This subchapter sets forth the technical criteria necessary to design storm water channels and ditches using conventional design procedures. These procedures shall be applied to roadside and rear yard ditches and highly urbanized channels. Open channels provide many advantages in the management and control of storm water runoff. Such channels provide for natural infiltration of storm water into the ground water supply and extend the time of concentration (Tc), helping to maintain the runoff rate nearer to that which existed prior to development. The objective of open channel flow design is: to determine a channel slope and size that will have sufficient capacity to prevent undue flooding damage during the anticipated peak runoff period; and to determine the degree of protection based on stream velocity to prevent erosion in the drainage channel.
(Ord. 012-118, passed 10-8-2012)