Underground Tanks & Rainwater Tanks - for underground installation

We offer high quality, rotationally moulded plastic (polyethylene - LLDPE) underground tanks in various sizes with capacities from 1,000 to 10,000 litres. Our underground tanks are mainly used as classic underground rainwater tanks, as cisterns in the commercial sector or in private homes. Use our robust and dimensionally stable rainwater tanks for garden irrigation, as a water treatment system for your home and garden or as a wastewater collection tank. Underground rainwater tanks make environmental and economic sense, saving up to 50% of potable water, conserving groundwater supplies and reducing pressure on sewage treatment plants. Made from 100% recyclable polyethylene, the tanks are durable and lightweight. This makes them easy to handle during transport and installation.

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  1. 10.000 Litre Round, horizontal Underground tanks made from green Polyethylen with large lid
    -15%
    10.000 Litre Round, Horizontal Underground Tankl – (RPO-Series)
    At 10/16/25
    Special Price €5,056.49 €4,249.15 was €4,999.00 15% Discount
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Underground Tanks for rainwater utilisation - perfect for home and garden

Using free rainwater in your garden and home will save you money and make you more independent. After all, drinking water is not always needed for every application. The permanent availability of water no longer seems to be a given for the future. This is a global problem that affects us all due to climate change and demographic trends. Even in Europe, some regions are already experiencing water shortages. Rainwater harvesting with an Underground Tank is therefore a good way to reduce drinking water consumption. In contrast to storing rainwater above ground, water in an underground tank stays cool and fresh for longer, as underground storage is associated with lower temperatures and fewer large temperature fluctuations. 

Rainwater can be used wherever drinking water quality is not required.

  • Garden irrigation
  • Toilet flushing
  • Car washing, cleaning

Rainwater should not be used where the human body comes into direct contact with the water, particularly for personal hygiene, preparing food and drink and washing dishes.


Features of Underground Tanks in horizontal & round design

  • Volume: 1,000-10,000 litres
  • Horizontal, round versions
  • Diameter: 92-213 cm
  • Rotationally moulded from a single cast - manufactured without weld seams
  • Material: LLDPE (polyethylene), UV-stabilised, food-safe
  • Crane loops for safe transport and easy relocation
  • Large manhole cover openings (30-70cm)
  • Top and bottom connection panels/flat spots for inlet and outlet
  • Matching PP Tank Connection Sets - can be installed completely from the outside
  • Individual Push-In BSP Fittings / connections can be installed in various inch sizes

As we do not offer an installation service, we are currently offering a 15% discount on the purchase of our Underground Tanks.


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