The Norwesco 1250 Gallon One Compartment Septic Tank is an IAPMO-certified, single-compartment polyethylene tank built for residential and light-commercial septic systems where code requires a listed tank. At 1,250 gallons it gives installers the dimensions needed to size an excavation: 116 inches long, 55 inches wide, and 70 inches tall, for a 55.0 x 116.0-inch footprint. The shell is molded from polyethylene in Norwesco's standard yellow and ships as a Norwesco septic tank carrying the IAPMO listing that plumbing-code jurisdictions reference.
Will it work for your install?
This is a single-compartment design. Because it is a single-compartment 1,250-gallon tank, any jurisdiction or drainfield plan that requires two compartments or a separate second tank will reject it as-installed - confirm your local septic code and your designer's layout before ordering. Our guide on single compartment vs two compartment septic tanks walks through where each one fits. The IAPMO listing is the approval most US plumbing-code authorities reference; if you are installing in Canada or a CSA jurisdiction, read Norwesco IAPMO and CSA B66 septic tank approvals to confirm the certification scope that applies to you. To check that 1,250 gallons matches your household load and drainfield sizing, run the Tank Sizing Calculator or read the Tank Sizing Guide.
Weight, burial, and the mistake to avoid
Filled to capacity with water this tank weighs roughly 10,425 pounds, so the surrounding soil and bedding carry that load once it is buried - plan your excavation, bedding, and backfill accordingly. The most common mistake on a polyethylene septic tank is ignoring the manufacturer's burial and backfill procedure: poly tanks rely on proper bedding, even backfill, and water-fill-during-backfill steps to resist deformation and floating. Follow Norwesco's installation instructions and your local code to the letter, and verify the IAPMO listing satisfies your inspector before the tank goes in the ground.
Fittings and inlet/outlet connections
We do not list inlet/outlet pipe sizes or seal and gasket specs in the catalog for this tank - confirm those from the technical drawing on this page, which shows fitting and inlet/outlet locations, or call 866-418-1777 before you spec your plumbing connections. We will not invent a connection size for you; the drawing and your inspector are the authoritative sources.
Freight and how to order
This Norwesco tank ships LTL freight, quoted live to your ZIP code, from the nearest of Norwesco's plants in Lancaster, OH; Owego, NY; Tooele, UT; or Washougal, WA. Get an exact freight number with the Freight Cost Estimator, or call us at 866-418-1777 and we will route your order from the closest plant to keep freight down. The listed price is before freight; LTL is quoted separately to your delivery ZIP.
