The Norwesco 1250 Gallon One Compartment Septic Tank is a low-profile, IAPMO-certified polyethylene tank built for septic installs where burial depth and clearance are tight. At 51 inches tall on a 60 x 157 inch footprint, it holds 1,250 gallons in a single green-polyethylene compartment while sitting low enough to ease excavation in high-water-table or shallow-cover sites. It ships with loose plumbing, so the outlet tee and fittings travel with the tank for field assembly. This is a "norwesco low profile" septic tank for installers who need a code-recognized one-compartment vessel without a deep dig.
Will it work for your install?
This is a one-compartment septic tank rated at 1,250 gallons in green polyethylene. The technical drawing on this page calls out the outlet tee at the top of the outlet (1 inch reference) and the outlet connection itself; the rest of the plumbing arrives loose for you to set during installation. The pack does not specify inlet/outlet grommet sizes or gasket types beyond that 1-inch outlet-tee reference, so confirm grommet and gasket sizing against your actual inlet and outlet pipe before you order pipe, and verify your inlet and outlet inverts against your drain-field design before backfill. For sizing against household fixture units and daily flow, run the Tank Sizing Calculator and review the Tank Sizing Guide. Our tank plumbing system design walkthrough covers inlet, outlet, vent, and tie-in detailing so the loose plumbing goes in clean.
Certification and code
This tank is IAPMO certified, which matters because many jurisdictions accept IAPMO listing as the basis for plumbing-code approval of plastic septic tanks. Certification scope and acceptance vary by state and county, and Canadian installs reference CSA standards rather than US plumbing codes, so before you specify or bury this tank, verify it is accepted by your local health department or building authority. Our guide on Norwesco IAPMO and CSA B66 septic tank approvals breaks down the cross-border scope so you do not assume a US listing carries into Canada or vice versa. For the broader low-profile Norwesco lineup and field handling, see the low-profile series field operations and procurement guide.
The mistake to avoid
The most common error on a low-profile septic tank is treating it like a deeper, taller tank during installation. The 51-inch height gives you shallow cover, which is the point, but the wide 60 x 157 inch footprint also means a large uplift area: a partially empty tank in saturated soil can float if it is not properly ballasted and bedded. That same footprint drives both your excavation cost and your ballast load, so plan for it. Filled with water at full capacity the tank carries roughly 10,425 pounds, but the buoyancy risk is highest when the tank is empty in a wet trench. Set the tank level, follow Norwesco's burial and backfill instructions, confirm your invert elevations work with only 51 inches of tank depth, and because the plumbing ships loose, double-check that the outlet tee orientation matches your field layout before backfilling.
This tank ships LTL freight on a pallet, quoted live to your ZIP from the nearest Norwesco plant among Lancaster, OH; Shawnee, OK; St. Bonifacius, MN; Tooele, UT; and Washougal, WA. Origin proximity is the single biggest freight driver on a tank this large and light, so a buyer in Texas or California will see a very different quote than one in the upper Midwest. Get a freight quote with the Freight Cost Estimator, or call us at 866-418-1777 to confirm certification acceptance for your county and lock in your freight quote.
