Onsite Wastewater Tanks

Choosing fiberglass tanks translates into ongoing savings
Xerxes corrosion-resistant fiberglass tanks offer numerous material and design advantages that make them reliable, cost-effective wastewater storage tanks. Secure storage of corrosive wastewater is essential in both onsite and municipal applications no matter how small or large the quantity. The smooth, rounded walls of our cylindrical tanks don’t trap debris like tanks with corners, making them easy to clean. Since fiberglass is inherently corrosion-resistant, inside and out, our tanks don’t need added liners to protective against corrosive wastewater. The result is a reliable tank with ongoing cost savings from the regular inspection and maintenance required for tanks of other materials.
Being compatible with treatment systems is part of our value
Our sales and engineering teams work directly with treatment system packagers to ensure that our wastewater tanks are designed and manufactured to meet the treatment configurations our customers need:
- Primary treatment
- Secondary treatment
- Aerobic treatment
- Fixed-film media
- Recirculation
- Dosing
Why choose a Xerxes wastewater tank?
- Single-tank capacities up to 60,000 gallons
- Tank diameters up to 12 feet
- Designed to withstand H-20 and HS-20 axle loads
- Standard and customized accessories
- Easy to ship, install and maintain
Xerxes tanks meet – or exceed – industry standards
They can be manufactured to comply with the IAPMO/ANSI Z1000 standard
Success Stories

RV Park - Oregon, US
Fiberglass tank provides
long-term water conservation
When the owners of an RV park in Oregon upgraded their septic system, they wanted to come up with a solution that added to their energy-generating solar panels. With a maximum 5,000-gallon draw of well water per day, they needed another water source for irrigation. The park owner installed a patented natural wastewater system, using willow and poplar tree roots and bacteria to break down and neutralize pollutants, so that the treated wastewater could be reused for landscaping. As part of this innovative system, this project needed a tank that could be easily customized and installed in a tight excavation footprint. Xerxes provided a three-compartment 25,000-gallon tank, with baffles separating the chambers used for each phase of the wastewater treatment process. Our tank was the perfect underground storage option for this innovative wastewater system that created long-term conservation of both water and energy.
Mining - Alaska, US
Helping protect water source for an Indigenous community
A wastewater tank that traveled nearly 2,000 miles – by air, sea and road – to an Arctic Circle zinc mine is a prime example of how easy it is to ship and install Xerxes tanks. It’s also proof that our highly engineered tanks can be installed in the most extreme climates. While an unusual project – installed in an aboveground shipping container because the permafrost precludes underground installation – it also shows our tank’s adaptability. The tank is part of the mine’s treatment system, with strict guidelines so wastewater discharge doesn’t endanger a nearby village. Beyond needing an easy-to-transport tank, the land and mine owners, the Iñupiat people of northwest Alaska, required a customizable tank resistant to harmful chemicals. The majority of the mine’s workforce are Indigenous people. This installation is a good example of how adaptable our fiberglass tanks are.
