A 1000 gallon low profile two compartment septic tank for Illinois
The Norwesco 1000 gallon two compartment septic tank, part number 43541, is a green polyethylene tank 127 inches long, 60 inches wide and 51 inches tall, weighing 351 lb empty. It is made at Norwesco's Lancaster, Ohio plant and Norwesco lists its state septic approval for Illinois, so this is the low profile two compartment tank to order for an Illinois install. Low profile means the tank is long and shallow, which keeps the excavation short where a high water table, heavy clay or a shallow sewer line makes a deep hole a problem. Two compartments split the tank into a settling chamber and a polishing chamber ahead of the drainfield. Loose plumbing means the 4 inch gaskets with tee assemblies for the inlet and outlet ship with the tank for the installer to fit on site. Access is through a 20 inch gasketed manway. Norwesco lists the tank as IAPMO approved, backs it with a 5 year warranty, and sets the service limit at 130 F.
Does your county accept this tank? Call 866-418-1777 with the county and we will check before you order, or get freight to your ZIP and add it to your cart above.
Why two compartments, and why low profile
The first compartment takes the raw flow and holds most of the solids; the second takes the settled liquid and gives any remaining solids a second chance to drop before the effluent leaves. That protects the drainfield, which is the expensive part of the system and the part that fails first when solids get through. The low profile shell is for the ground where the dig is the problem: at 51 inches tall plus cover, the hole stays shallow enough that groundwater is less likely to fill it before the tank is set, the sewer line can leave the house at a modest depth and still arrive above the inlet, and the whole system can sit higher where the drainfield is near the surface. The county health department issues the permit, sets the size for your bedroom count and decides whether an effluent filter or a riser is required; call them with the part number before you order. Our note on single compartment versus two compartment septic tanks goes through the trade-offs, and Norwesco IAPMO and CSA septic tank approvals explains what the listings cover.
Openings and fittings
- Inlet. A 4 inch gasket with a tee assembly, shipped loose. The inlet tee turns the incoming flow downward so the scum layer in the first compartment stays undisturbed. The inlet sits higher than the outlet.
- Outlet. A 4 inch gasket with a tee assembly, shipped loose, in the second compartment. It draws from below the scum and above the sludge. If your code calls for an effluent filter here, tell us and we will add one to the order.
- Manway. A 20 inch gasketed manway. Both compartments need pumping, so plan access to each; if the lid will finish below grade, ask us for the riser that brings it to the surface.
- Drawing. Norwesco's drawing, linked under Technical Drawing on this page, gives the invert heights and the baffle position you need to set the pipe grades. Our inlet, outlet and vent tie-in walkthrough covers the rest of the plumbing.
Setting it
Follow Norwesco's installation instructions for this tank: they set the bedding, the backfill material and the order in which you fill the tank with water while backfilling so the walls are supported from both sides. Never backfill an empty polyethylene septic tank, and never set one where vehicles will drive. Level the bedding on both axes before the tank goes in; a long shallow tank shows an out-of-level set at the outlet invert quickly. Fit the tees, connect the pipes, fill with water to the outlet, and then call for the inspection. The low profile tank field guide covers handling a long shallow tank on site.
Related tanks
The same two compartment low profile shell for other states: the 1000 gallon low profile two compartment tank with side inlet. Single compartment versions: the 1000 gallon low profile one compartment tank and the version with a side inlet. For Florida: the 900 gallon and 1050 gallon Florida tanks.
Shipping and receiving
The tank ships LTL, 127 by 60 by 51 inches and 351 lb, from Norwesco's Lancaster, Ohio plant. The listed price is before freight; the freight cost estimator gives the lane cost to your ZIP, or request a written quote for the permit file. At the tailgate, check the part number against 43541 on the bill of lading, count both tee assemblies and the manway lid, and walk the shell for transit damage before the driver leaves.
Questions before you order? Call 866-418-1777.
Freight and documents
Ships from: Lancaster, OH. LTL freight is quoted to your ZIP with the freight cost estimator or by phone at 866-418-1777. The listed price is before freight.
Technical drawing (PDF) for Norwesco 43541.
See this tank
Product video. Watch the Norwesco 1000 Gallon Plastic Two Compartment Septic Tank with Loose Plumbing and Low Profile Design - IAPMO Certified video (63 seconds) with dimensions, fittings and shipping notes.
Ready to order?
Add it to your cart at the top of this page, get LTL freight to your ZIP, request a written quote, or call 866-418-1777. The listed price is before freight.
