public void TotalVolumeTester(DesignStorm ds,
                                      decimal impArea, decimal cn, decimal toc, decimal expcumRO)
        {
            var sevt = StormEvent.Make(ds, impArea, cn, toc);

            Assert.AreEqual(expcumRO, 2 * sevt.TotalCubicFeetVolume, "Cumulative Volume");
            // -------------------------------------------------------------
        }
        public void CumRunoffTester(DesignStorm ds,
                                    decimal impArea, decimal cn, decimal toc,
                                    decimal expCumRunOff)
        {
            var sevt = StormEvent.Make(ds, impArea, cn, toc);

            Assert.AreEqual(expCumRunOff, sevt.CumulativeRunOff,
                            "Total Volume in Cubic Ft");
        }