undated Atlas Obscura post on McMillan

A neighbor passes along this Atlas Obscura post on the McMillan Sand Filtration site.  I can't find a date associated with this post.

I have copied the first two paragraphs of this post.

Here is the link to read the entire entry and to see the images.

Shortly after the new city reservoir was completed at Howard University, Congress authorized funds for an adjacent filtration site to address the public health situation. The facility relied entirely on sand to clean the water; at the time, this method scaled better and was more cost effective than using chemicals.

“Raw water” came in from the reservoir next door and slowly percolated through the sand in 25 vaulted underground cells before making its way out into District taps. The 4-foot lining of sand actually did a remarkable job at removing bacteria and sediment from the water.

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