The Norwesco 2600 Gallon Multi-Use Underground Liquid Storage Tank (SKU N-43770) is a white polyethylene tank built for below-grade liquid containment, with septic, underground storage, and multi-use liquid duty all in scope. It measures 51 inches tall, 99 inches wide, and 155 inches long, giving it a 99.0 x 155.0 inch footprint you will need to plan your excavation and bedding around. This is buried-tank capacity that handles septic and underground storage without crowding a typical residential or light-commercial site.
Will it work for your application?
This tank carries a 1.9 specific gravity rating, which means the wall is engineered to hold dense liquids, not just water. Filled with water, the contents weigh 21,684 pounds; the tank is rated to carry up to 41,200 pounds of contents, so you have real headroom for heavier-than-water liquids up to that 1.9 SG ceiling. Treat those as in-service content loads for your burial planning, not shipping figures. Use them when you check your bedding, backfill, and base. If you are working through capacity and layout, run your volume through the Tank Sizing Calculator and review the Tank Sizing Guide before you dig. Because the catalog carries no fitting spec for this SKU, confirm fitting and gasket sizes against the technical drawing on this page before you order connectors, inlet, outlet, or riser hardware.
Underground installation and approvals
Because this is an underground tank, the install discipline matters as much as the tank itself - proper bedding, uniform backfill, and a level base carry the load and keep the shell true under soil pressure. If you are siting it for septic duty, confirm the approval pathway for your jurisdiction; our write-up on Norwesco IAPMO and CSA B66 septic tank approvals walks through the cross-border code scope. If you are sizing a large underground tank for rural or remote fire-water reservoir service, our guide on fire-water reservoir tank design and NFPA 22 sizing covers the reservoir math. For above-grade companion tanks or pad work elsewhere on your site, see our guide on concrete pad sizing for above-ground polyethylene tanks.
The mistake to avoid
The most common error on a tank this size is treating the SG rating as optional. The 1.9 SG figure is the maximum density the wall is built for - if your liquid is heavier than that, this tank is the wrong tool, and no amount of careful burial will compensate. Match your liquid's specific gravity against the 1.9 rating first, then confirm your excavation supports the full 41,200-pound rated content load. Get the SG and the burial base right and this tank will outlast most of what surrounds it.
This tank ships LTL freight from Norwesco's plant in St. Bonifacius, Minnesota, with freight quoted live to your ZIP - the carrier prices the empty tank, while the 21,684 and 41,200 pound figures stay reserved for your burial and load planning. Get your number now with the Freight Cost Estimator, or call 866-418-1777 and we will work out the delivery and offload details with you before you order.
