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Opens on the book's own wall. Change any number to your own and press Calculate.
Enter a depth and press Calculate.
From the book, Chapter 7. Push per meter of wall = ½ × ρ × g × h² (ρ = 1,000 kg/m³ fresh water, g = 9.81). 300 mm pushes 441 N per meter; 600 mm pushes 1,766 N. In feet: ½ × 62.4 × h² pounds per foot (64.0 for salt water).
A flood wall should be designed by a licensed engineer (FEMA P-312). Water also goes under and around a wall; the push is only one of the numbers. Prices are illustrative US home-center prices from October 2026, shown without a currency sign; put in your own. Everything stays in your browser: no sign-up, nothing stored.