Norwesco 1000 Gallon Plastic Multi-Use Underground Liquid Storage Tank IAPMO Approved

Septic, pump tank or cistern

Buried, this tank does three jobs. As a septic tank it takes the house drain through the inlet tee and sends settled effluent out through the outlet tee to the drainfield. As a pump or dosing tank it holds effluent until a pump lifts it to a mound or a pressure field. As a cistern it stores rainwater or hauled water for irrigation, stock or fire protection; 1000 gallons of water weighs 8340 lb, so plan the pad and the backfill for that load. Where the water is for drinking, tell us before you order and we will confirm the right tank. For a fire reserve, our guide to fire water reservoir design for rural sites covers how buried polyethylene fits the private fire protection stack. Approvals are the first question with any septic tank: Norwesco's IAPMO listing and the state list above are what the health department will ask for, and our note on Norwesco IAPMO and CSA B66 septic approvals explains what each listing covers. If your state is not on the list, call us; the same shell is sold under other part numbers with other state approvals.

Openings, fittings and risers

1. Inlet and outlet. A 4 inch adapter with a PVC tee assembly at each end, ready for 4 inch drain pipe. The tee keeps floating solids away from the outlet; it goes in before the first drop of effluent.
2. Manway. One 20 inch gasketed manway with a 20 inch lid. Gasketed matters below grade: it keeps groundwater out and odour in.
3. Risers to grade. Norwesco's optional risers and extensions for this tank, two of each for the two manholes, are the N-63514 6 inch extension, N-62397 15 inch extension, N-62396 24 inch extension, N-62395 25 inch riser with 12 inch lid and N-63830 36 inch riser with 6 inch lid. Measure from the top of the tank to finished grade before you order so the lid lands at the surface, not under the sod.
4. Drawing. Norwesco's drawing for this tank, linked under Technical Drawing on this page, gives the invert heights of the inlet and outlet and the manway positions for setting the excavation.

The same tank for other states

Norwesco builds this 1000 gallon shell at several plants under different part numbers, each with its own state approval list: the 1000 gallon multi-use tank 41734, the 1000 gallon multi-use tank 41735 and the 1000 gallon multi-use tank with gaskets, tees and two manhole covers. One size up is the 1250 gallon multi-use underground tank. Use the tank sizing calculator and tank sizing guide if the code in your county sets the size by bedrooms or by daily flow.

Shipping, receiving and setting

The tank ships LTL from Norwesco's Hanford, California plant, 102 by 60 by 63 inches on the truck at 388 lb. The listed price is before freight; the freight cost estimator gives the lane cost to your ZIP. Have the hole ready or a flat place to stage it, because a 388 lb tank is easy to move empty and easy to damage if it is dragged over rock. At the tailgate, check 41820 on the bill of lading against the moulded part number, look over the tees and the manway gasket, and walk the shell for transit cracks before you sign. Set it on the bedding Norwesco's installation instructions call for, fill it with water as you backfill so the walls stay round, and keep vehicles off the area above it.

Questions before you order? Call 866-418-1777 with the permit in hand.