Branthaven Queen West Inc. - Environmental Compliance Approval (sewage)

The ministry has issued a new ECA for the establishment of stormwater management works and wastewater infrastructure works located in the City of Brampton, for the collection, transmission, treatment and disposal of stormwater runoff from a total catchment area of 1.21 hectares, to provide enhanced level water quality protection and erosion control, and to attenuate post-development peak flows to allowable peak flows for all storm events up to and including the 100-year storm event, discharging to a tributary of Huttonville Creek, consisting of the following:

• rear yard swales on easement, from Queen Street West to approximately 220 metres southeast of Queen Street West, discharging to the suburface infiltration trenches described below
• subsurface infiltration trenches (catchment area 0.22 hectares), a total of twelve (12) infiltration trenches, known as infiltration trenches A to L, located on the rear yards of Block 1 to Block 11, having a length ranging from 7.8 metres to 40 metres, a width ranging from 0.5 metres to 1 metre, a base area ranging from 7.8 metres to 20 metres, a maximum allowable storage depth ranging from 0.15 metres to 0.6 metres and a total maximum available storage volume of approximately 24 cubic metres, comprised of a 19 millimetre diameter clear stone layer, complete with a 150 millimetre perforated storm sub-drain installed in the clear stone layer, infiltration trenches on Blocks 8 to 11 discharge at a maximum discharge rate of 1 L/s to the wetland located west of the site, and emergency overflows from all infiltration trenches discharging to storm sewers on easement
• storm sewers on easement, perpendicular to Queen Street West, from Queen Street West to approximately 230 metres southeast of Queen Street West, discharging to the proposed oil and grit separator, and underground storage chambers, described below
• oil and grit separator (catchment area 1.21 hectares): one oil and grit separator, Jellyfish Filter Model JF6-5-1 or Equivalent Equipment, located on the southeast side of the proposed development, upstream of the south storage underground storage chamber, indicated below, providing Enhanced Level of protection, having a sediment storage capacity of 5205 litres, an oil storage capacity of 848 litres, and a maximum treatment rate of 27.8 litres per second, receiving inflow from the storm sewers described above, discharging via a 250 millimetre diameter outlet pipe to underground storage chambers located on the south side of the proposed development
• underground storage chambers (catchment area 1.21 hectares), provided in 35 Stormtech MC-4500 chambers or Equivalent Equipment, located on the north side of the proposed development, having a total length of 15 metres, a width of 11.6 metres, a base area of 179 square metres, a maximum allowable storage depth of 1.8 metres and a maximum available storage volume of 226 cubic metres, comprised of a deep clear stone layer, wrapped in an impermeable membrane, and an emergency overflow outlet discharging via a 600 millimetre superpipe to the underground storage chambers described below
• underground storage (catchment area 1.21 hectares), provided in oversized storm sewers, having a total length of 173.3 metres and diameter of 600 millimetres, located between both underground storage chambers systems, having a maximum available storage volume of 49 cubic metres, discharging to the south underground storage chamber, described below
• underground storage chambers (catchment area 1.21 hectares), provided in 77 Stormtech MC-4500 chambers or Equivalent Equipment, located on the south side of the proposed development, having a total length of approximately 27 metres, a width of approximately 25 metres, a base area of approximately 385 square metres, a maximum allowable storage depth of 2.76 metres and a maximum available storage volume of 618 cubic metres, comprised of a clear stone layer wrapped in an impermeable membrane, via a 600 millimetre diameter pipe to control Manhole 10 equipped with one Hydrovex 50VHV-1 flow control device or Equivalent Equipment, one 75 millimetre diameter orifice, and one 100 millimetre diameter orifice, allowing a maximum discharge of 18.4 litres per second under the 100-year storm event to a wetland approximately 50 metres south of the proposed development;
• pocket wetland (catchment area 1.21 hectares), approximately 6 metres long and 12 metres wide, located approximately 50 metres south of the proposed development, providing flow dissipation and erosion protection, discharging to the tributary of Huttonville Creek

including erosion/sedimentation control measures during construction and all other controls and appurtenances essential for the proper operation of the aforementioned works