This year marks the 15th anniversary of humanitarian groups putting water in the desert for migrants. We’ll interview the man who started it, and ask whether there’s a way to know if it’s effective. Guest: Rev. Robin Hoover, President, Migrant Status, Inc. Roundtable: Michel Marizco, reporter, Fronteras Desk Tim Steller, columnist, Arizona Daily Star Dylan Smith, Editor & Publisher, TucsonSentinel.com