Dear Penguin,
I figure you will be able to get to the bottom of this pressing question: Why is Ellsworth Drive always wet?
– Gary Hewitt
Dear Gary,
It’s a damned good question, one that we in The Penguin newsroom have asked ourselves. Of course, the sidewalks along Ellsworth Drive are a little wet today from snow, but they retain that slick, “fresh out of the shower” look even on the driest days.
So what gives?
According to Jennifer Nettles, property manager for the Downtown Silver Spring shopping center, the brick sidewalks are mopped (her word) every morning. It’s just a matter of keeping the place looking clean, she said.
But science also could be at play here, said Gary Stith, who recently left his gig as Silver Spring’s regional director for a swank new job as deputy director of planning with the department of general services.
Late last year, the shopping center used a magnesium-based salt to keep the sidewalks from icing over. The problem was, that salt drew moisture from the air, causing water to bead on the brick even on relatively dry days, Stith explained. The shopping center has since switched to another compound to keep the place from getting too frosty, he added.
(If any chemists out there wanna get in on this explanation, holler back.)
That’s the story, Gary — mop or magnesium salt. I’ll leave it to you to determine which story will impress your coworkers.
Sincerely,
Jennifer Deseo
Editor, The Silver Spring Penguin
Photo: Chalk grafitti makes a statement during the 2007 Photo Walk and Protest on Ellsworth Drive. Courtesy of Flickr user Sabine01.
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I don’t find the mopping explanation at all convincing, unless they also mop at night. Whenever I walk home from the gym in the evening I pass through that area, and the sidewalks are often very wet. I doubt that any water left on the sidewalk in the morning would stay there all day long. In fact, I find the water to be a minor hazard during colder evenings because the sidewalk can get pretty slick.
Seems more likely that the bricks absorb moisture then ooze it back out. One evening after a rain, a friend dropped me off and the bricks were wet and slippery, much more so than the concrete sidewalk I got to about 15 min. later. These bricks should be rougher or less permeable.
Rougher would be a bit more challenging to clean. However, the powers-that-be should weigh that against the opportunity cost of people who are afraid to plant their shoppy little feet on dem slippery little devils. I’m able-bodied and know how to fall in the least harmful way. But everybody can get creeped out feel-like-I’m-on-a-skateboard-when-I’m-not experience.
I know that they do mop these bricks. The best/worst example of this was on inauguration day, when it was below freezing. I was walking along Ellsworth watching people slip and slide all over the the place on the bricks. Then, I finally made it to a red-jacketed DTSS employee who was in the process of mopping (aka icing) all the sidewalks! Not the brightest move on a freezing cold day.
A special place in Valhalla for the Penguin’s tracking this down. I think I’ll go with the magnesium chloride (I’m assuming) explanation at work – I have a chemist next door. Maybe the mopped bricks absorb water that gets drawn up by the MgCl2. Though the wetness seems to come on non-freezing days as well.
I’ve been wondering why the bricks were wet on my way to and from work everyday. The property managers should rethink their strategy: on colder days the bricks get very slick. It’s a lawsuit waiting to happen. It’s also a waste of water. Wouldn’t sweeping do the job most days?
Thank you, Jennifer & all for ferreting this one out! If they have to wash the bricks, hope they are using gray water. Wash water or rain water, the bricks soak up & ooze. There oughta be a way to stop that.
I am glad somebody asked this. I thought I was imagining things.