Drain in Poughkeepsie, NY

This drain is located on the west side of Route 9, across from the Abraham Fort Homestead. There is a structure inside and I do not know what it is. When I took the pictures, the hill was wooded, but in late 2011 the area was being redeveloped, but the drain was still there.  I have not gone back since then to check if it is still present.

Location:  It was in the vicinity of here (41.641383, -73.920008).