online_tr55_detention:   TR-55 detention basin storage volume calculator A detention basin in an urban area. Reference:  Natural Resources Conservation Service. (1986). TR-55 Urban Hydrology for Small Watersheds, Chapter 6: Storage Volume for Detention Basins. INPUT DATA: [Sample input file] Watershed (optional):   Units:    SI units (metric) U.S. Customary units (SI units) [U.S. units] Catchment area A (ha) [ac]:      Storm depth P (mm) [in]:      Storm type:    Type I / Type IA Type II / Type III Pre-development peak flow Qo (m3/s) [cfs]:      Post-development peak flow Qi (m3/s) [cfs]:      OUTPUT: Please enter input data and press  Calculate.   Your request was processed at  11:53:31 am on March 23rd, 2026   [ 260323  11:53:31 ]. Thank you for running online_tr55_detention.   [140429]