The Snyder Industries 3900 Gallon ASTM Black Heavy Duty Vertical Storage Tank is a full-size bulk storage vessel molded from high density linear polyethylene, standing 163 inches tall on a 90 by 90 inch square footprint. It carries a 1.9 specific gravity rating, which is the number that tells you how heavy a liquid this tank is built to hold. Water has a specific gravity of 1.0, so at 3,900 gallons of water the tank sits at roughly 32,526 pounds of contents, well inside its structural envelope. That 1.9 rating raises the ceiling to a maximum rated contents weight of about 61,799 pounds. One thing to understand before you fill it: that weight limit, not the 3,900-gallon volume, governs a denser liquid. A fluid heavier than water hits the 61,799-pound ceiling before the tank is full, so your usable fill volume drops as density rises. Do not fill a 1.5-specific-gravity liquid to the 3,900-gallon brim assuming the shell holds 3,900 gallons of anything.
Why the heavy-duty 1.9 shell
If your install is water-only today, the load is 32,526 pounds and a lighter-rated tank would carry it. This black heavy-duty shell is the buy when future duty may shift to brine, slurry, or a denser process fluid, so you do not re-tank later. The extra rating is the reason to choose this SKU rather than a standard water-only vertical. Just remember the seal side has to match the service: for anything denser or more aggressive than water, confirm the flange gasket and threaded-fitting seal material are rated for that fluid, because the shell's 1.9 headroom is only usable if the gasketed penetrations are compatible too.
Fittings and access
Per the technical drawing on this page, this Snyder black tank is configured with a flange, an 18-inch polyethylene threaded and vented fitting, a manway with 15-inch access, a 10-inch by 12-inch S.U.M.O. fitting, and a flat S.U.M.O. fitting. The 15-inch manway gives you a real inspection and maintenance opening at the top. The vented fitting matters on a tall closed vertical like this: keep that vent clear in service, because a blocked vent on a tank drawing down at volume can pull a vacuum and deform the shell. Confirm your outlet and plumbing plan against the drawing before you order, since fitting positions on a 163-inch tank drive how you set your pad and pump.
Weight, pad, and sizing
Plan your foundation around the full load, not the empty shell. Size the concrete pad to cover the roughly 90-inch by 90-inch square base and to carry the filled weight, from 32,526 pounds of water up to the 61,799-pound rated ceiling. That underestimate is the single most common mistake buyers make on a tank this tall. Our Tank Sizing Calculator and Tank Sizing Guide help you match capacity to demand, and our guide on concrete pad sizing for above-ground polyethylene tanks walks through the ACI framework. If this is a private fire-protection or rural reservoir install, see our fire-water reservoir tank design guide for NFPA 22 sizing discipline.
This vertical storage tank ships LTL freight from the Snyder plant in Lincoln, Nebraska, quoted live to your ZIP. Get a number in seconds with our Freight Cost Estimator, or call 866-418-1777 and we will quote the delivery and confirm fitting configuration before your order goes to production.
