Heavy rain has closed not only campgrounds and picnic areas in the Pike National Forest, but also a stretch of the South Platte River. Continued rain over swollen rivers and full reservoirs has put a damper on recreation just before one of the first full weekends expected to be sunny and dry in a long time. The sheriff's offices in Douglas and Jefferson counties have closed the South Platte River and its North Fork until further notice "out of an abundance of caution," the Douglas County Sheriff's Office wrote in a news release issued Wednesday evening.