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.
Road gutter design.
A 0 area of gutter road section beyond the depression width ft 2 or.
When a curbstone is present a gutter may be formed by the convergence of.
The allowable spread length generally determined by state or local regulations is based on the road s classification.
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.
Department recommendation for design is the use of the rough texture values.
Chapter 7 streets inlets storm drains january 2016 urban drainage and flood control district 7 1 urban storm drainage criteria manual volume 1.
Michigan design manual road design chapter 6 surfacing and shoulders index continued 6 06 15 minimum curb and gutter grades 6 06 16 curb and gutter for erosion control 6 06 17 concrete curb cap 6 06 18 deleted 6 06 19 driveway openings 6 06 20 curb and gutter adjacent to hma base course 6 07 concrete divider 6 08 sidewalk.
Spread is the top width of the flowing water on the road measured from the curb.