Norwesco
Rotationally molded, one-piece septic, cistern, holding, and vertical storage tanks — a TankHolding brand, since 1980.
What LibertyCES specifies from Norwesco

Rotationally molded, one-piece, seamless construction, 200–10,000 gal. Legacy ribbed tanks carry a real hard constraint: must be kept full (or 1/4 full) at all times.

25–15,500 gal. Black/Dark Green line is explicitly rated water-only — not for chemicals, fertilizers, or any other product.
Norwesco — Real Catalog Spec Data
| Product Line | Model | Category | Material | Size / Capacity | Temp Rating |
|---|---|---|---|---|---|
| Low Profile Septic Tanks | Low Profile Septic Tank | Wastewater Tank | rotomolded polyethylene | 500-1500 gal | single or double compartment |
| Bruiser Septic Tanks | Bruiser Septic Tank | Wastewater Tank | rotomolded polyethylene | 1000-1500 gal | multi-use: septic, holding, pump chamber, or potable water single-compartment |
| Legacy Septic Tanks | Legacy Septic Tank (ribbed) | Wastewater Tank | rotomolded polyethylene, ribbed | 500-1500 gal | not for pump tank use, must stay full at all times |
| Spherical Pump Tanks | Spherical Pump Tank | Wastewater Tank | rotomolded polyethylene | 200-525 gal | may remain in ground empty |
| Holding Tanks | Holding Tank | Storage Tank | FDA-compliant polyethylene | 2000-10000 gal | n/a |
| Low Profile Cistern Tanks | Low Profile Cistern Tank | Storage Tank | FDA-compliant polyethylene | 575-1750 gal | ANSI/NSF Std 61 certified where applicable |
| Legacy Cistern Tanks | Legacy Cistern Tank (ribbed) | Storage Tank | polyethylene, ribbed | 600-1700 gal | must stay 1/4 full at all times (600gal+) |
| Spherical Cistern Tanks | Spherical Cistern Tank | Storage Tank | polyethylene | 225-550 gal | n/a |
| Flat Bottom Utility Tanks | Flat Bottom Utility Tanks | Storage Tank | polyethylene | 200-500 gal | n/a |
| Loaf Tanks | Loaf Tanks | Storage Tank | polyethylene | 50-1050 gal | n/a |
| Pickup Truck Tanks | Pickup Truck Tanks | Storage Tank | polyethylene | 210, 325, 425 gal | installed bulkhead fitting standard |
| Horizontal Leg Tanks | Horizontal Leg Tanks | Storage Tank | polyethylene | 35-525 gal | 525gal requires full-length support |
| Elliptical Leg Tanks | Elliptical Leg Tanks | Storage Tank | polyethylene | 3135 gal | requires full-length bottom support + 4 bands |
| Freestanding Tanks | Freestanding Tanks | Storage Tank | polyethylene | 100-1000 gal | sized to fit through conventional doorway |
| Water Hauling Tanks | Water Hauling Tanks | Storage Tank | polyethylene | 1250-2400 gal | low profile for height-limited placement |
Sourced from Norwesco's own catalog documentation.
Related Manufacturers & Products
Frequently Asked Questions
Can Norwesco Black/Dark Green vertical tanks store chemicals?
No — per Norwesco's own catalog, verbatim: these tanks "are rated at 8 pounds per gallon, which means that they are for WATER STORAGE ONLY! They should not be used for chemicals, fertilizers or any other product." The dark color is specifically for limiting light penetration to reduce algae growth in water storage, not chemical compatibility.
What is the install constraint on Norwesco Legacy septic and cistern tanks?
Legacy (ribbed) septic tanks must be kept full at all times, and Legacy cistern tanks 600 gallons and larger must be kept at least 1/4 full at all times — the rib design relies on internal counter-pressure against external soil pressure, and getting this wrong can cause tank collapse.
When would I choose Viton over EPDM for a Norwesco bulkhead fitting?
Norwesco offers Viton as a standard option specifically "when EPDM may not be suitable for your application" — relevant for strong oxidizers like sodium hypochlorite, where EPDM has known compatibility limits versus fluoroelastomers.
Get the right tank family and fitting material for your application
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