The Norwesco 1250 Gallon Two Compartment Septic Tank is a low-profile polyethylene septic tank built for installs where burial depth is tight and a tall single-compartment tank will not work. It lists at 1,250 gallons split across two compartments, ships with loose plumbing for field assembly, and measures 157 inches long by 60 inches wide and just 51 inches tall - a long, flat footprint of 60.0 x 157.0 inches. It is the SI-version of the Norwesco low-profile two-compartment design, in green polyethylene.
Will this Norwesco low-profile septic tank work for my site?
The two-compartment layout splits the tank into two chambers inside one shell. At 51 inches of height, this is the tank to reach for when a conventional vertical septic tank sits too deep for your water table or excavation. This is a non-pressurized, gravity-flow septic vessel for domestic wastewater - it carries no elevated specific-gravity rating because none applies to standard gravity septic service. Full, the tank holds roughly 10,425 pounds of water at capacity; that figure is water weight only and excludes the empty shell and any accumulated solids, so size your excavation, bedding, and any required anti-flotation measures for the loaded tank, not the empty one. If you are weighing one tank versus two, our guide on single compartment vs two compartment septic tanks walks through the trade-offs, and the Tank Sizing Calculator and Tank Sizing Guide help you confirm the 1,250-gallon size against your daily flow.
Plumbing and approvals
Because the plumbing arrives loose, the exact components and their inlet, outlet, and tie-in locations are shown on the technical drawing on this page - review it and assemble the plumbing before you set and backfill the tank. Our tank plumbing system design walkthrough covers inlet, outlet, vent, and overflow tie-ins step by step. Septic tank approval is jurisdiction-specific: confirm what your local health department or plumbing authority will accept before ordering. For cross-border and code-scope questions, our overview of Norwesco IAPMO and CSA B66 septic tank approvals explains how US plumbing codes and Canadian approvals differ. For more on this low-profile family, see the Norwesco low-profile series field operations and procurement guide.
The mistake to avoid
The most common error on a low-profile tank this large is treating it like a freestanding cistern at install. A long, shallow tank with a 157-inch footprint is more sensitive to uneven bedding and to flotation in high-water-table sites than a compact vertical tank - get the bedding flat and full-contact, and follow Norwesco's installation requirements for backfill and any ballast. Second, do not assume local acceptance - this is a septic tank, not a potable water tank, and approval varies by jurisdiction, so verify before you buy.
This tank ships LTL freight from Owego, NY, with the rate quoted live to your ZIP. Get your number from the Freight Cost Estimator, or call us at 866-418-1777 and we will line up the freight and answer any sizing or plumbing questions on your low-profile Norwesco septic tank.
