Celebrate at Barton Springs, 5:30 til 10:00 p.m., south side, Barton Springs, live music featuring friends of the springs, Eliza Gilkyson, Bill Oliver, Minor Mishap Marching Band and others; Karen Kocher’s “Common Ground” documentary film; Dean Rindy’s original SOS short film; poetry with Thom the Poet; discussion; swimming, and lots of cold watermelon. Bring your towels and blankets.