Engineering Tool

OGS Sizing Portal

Get your sizing report in minutes, not days. Enter your project details below.

Contact

Project

Technical

Contact Information

Who we should address the sizing report to. The report is emailed to this address.

First Name *

Last Name *

Phone *

Email *

Company Name *

Engineer City *

Project Information

Where the unit will be installed. These details appear on the report and determine which rainfall data we use.

Project Name *

Project City *

Project Address

OGS Designation

Optional. The structure label from your drawings, printed on the report.

Date Required By *

Rainfall Station *

Technical Data

The drainage parameters used to size the unit. If you're unsure of a value, our engineering team reviews every request before the report is issued.

OGS Model *

Top Inlet PanInclude top inlet pan

Contributing Area (ha) *

Runoff Coefficient *

Value between 0 and 1 (e.g., 0.85 for impervious surfaces)

Your contact and project details are used to prepare and send your sizing report. See our Privacy Policy.

Why Use Our Portal?

Instant Verification

Quickly verify preliminary sizing feasibility.

Official Report

Receive a stamped engineering report for your submission.

Optimization

Our team reviews every request to save you money.

Runoff Coefficient Guide

Asphalt/Concrete0.85 - 0.95

Rooftops0.75 - 0.95

Gravel0.4 - 0.6

Lawns (flat)0.25 - 0.35

Lawns (steep)0.35 - 0.45

Parks/Gardens0.2 - 0.35

Need Assistance?

Our engineering team is available to help with complex site requirements.