Apparatus for control of liquids

Claim 1

Apparatus for controlling the rate of liquid discharge from a site comprising at least three liquid retention cells each having a bottom, said cells being arranged in series with respect to the flow path of the liquid through the apparatus, the liquid retention cells being arranged in at least one group which comprises at least three of said cells disposed adjacent one another, an inlet for receiving liquid previously existing at the site and for delivering liquid to an upstream cell of the apparatus and an outlet for discharging liquid from a downstream cell of the apparatus to a discharge line, and transfer orifices which provide liquid communication between adjacent cells in the group, the flow controlling structural dimension of said orifices remaining fixed during all operative states of said apparatus, the or each transfer orifice being located at the bottom of the cells and being configured so as to control the rate of liquid flow between adjacent cells and create a condition whereby there is a dissipation of energy of the liquid between each cell.

Claim 18

A method of controlling the rate of stormwater discharge from a site to a stormwater drain of predetermined capacity, said site being capable of producing a stormwater drain-off rate in excess of said predetermined capacity, said method including the steps of: (a) causing the stormwater to flow to a flow control apparatus having at least first, second and third cells arranged in series with transfer orifices to provide liquid communication between adjacent cells; (b) dissipating energy in said first cell as the stormwater passes therethrough; (c) dissipating energy in the orifice connecting the first cell to the second cell, the flow controlling structural dimensions of the orifice connecting the first and second cells remaining fixed during all operative steps of the method; (d) dissipating energy in the second cell as the stormwater passes therethrough; (e) dissipating energy in the orifice connecting the second cell to the third cell, the flow controlling structural dimensions of the orifice connecting the second and third cells remaining fixed during all operative steps of the method; (f) dissipating energy in the third cell; and (g) discharging the stormwater from the third cell to said drain at a rate which does not exceed said predetermined capacity.

Claim 19

A method of controlling the rate of stormwater discharge from a site to a stormwater drain of predetermined capacity, said site being capable of producing a stormwater drain-off rate in excess of said predetermined capacity, said method including the steps of: (a) causing the stormwater to flow to a flow control apparatus having at least first, second and third cells arranged in series with transfer orifices to provide liquid communication between adjacent cells; (b) dissipating energy in said first cell as the stormwater passes therethrough; (c) dissipating energy in the orifice connecting the first cell to the second cell, the flow controlling structural dimensions of the orifice connecting the first and second cells remaining fixed during all operative steps of the method; (d) dissipating energy in the second cell as the stormwater passes therethrough; (e) dissipating energy in the orifice connecting the second cell to the third cell, the flow controlling structural dimensions of the orifice connecting the second and third cells remaining fixed during all operative steps of the method; (f) dissipating energy in the third cell; and (g) discharging the stormwater from the third cell to said drain at a rate which does not exceed said predetermined capacity.