Underground Water Tanks

below ground fiberglass tanks below ground modular below ground poly


Underground water storage tanks are used for harvesting and storing rainwater underground. The ribbed design of these storage tanks make them capable of being buried underground, supporting the surrounding soil.

Underground water storage tanks have many benefits over above-ground storage tanks. For one, they’re always concealed and take up no valuable land area. Since the tanks are underground they’re not affected by freezing weather, so they can last indefinitely.

Underground water storage tanks are contained in a cool, dark environment which means they’re not as susceptible to algae and microbial growth. Due to the cleanliness of these tanks, they are the preferred storage tanks when rainwater is to be reused inside buildings.

Underground water storage tanks can store wastewater, graywater, rainwater, stormwater, and potable drinking water. In addition, tanks can also be fit with filtering components to separate oil and other contaminants — so the rain collected can be reused for landscaping and other applications.

Our two main types of underground water tanks are fibreglass and polyethylene.


Our underground fibreglass water tanks are structurally strong, corrosion-resistant, watertight, easily installed and cost-effective. Tank sizes and accessories can be customized to meet both residential and commercial design plans.

Below Ground Poly

We carry both potable and non-potable below ground poly tanks. Our potable below ground poly tanks are created using FDA approved virgin polyethylene plastic resins, which makes them suitable for the safe storage of underground drinking water.

Please see our full selection of underground water storage tanks below.

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