UNSTABLE GROUND: Sinkholes around storm water and sewer pipes at the intersection of Reservoir Road and Glover Archbold National Park draw the attention of a DC Water maintenance crew on Wednesday, Feb. 27, 2019. Nearby horizontal collection systems connect at the site and then spill into a nearly 40-foot deep vertical, brick-lined pipe that feeds a large main that runs under the center of the park en route to the city’s sewage treatment facility. The crew planned to check for cracks in the pipe that might drain and destabilize surrounding soil. Photo Credit: John A. Bray