The 500 Gallon Doorway Water Tank from Norwesco (SKU N-43616) is a polyethylene storage tank measuring 31" in diameter by 70" tall, molded narrow on purpose so it can pass through a standard door opening and be sited inside basements, utility rooms, pump houses, and other enclosed spaces where a wider 500-gallon vertical simply will not fit. With 500 gallons of capacity and a 1.5 specific gravity rating, it serves indoor water reserves, rainwater capture, and rural fire-water storage where access is the limiting factor.
Will it work for your application?
The defining feature is the footprint. A 31-inch listed diameter is what lets this tank go where a standard-width 500-gallon tank cannot, but treat that number as the molded nominal dimension — verify the actual outer diameter against the technical drawing on this page, since door trim and stops eat into a rough frame and the listed diameter carries no stated tolerance. Filled with water, the tank holds roughly 4,170 pounds of contents, so the floor or pad beneath it must be rated to carry that load plus the empty tank weight. The 1.5 specific gravity rating is also usable headroom: the wall is built for liquids up to 1.5 times the weight of water, giving a contents-weight ceiling near 6,255 pounds. For plain water you are well inside that margin, and if a denser liquid ever enters the picture the structure is already rated for it. To confirm this size suits your volume and refill cycle, run the numbers through our Tank Sizing Calculator and review the Tank Sizing Guide. Confirm the molded fitting locations and sizes on the technical drawing before you plan any plumbing.
How it ships
This is a freight item. It ships LTL on a pallet, quoted live to your ZIP, from whichever Norwesco plant is nearest you — this tank is molded and stocked at Griffin, GA; Hanford, CA; Lancaster, OH; Owego, NY; Shawnee, OK; St. Bonifacius, MN; and Washougal, WA. Pulling from the closest plant keeps transit time and freight cost down. Get an estimate before you order with our Freight Cost Estimator, or call 866-418-1777 for help.
The mistake to avoid
Measure the entire delivery path before you buy — not just the doorway. The narrow diameter is designed to clear a standard door, but hallways, stair turns, tight landings, and the angle a hand truck needs to negotiate a threshold can all stop a tank that would otherwise pass the frame. Walk every pinch point from the truck to the final resting spot and confirm clearance against the verified molded diameter, not the rounded listed figure. Then set the tank on a flat, fully supporting surface rated for the full 4,170-pound water weight before filling. If you are sizing a private fire-protection reserve, our guide to fire-water reservoir tank design for rural and remote sites walks through NFPA 22 sizing and cold-climate freeze protection.
For a full walkthrough of this exact tank, see the 500 Gallon Doorway Water Tank buyer's guide, or compare the smaller 250 Gallon Doorway Water Tank if your access is even tighter. Ready to move? Get your freight quote with the Freight Cost Estimator or call 866-418-1777 to lock in the nearest plant and ship date.
3 Year Warranty
