The Norwesco 165 Gallon Black Vertical Storage Tank is a 56-inch-tall poly tank on a compact 31 x 31-inch footprint, rated to a 1.5 specific gravity. That combination - real vertical capacity over a square-yard-and-change of floor space - is why it stays a go-to vertical storage tank for water, rainwater catchment, and bulk liquid handling where headroom is plentiful but floor space is tight. Black resin blocks light, which reduces the light algae needs to grow - a practical edge over translucent tanks in outdoor and sunlit installations.
Will it work for your install?
Confirm the math against your real load. Filled with water, this Norwesco vertical tank carries roughly 1,376 pounds of contents; at its full 1.5 specific gravity rating it is built to hold up to about 2,064 pounds. Use the higher number when you plan the base - a tank this size needs a flat, fully supported, load-rated pad under the entire 31 x 31-inch footprint, never a partial or point-loaded support. Run your fill scenario through the Tank Sizing Calculator and the Tank Sizing Guide to confirm 165 gallons matches your draw-down and refill cycle before you buy. For outlet placement, bulkhead and fitting thread sizes, gasket spec, and exact dimensional callouts, the technical drawing on this page is the source - confirm those details there before you plumb the tank.
Specific gravity is the number to get right
The single most common mistake on a tank this size is overlooking specific gravity. This tank is rated to 1.5 SG, which covers water (1.0 SG) with comfortable margin and most water-based stored liquids. Specific gravity is the weight of your liquid relative to water - if you store something denser than water, that 1.5 rating is your ceiling, and exceeding it stresses the tank wall over time. For plain water storage and rainwater catchment it is a non-issue; for anything heavier, match the liquid's specific gravity to the tank's 1.5 rating before you commit, and call us at 866-418-1777 if your liquid runs near or above that ceiling so we can confirm the right tank for the job.
Concrete pad and cold-climate notes
Because the loaded weight lands above a ton on a small footprint, the foundation matters. At its full 1.5-SG load, that 31 x 31-inch base (6.67 square feet) carries roughly 309 pounds per square foot - a real input for your pad design. Our guide on concrete pad sizing for above-ground polyethylene tanks walks through the ACI framework for getting that base right. If this tank feeds a rural fire-water reservoir or sits in a freeze-prone climate, the fire-water reservoir design and freeze-protection guide covers NFPA 22 sizing and cold-weather protection. Pairing storage like this into a grey-water or rainwater train is covered in our industrial water reuse tank topology and rainwater harvesting resources.
This Norwesco vertical storage tank ships LTL by freight, quoted live to your ZIP from the nearest stocking plant. It stocks and ships from plants in California, Georgia, Iowa, Minnesota, New York, Ohio, Oklahoma, Texas, Utah, and Washington - Fairfield, TX; Griffin, GA; Hanford, CA; Owego, NY; Shawnee, OK; Sheldon, IA; St. Bonifacius, MN; Tooele, UT; Washington Court House, OH; and Washougal, WA - so almost any U.S. ZIP has a plant within one freight zone, which keeps the LTL leg short and the quote competitive. Get your exact number with the Freight Cost Estimator or call us at 866-418-1777 to lock in your delivery.
