(a) "Acre" means 43,560 square feet.
(b) "Detention" means storage of drainage for a short period of time and then release of the same at a controlled rate. The storage area may remain dry during nondrainage periods.
(c) "Flow (Q)" means the volume of liquids traveling through a vessel, such as a pipe, open ditch or orifice, per unit time, such as seconds.
(d) "1 Ft.3" means 7.48 gallons.
(e) "n year" means, in theory, an intensity of rain that should occur in (n) years (inches/hour).
(f) "Orifice" means a device that controls the inlet and outlet of flow.
(g) "Qn" means, in theory, a flow that should occur one in (n) years.
(g) "Retention" means storage areas that maintain a planned permanent level of water for a considerable length of time for aesthetic, agriculture, consumptive, public safety or other uses, released at a controlled rate.