The Norwesco 1500 Gallon Two Compartment Septic Tank is a low-profile polyethylene tank built for sites where burial depth and clearance drive the dig. At 51 inches tall over a 69 x 157 inch footprint, it sits shallow enough to clear a high water table or rocky substrate that would push a standard tall 1500-gallon tank into deeper, costlier excavation. The two-compartment design separates primary settling from clarification inside a single green poly shell, and it ships with loose plumbing so your installer can configure the inlet, outlet, and baffle connections to match the local layout. It carries IAPMO certification, the listing inspectors look for at code sign-off.
Will it work for your site
This is a 1500-gallon two-compartment unit measuring 157 inches long, 69 inches wide, and 51 inches high. Full of water it weighs 12,510 pounds, so size your bedding, backfill, and anti-flotation provisions around that loaded weight. The flip side is the condition this tank is sold for: empty, the broad 69 x 157 inch footprint and shallow 51-inch profile make it buoyancy-prone in exactly the high-water-table ground that drew you to a low-profile unit, so treat ballast and proper backfill as a direct consequence of the geometry, not an afterthought. Use our Tank Sizing Calculator and Tank Sizing Guide to confirm the 1500-gallon capacity matches your daily flow and reserve, and check your inlet and outlet inverts against the technical drawing on this page before you set the tank.
Loose plumbing: what to confirm before you order pipe
Loose plumbing means the inlet, outlet, and baffle connections are not pre-installed - they arrive for your installer to fit. Before ordering pipe, grommets, or gaskets, confirm the connection diameters and the required seal sizes at each penetration against the technical drawing on this page. The pipe-to-tank seals are part of your install scope, so do not assume standard pipe will seat without verifying the grommet and gasket sizes first; mismatched seals are the most common field failure on a loose-plumbing septic tank. Because the plumbing is field-fit, walk the connection sequence ahead of the set - our Tank Plumbing System Design walkthrough covers inlet, outlet, vent, overflow, and tie-in detailing step by step. If you plan to run an effluent filter, confirm the outlet compartment accepts your chosen filter against the same drawing.
Single vs two compartment, and the IAPMO question
A two-compartment tank does more settling work than a single-compartment unit, which is why many jurisdictions and effluent-filter requirements favor it. If you are weighing the configuration, the single compartment vs two compartment septic tank guide lays out the tradeoffs. The IAPMO certification on this tank is the listing inspectors expect, and if your project is Canadian or near the border, read our Norwesco IAPMO and CSA B66 approvals breakdown - IAPMO scope and CSA B66 are not interchangeable, and assuming they are is the most common procurement mistake on this product.
Low-profile field and procurement notes
Norwesco's low-profile septic and hauling line shares the shallow-tank handling characteristics that affect rigging, set, and transport. The Norwesco Low-Profile series field operations and procurement guide covers the practical side of receiving and placing a tank with this footprint.
This tank ships LTL freight from the Norwesco plant in Lancaster, Ohio, quoted live to your ZIP code. Get a freight quote through our Freight Cost Estimator, or call 866-418-1777 and we will quote it for you. A 157-inch, 12,510-pound-when-full tank needs adequate offload access, so confirm site reach and equipment before delivery.
