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Network & HydraulicsBS EN 752

Hydraulic Grade Line Calculator

Manhole-to-manhole HGL profile with energy losses, surcharge and freeboard checks.

1 Network Setup

2 Pipe Definition

3 HGL Analysis

4 Results & Export

Step 1: Network Setup

Project Information

Project Name

Site Reference

Engineer Name

Date

Tailwater Level (mAOD)

The downstream receiving sewer soffit or watercourse level in metres Above Ordnance Datum

Minimum Freeboard to Cover (m)

Minimum clearance between HGL and cover level; typically 0.3–0.5m per BS EN 752

Minimum Velocity (m/s)

Self-cleansing velocity per BS EN 752:2017 (typical 0.75 m/s)

Maximum Velocity (m/s)

Erosion protection limit (typical 3.0 m/s)

Step 2: Define Pipe Network

Add pipe runs to model your SuDS network. You can add up to 10 pipes in a single branch.

Step 3: Hydraulic Grade Line Analysis

Pipe	Length (m)	Diameter (mm)	Gradient	Full Capacity (l/s)	Flow (l/s)	Util. (%)	Velocity (m/s)	Friction Loss (m)	MH Loss (m)	HGL Up (mAOD)	Freeboard (m)	Status

Step 4: Results Summary & Export

Engineer's Notes Optional, included in PDF report