35. Where simulated rain intensities or levels have return periods equal to or less than the service level of a simulated minor drainage system, no “node” type element of the computer model may be flooded on the surface for the duration of the simulation.
The service level of the minor drainage system is the annual probability that part or all of the minor network flow surcharges and corresponds to the return period according to T = 1/P where T is the return period in years and P is the annual probability that part or all of a minor network flow surcharges at least once.
871-2020O.C. 871-2020, s. 35.