Apparently, according to DC Parks & Rec, and not after this weekend.
"Thank you for your email to DC Department of Parks and Recreation.
I attached information Ref. Outdoor pool closures.
Hains Point or East Potomac pool close October 6/12.
Btw, the Parks Dept listens to requests for keeping Hains open later, nice especially since many know want to do OWS or open-air swims or approaching races. Based on past experience, it also will tend to close the pool earlier than announced if few swimmers are showing up.
It doesn't hurt to give the Dept your thanks or opinion on this: