Determine the time of concentration, tc, for use in the Rational Method for a drainage basin having a hydraulic path described as follows: Overland flow: average grass, 100r long, 3.5% average slope...

Determine the time of concentration, tc, for use in the Rational Method for a drainage basin having a hydraulic path described as follows: Overland flow: average grass, 100r long, 3.5% average slope Shallow concentrated flow: 200r long, 3.5% average slope Swale (cross section shown below): 500r long, 2.0% average slope.