Appendix A - Sewer Calculations

Appendix A - Sewer Calculations

J.E. ANDERSON & ASSOCIATES DATE: 2023/11/22 PROJECT No. 33862 PREPARED BY: CK

PEBBLES – PROPOSED SANITARY FLOW CALCULATIONS

• 2.8 CAP/UNIT (CRD ENGINEERING SPECS – MEDIUM DENSITY)
• 240 L/CAP/DAY (MMCD – ADWF FOR METERED SYSTEM)
• 20 UNITS PROPOSED
• SITE AREA = 2470 m² = 0.247 ha
• i = 0.12 L/s/ha (MMCD – OLD SYSTEM ≥ 25 YRS)

Calculations:

Q_SEWAGE = CAPITA × ADWF × PEAKING FACTOR + I & I

CAPITA = 20 UNITS × 2.8 CAP/UNIT = 56 CAP = P

PEAKING FACTOR = PF = 3.2 / P^0.105 = 3.2 / (1)^0.105 = 3.2

I & I = 0.247 ha × 0.12 L/s/ha = 0.03 L/s = 2561 L/DAY

Q_SEWAGE = 56 × 240 × 3.2 + 2561 = 45 569 L/DAY = 0.53 L/s