a failure to properly apply the coating may be just a few of the reasons why the Reflecting Pool's new paint job appears to be peeling off
The Lincoln Memorial Reflecting Pool's makeover was supposed to inspire patriotism, but chunks of material peeling off the pool's surface have instead garnered more puzzlement and speculation.
President Donald Trump ordered the pool's renovation in April, and that order included painting its floor and walls blue. Yet within weeks of the work's completion, photographs and videos of floating chunks of a cerulean material that appears to have detached from the pool's walls have gone viral. This material is polyurea coating"a fast-curing and durable surface membrane that can seal in water and is often used to coat swimming pools.
We spoke to engineering and pool experts to find out what could be going wrong at the beleaguered monument.
For one, the blue material likely has no direct relation to the large algal blooms that are also plaguing the monument, according to Tim Auerhahn, chairman of the Aquatic Council. Nor is it merely a reaction to the hydrogen peroxide that the National Park Service (NPS) dumped into the water in an apparent effort to kill the algae"although that likely didn't help, either.
At this point, pinning the blame for the floating coating on any one factor would be premature, says David McFayden, CEO of the paint and coating inspection company KTA-Tator.
Auerhahn agrees: "The failure of the adhesion to the substrate of that product probably could have been caused by many factors," he says. Still, based on the videos of workers dumping hydrogen peroxide from the edges of the pool, he says that "it could have contributed to the issue, but it's probably not the only cause." The Department of the Interior, which oversees the NPS, did not respond to a request for comment.
Hydrogen peroxide can be used as a paint stripper, but the water in the pool would likely dilute it to the point that it couldn't cause the current level of damage, he adds. ...
