The Rumptstad tank system is specially developed for storing clean water, polluted water, seeds, grains and granules. It consists of identical galvanised and corrugated sheets, which are joint together with bolts and nuts. The strength and rigidy of the tank system is derived from the corrugation of the sheets in combination with its round shape. Because of this special construction the sheets are lightweight and this is why our tank systems, varying in diameters from 1 to 31 metre, are very easily erected without the use of heavy lifting equipment.

Durability coating

The life span of the tank system can be substantially extended by coating the galvanised sheets with a special Durability Coating, which will be applied during the production process of the sheets. This coating also gives the tanks a professional appearance.


Most commonly used is a simple concrete floor or concrete ring. This is recommendable for less stable or rocky soil. When soil is more stabel the tank can be placed on a sand bed, sunk into the ground surface (at least 4cm).

Tank Liners (Membranes)

The metal tank systems on themselves are not watertight; a hanging synthetic water bag will take care of that. These 'membranes' are custom made to fit the tank and can be delivered in various materials, such as PVC, EPDM and HDPE. The choice of material is dependant on local circumstances, like climate and such.

Tank Covers and Roofs

Usually it is desirable to equip the tanks with a roof or cover. These covers prevent algae growth in the tanks and also protect against dust, sand, leafs and other polluting matters to be blown into the tank. In case of tanks for drinking water a special kind of roof is developed.

      The various models are:

  • Span covers (for indoor use)
  • Floating covers (for indoor and outdoor use)
  • Span roofs (for indoor and outdoor use)
  • Metal roofs (for indoor and outdoor use)
  • Balloon roofs (for indoor and outdoor use)
  • Through corrugation less weight and strong design
  • Earthquake resistance
  • Easy and fast assembly without special tools
  • World wide transport from Rotterdam port

 Rumptstad WATERstorage systems are available as:

1. Plain WATERstorage (without cover)

When water contamination is not an issue it is not particularly necessary to cover the tank.

2. WATERstorage system with span (tensioned) roofing

Span roofs are mostly used when specific requirements, like anti-algae, are needed. This kind of roofing offers a good solution for these situations. These tanks need a larger wall thickness to reinforce the panels.

3. WATERstorage system with metal roof

For applications that have even higher requirements, like lifecycle, UV resistance, proffesional appearance, the steel roof is the best solution. This kind of roofing is guaranteed to meet these needs.

4. WATERstorage system with air-pressed tank roof

This roofing solution will seal the tank completely. Mostly used on larger tanks. An airtight construction is formed by the liner and roof. This is realised by using a small fan (U=230 / P=250Watt) to keep the whole system under the right pressure. The force on the roof is absorbed by a set of tubes on the rooftop. It is a simple and efficient solution. This setting has a few requiments: it needs a concrete floor and one of our consultants needs to be present when installing the system.