Are Polyethylene Tanks Suitable as Sewage Tanks?
Short answer: yes. Polyethylene's high chemical resistance and durability make it a solid material for dedicated sewage and industrial tanks too, not just drinking water storage. That's part of why Haggan tanks also get used for chemical and petroleum storage in some industrial settings.
Difference in Material and Design
Drinking water tanks are made from certified food-grade virgin polyethylene, with a smooth interior that resists sediment buildup. Sewage tanks are engineered for entirely different organic and chemical content, often with a different design and material unsuited to drinking water health standards.
Why Combining the Two Uses Is Prohibited
Even a thorough cleaning won't get every trace of biological contamination out of a tank that's held sewage. That residue is a real health risk once the same tank goes back to holding drinking water. It's why we, and honestly any manufacturer worth trusting, tell customers flatly: keep two separate tanks.
The Bottom Line
Keep them separate, full stop. And for the drinking water side, get a certified virgin polyethylene tank with a real warranty behind it. That's the whole game, really.
