The Norwesco 1500 Gallon One Compartment Septic Tank pairs a low-profile body with loose plumbing so installers can set tank-to-grade and tie in inlet, outlet, and vent on site. At 51 inches tall, 69 inches wide, and 157 inches long, it drops into a shallower excavation than a tall vertical septic tank of the same capacity, which matters where you hit a high water table, rock, or a buried utility before you can dig deep. The body is molded polyethylene in green, holds a true 1500 gallons, and carries a single compartment. Filled to capacity with water it weighs about 12,510 pounds over a 69 by 157 inch footprint, so the excavation bed and the freight both have to account for that load up front.
Will it work for your install
This is a single-compartment, loose-plumbing tank, meaning the inlet and outlet plumbing ships separate for you to set and seal during installation rather than arriving factory-plumbed. Because the plumbing is loose, fitting and gasket sizing is set in the field, so confirm your required inlet, outlet, and vent diameters against your drain-field plan before you order bulkhead fittings and gaskets. The footprint is 69 by 157 inches, so check your trench length and the setback to your drain field before you commit. The shell carries no specific-gravity rating because it is built for septic and wastewater, not heavy chemical service. With about 12,510 pounds of full-water weight, the excavation bed has to be level, compacted, and free of point loads; back-fill evenly around the low-profile sidewalls to avoid distorting the body. If you are still weighing this against a taller body, the Tank Sizing Calculator and our Tank Sizing Guide will help you match capacity to your daily flow and site depth.
Plumbing and code approval
Because the plumbing is loose, your inlet and outlet invert heights, the vent, and any overflow tie-in are set in the field, so plan those elevations before the tank goes in the hole. Our walkthrough on tank plumbing system design: inlet, outlet, and vent covers how to lay out those tie-ins. This is a one-compartment design, and many jurisdictions require a two-compartment tank or a downstream effluent filter for certain flows, so verify the single-compartment configuration against your local code before purchase. Septic approval is jurisdiction-specific; if you are installing in Canada or near the border, read our guide to Norwesco IAPMO and CSA B66 septic tank approvals to confirm what your local code accepts. For field-handling notes on the low-profile series, see our Norwesco low-profile series field operations and procurement guide, and always clear the model with your county or health authority.
The mistake to avoid
The most common error on a tank this size is treating loose plumbing as factory plumbing. Nothing is sealed for you at the factory, so the watertightness of every penetration depends on how you set and gasket the fittings in the field; a rushed inlet seal is the usual cause of a failed inspection. Set the tank dead level, confirm your invert heights against your drain field before back-filling, and pressure-check the connections.
This 1500-gallon low-profile septic tank ships LTL freight from the Norwesco plant in Griffin, GA, with the rate quoted live to your ZIP code through our Freight Cost Estimator. Refer to the technical drawing on this page for invert and fitting locations, and call 866-418-1777 if you want help confirming sizing or scheduling delivery.
