🌊 Manning Formula (V = [1.486/n] x R^(2/3) x S^(1/2), Min 2.0 FPS Self-Cleansing)

Gravity Sewer Pipe Velocity & Slope Calculator

Size underground sanitary and storm gravity sewer pipes under ASCE Manuals of Practice & Ten States Standards using Manning's open-channel equation: calculate flow velocity and discharge capacity (maintaining minimum self-cleansing velocity 2.0 FPS at partial/full flow using roughness coefficient n = 0.009-0.013 for SDR-35 PVC / HDPE), and civil utility profits.

1. Project & Operating Inputs

Gravity Sewer Main Installed (Linear Feet e.g. 2,400 Linear Feet Main)

Pipe Diameter (Inches e.g. 12.0" SDR-35 PVC Gravity Pipe)

Customer Bid Price for Supplied, Trenched & Bedded Sewer Pipe ($ / Lin Ft)

ASTM D3034 PVC Pipe, Trench Box Shoring, #57 Stone Bedding & Crew ($ / Ft)

2. Financial Breakdown & Yield

MANNING FORMULA GRAVITY SEWER

Turnkey Gravity Sewer Contract Profit

Underground Civil Contractor Margin

0.0%

Gross Revenue / Bill

Total Project CapEx

Operating / Material Cost