Canyon Lake prevented flows of up to 125,000 cubic feet per second heading into New Braunfels according to this graph from the U.S. Army Corps of Engineers. Note the Flow on July 5, 2002 without Canyon Lake exceeding 125,000 cfs. With Canyon Lake, the flow in New Braunfels was held at less than 70,000 cfs. An estimated $38.6 Million in damages were prevented.