CHAPTER 4 DRAINAGE DESIGN
2021-2-17 · EXAMPLE: If a road culvert is to last 25 years with a 40% chance of failure during the design life, it should be designed for a 49-year peak flow event (i.e., 49-year recurrence interval). When streamflow records are not available, peak discharge can be estimated by the 'rational' method or formula and is recommended for use on channels draining less than 80 hectares (200 acres):
Get Price