a. In addition to the purposes outlined under Division 1 of these Design Standards, the purpose of these Standards is to ensure the development of a stormwater management system which will:
1) be of adequate design to safely manage all volumes of water generated upstream and on the site to an approved point of disposal;
2) provide points of disposal for stormwater generated by future upstream developments;
3) prevent the uncontrolled or irresponsible discharge of stormwater onto adjoining public or private property;
4) prevent the capacity of downstream channels and storm drainage facilities from being exceeded;
5) have sufficient structural strength to resist erosion and all external loads which may be imposed;
6) maximize the use of the City's natural drainage system;
7) be designed in a manner to allow economical future maintenance;
8) require the use of design and materials to provide a system with a minimum practical design life of not less than 50 years.
9) incorporate on-site detention when post development site stormwater discharge flow exceeds pre development flow.
10) Best management practice to address per stormwater LID standards.
Alternate materials and methods will be considered for approval on the basis of these objectives.
b. These Standards cannot provide for all situations. They are intended to assist but not to substitute for competent work by professional design engineers.