Credit scorecard — Mississauga bylaw
Each category awards a maximum percentage of the annual stormwater charge as credit.
Evidence is extracted directly from the source PDF — no manual review.
✓Peak Flow
pre-vs-post controlled across multiple storms; avg reduction 69%
40%
✓Water Quality
TSS removal 80% (enhanced)
30%
✓Runoff Volume
water balance retains 5 mm on site (2% per mm, max 30% at 15 mm)
30%
✓Operations
BMPs + P.Eng present; sub-credit detection pending — full 20% requires explicit O&A items
20%
Net credit
Capped at 50% of annual stormwater charge
50%
Pre vs post peak discharge
| Storm event | Pre-dev (L/s) | Post-dev (L/s) | Δ |
|---|
| 2-yr | 55.09 | 18.81 | −66% |
| 5-yr | — | 22.5 | — |
| 10-yr | — | 25.51 | — |
| 25-yr | — | 29.34 | — |
| 50-yr | — | 33.04 | — |
| 100-yr | 129.42 | 36.07 | −72% |
Stormwater controls (4)
Underground storageStormwater Management Tank (P1 Level)
Storage volume206.2 m³
Treatment volume18.5 m³
Outletorifice
Outlet invert135.25 m
100-yr HGL136.78 m
100 mm diameter Orifice Tube outlet control device; tank area 135.2 m2; located at P1 level northeast corner of underground; includes 74.4 m3 reuse sump below outlet invert; constant groundwater inflow of 0.63 L/s included in calculations
Oil-grit separator1200 mm Up-Flo Filter
Hydro International Up-Flo Filter with CPZ Media; installed downstream of storage tank; provides Enhanced Level water quality protection (80% TSS removal)
Green roofGreen Roof
Green roof included in pervious area calculations for post-development catchment 201
Rainwater harvesting / reuseWater Reuse Sump
Storage volume74.4 m³
Outletother
Located below outlet invert of stormwater management tank; used for on-site irrigation reuse; 72-hr irrigation demand is 21.12 m3; pump to be designed by Mechanical/Irrigation Consultant
Best management practices (8)
Underground Stormwater Management TankOrifice Tube Outlet Control DeviceUp-Flo Filter with CPZ MediaGreen RoofWater Reuse/Rainwater Harvesting (Irrigation)Silt FencingRock Mud MatSilt Sacks
Site characteristics & report metadata
Project1470 Williamsport Drive Residential Development
Project typeRedevelopment
Developer1470 Williamsport Holdings Inc. c/o Compten Management Inc.
Existing land useresidential (6-storey apartment building with surface parking and landscaped areas)
Proposed land useresidential (two 12-storey residential towers with 1-storey podium, 283 units)
Site area0.59 ha
Water balance capture5.0 mm
TSS removal target80%
Allowable release rate47.5 L/s
Quality control method1200 mm Hydro International Up-Flo Filter with CPZ Media installed downstream of underground storage tank
Extraction audit
Confidence: high
Completeness: 92%
Source: 103-page PDF
Extractor: PARCELFLOW v1
Validation: passed
Source PDF: Functional-Servicing-and-Stormwater-Management-Report-OZ-OPA-25-7-W3-October-2025.pdf (103 pages)
Open source PDF →
Starter package
Download credit application package »
10-page PDF: pre-filled Form 2703, starter P.Eng report skeleton, submission checklist. Engineer reviews, adds site inspection + O&M plan, certifies + submits.
Download PDF »
How to read this page. Every value above was extracted from the source PDF by the
PARCELFLOW report parser, which combines a layout-robust template detector with a
validated extraction stage tuned to Ontario Functional Servicing and Stormwater
Management reports. The four-category scorecard maps the parsed evidence onto
Mississauga's credit bylaw. Numbers are estimates — engineering review still required
before submitting a formal credit application to the City.