The Norwesco 6500 Gallon Black Heavy Duty Vertical Storage Tank is a large-format polyethylene vertical storage tank built for bulk water and high-density liquid service. It stands 147 inches tall on a 120-by-120-inch footprint and carries a 1.9 specific gravity rating, which is what makes the "heavy duty" designation real rather than marketing: the wall is engineered to hold contents far denser than water. Whether you are sizing a fire-water reservoir, a rural water cache, or an industrial process buffer, this is a large-format black-resin vertical tank built for outdoor installs.
Will it work for your application?
The tank holds 6,500 gallons. Full of water, the contents alone weigh 54,210 pounds, and the 1.9 SG rating means it is engineered for up to 102,999 pounds of rated contents. That headroom is the point of the heavy-duty wall: you can store liquids heavier than water without exceeding the tank's design limits. The 120-by-120-inch footprint is the number that drives your pad, and a tank this size needs a properly engineered foundation, so work through our concrete pad sizing guide before you set it. The pad has to carry the full loaded weight, not the empty tank. If you are still deciding on capacity, the Tank Sizing Calculator and Tank Sizing Guide will help you match volume to your draw rate and refill cycle.
Common applications and sizing notes
At 6,500 gallons, this Norwesco vertical storage tank is frequently specified for private fire-protection reservoirs on rural and remote sites, where a single large cache backs the suppression system. If that is your use case, our fire-water reservoir design guide covers both NFPA 22 sizing discipline and the freeze-protection engineering that matters with a 147-inch column of water in a black tank on a cold-climate site. For reuse and aggregation projects, where grey water, rainwater, or HVAC condensate feeds a banded storage train, the industrial water reuse topology guide shows how a tank this size fits the architecture.
The mistakes to avoid
The biggest error on a tank this large is undersizing the foundation. The 102,999-pound max rated weight is not theoretical; if you fill this tank with a liquid near its 1.9 SG ceiling, that is the load your pad and soil have to carry, year-round. Pour and cure a pad rated for the full loaded weight before delivery, and confirm your site can handle the 120-by-120-inch footprint with proper drainage and frost considerations. Second, treat the SG rating as a density limit, not a chemical-resistance rating: the 1.9 figure describes how dense a liquid the wall tolerates, not what it resists chemically, so if you intend to store anything other than water, verify polyethylene compatibility for your specific liquid first. Third, this listing does not specify fitting sizes or locations. Confirm your fill, outlet, vent, and manway configuration from the technical drawing on this page or by phone before you order valves, bulkhead fittings, or gaskets, and remember that gasket and seal material is a separate compatibility decision from the tank wall.
This tank ships LTL freight from the Norwesco plant in Fairfield, Texas, quoted live to your ZIP code. Because of its size and the 54,210-pound loaded water weight, delivery requires confirmed site access for offload, so plan turning radius and equipment in advance. Get an exact freight number with our Freight Cost Estimator, or call us at 866-418-1777 and we will quote the logistics and confirm site-access requirements for a tank this large.
