May 15 Corsica Riverfest, noon to 4 p.m. Celebrate the opening of the new Corsica Water Trail at the Wharf on Watson Road, Centreville. Free family event includes kayaking, fishing derby, exhibits. Food available. For information, call 410-6042100 or visit www.qac.org or the Corsica River Conservancy at www.corsicariverconservancy.org.