Children of all ages tackled the giant obstacle course bounce house at Gridley Parks & Recreations revival of Picnic in the Park. GRIDLEY, CA (MPG) - After a one-year hiatus, Picnic in the Park returned to Gridley on Saturday, June 27, with a four-hour event from 11 a.m. to 2 p.m. Using the shaded expanses of Manuel Vierra Park, newly installed Gridley Parks and Recreation Manager Jamie Luevano organized a variety of sports and activities for families to enjoy.