Pond CN, Stage-Storage, and ToC Calculations

💧 Pond Calcs: CN, Tc & Stage-Storage (Excel Template)

A clean and simple Excel file to help you stay organized while running common pond calcs — including Curve Number (CN), Time of Concentration (Tc), and Stage-Storage.

Perfect for students, interns, and young professionals in land development or water resources.

📦 What’s Inside:

• ✅ Composite Runoff Coefficient (C) breakdown
• ✅ Weighted Curve Number (CN) table
• ✅ Tc calculator using the TR-55 method (sheet + concentrated flow)
• ✅ Stage vs. Storage table for pond volume tracking
• ✅ Built-in tips, equations & clean formatting

⚠️ Disclaimer:

This spreadsheet was developed using general civil engineering principles and publicly available methodologies, such as those found in the TR-55 manual. It is intended for educational and reference purposes only and should not be used as a substitute for professional engineering judgment, sealed documents, or jurisdiction-specific standards. Users are responsible for verifying all calculations and ensuring the tool is appropriate for their specific project or application. The creator assumes no liability for any outcomes resulting from the use of this file.

All units are Imperial [US].