Quick addendum (since I had a bit of time to kill I circled a fair amount before actually picking our daughter up). It looks like a number of the tents that had been occupying part of the sidewalk space on M and L streets (see https://www.washingtonpost.com/local/the-new-dc-outside-an-rei-that-sells-tents-desperate-people-are-living-in-them/2017/12/14/a47a8d1e-e0c5-11e7-8679-a9728984779c_story.html?utm_term=.8efb0b1eafe9 for more of that story) have relocated to the K Street underpass. Those sidewalks are quite a bit narrower, so if you go that way, you’ll need to take the lane to avoid a bunny hop down the large curb to avoid running over a tent.
Also, if you detour to L street to get around, please be mindful that the block between 2nd and 3rd is a minor disaster zone; the construction site had a water pipe burst around new year’s, which (combined with the construction traffic) has led to a lot of sunken in manhole covers and potholes and the like.
So short version: it’s a mess, and be careful out there.
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