Parsed SWM report

1485 Williamsport Drive & 3480 Havenwood Drive

1485 Williamsport Dr. & 3480 Havenwood Dr. Development · Redevelopment · 2024-05-23

Consultant: LEA Consulting Ltd. Model: UNKNOWN Revision: Rev 4
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
discharge reduction — not documented
0%
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
combinable O&A sub-credits — not documented
0%
Net credit
Capped at 50% of annual stormwater charge
40%
Pre vs post peak discharge
Storm eventPre-dev (L/s)Post-dev (L/s)Δ
2-yr35.5167.86+91%
5-yr47.1591.22+93%
10-yr55.09112.36+104%
25-yr65.16129.05+98%
50-yr72.67144.62+99%
100-yr80.22159.41+99%
Stormwater controls (5)
Underground storageTank 1 (Layfield Aquabox)
Storage volume101.4 m³
Outletorifice

Quantity control for sub-catchment PC-1 draining to Havenwood Drive. 78.62 m3 module storage + 22.78 m3 granular stone surrounding. 250 mm orifice tube. Allowable release rate 80.22 L/s (100-yr). Also provides 28.45 m3 water balance retention volume.

Underground storageTank 2 (Layfield Aquabox)
Storage volume21.7 m³
Outletother

Quantity control for sub-catchment PC-2 draining to Williamsport Drive south. 15.55 m3 module storage + 6.12 m3 granular stone surrounding. Inlet control device on OGS MH 12 (200 mm PVC STM pipe) as alternative to 85 mm orifice tube (below 100 mm minimum). Allowable release rate 9.25 L/s (100-yr). Also provides 5.67 m3 water balance retention volume.

Oil-grit separatorOGS MH7 - Stormceptor EF04 (PC-1)
Outletother

Forterra Stormceptor EF04 for water quality treatment of sub-catchment PC-1. Installed downstream of underground storage tank.

Oil-grit separatorOGS MH12 - Stormceptor EF04 (PC-2)
Outletother

Forterra Stormceptor EF04 for water quality treatment of sub-catchment PC-2. Also acts as inlet control device for Tank 2.

InfiltrationBottom infiltration from storage tanks

Infiltration from the bottom of proposed storm tanks as a method to address water balance criteria.

Best management practices (10)
Underground storage tank (Layfield Aquabox)Oil/Grit Separator (Forterra Stormceptor EF04)Clean roof creditSoft landscaped areaInfiltration from storage tank bottomRainwater harvesting / grey water reuseIrrigation of trees and plantsSediment control fenceMud matCatchbasin filter fabric
Site characteristics & report metadata
Project1485 Williamsport Dr. & 3480 Havenwood Dr. Development
Project typeRedevelopment
DeveloperStarlight Group Property Holdings Inc.
Existing land useresidential
Proposed land useresidential
Site area2.22 ha
Water balance capture5.0 mm
TSS removal target80%
Allowable release rate80.2 L/s
Quality control methodclean roof credit + landscaped area credit + oil-grit separator (Forterra Stormceptor EF04)
Extraction audit
Confidence: high Completeness: 83% Source: 180-page PDF Extractor: PARCELFLOW v1 Validation: passed
Source PDF: site-servicing-and-stormwater-management-report-may-2024-oz-18-014-w3.pdf (180 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.