USACE Sandbag Levee Bags and Sand

ScopeA sandbag levee is a pyramid, and the USACE Flood Fight Handbook's table of bags per linear foot -- 6, 21, 45, 78, and 120 at one to five feet -- is exactly 1.5 H + 4.5 H^2, a cap term and a triangular body. Written as a formula it extends to any length and to intermediate heights without interpolation, and it shows why raising a levee is expensive: the third foot costs 24 bags per foot and the fifth costs 42. A 3 ft levee 500 ft long in front of a neighborhood takes 45 bags per foot, 22,500 bags, and 450 tons of sand at 40 lb per bag, on a 9 ft wide footprint, because the base is three times the height. The same length at 2 ft takes 10,500 bags and 210 tons -- one foot less height saves more than half the bags, which is why the height is set from the forecast crest plus freeboard rather than rounded up for comfort. Bags are filled one-half to two-thirds full, about 35 to 40 lb, light enough to pass hand to hand for hours. The handbook prefers 3 ft and treats 5 ft as the practical limit; above it the calculator flags that an earth levee or a manufactured barrier is the right tool. It does not assess the foundation, seepage and sand boils, stability against the water load, the forecast crest, labor, sheeting, or single-row walls against a structure. The USACE Flood Fight Handbook, the local emergency manager, and the USACE district govern.

Formula or tablebags per linear foot N = 1.5 H + 4.5 H^2 (H in ft; reproduces USACE Table 2.1 exactly: 6, 21, 45, 78, 120 at 1-5 ft); total bags = N x length, rounded up; sand tons = bags x fill weight / 2,000; base width = 3 H; 3 ft preferred and 5 ft practical height limits flagged.

Source and editionUSACE St. Paul District, Flood Fight Handbook (2016), Sections 2.3 and 2.5 and Table 2.1, with the USACE sandbag guidance of about 40 lb of sand per bag. The local emergency manager and the USACE district govern.

Free accessThe USACE Flood Fight Handbook is a free federal publication; the table is reproduced as its exact quadratic fit.

What governsEstimate. AHJ and licensed professional govern.

API field namesheight_ft, length_ft, fill_weight_lb, bags_per_ft, total_bags, sand_tons, base_width_ft

• USACE cross-section a pyramid levee with a base of three times its height, Table 2.1 bags per footUSACE Flood Fight Handbook Table 2.1
• Fill weight about 40 lb of sand per bag, one-half to two-thirds fullUSACE sandbag guidance
• Height limits 3 ft preferred maximum, 5 ft practical limitUSACE Flood Fight Handbook Section 2.5