Plastic underground tank series

These robust plastic storage tanks are suitable for various applications and are available in 3300l / 5000l / 7000l. Due to their low weight and the associated transport and installation without heavy equipment, they offer an alternative to the INTEWA concrete cisterns when the excavation pit is not accessible for a heavy truck. Due to the rotational sintering manufacturing process, the tanks are insensitive to pressure and impact, as well as resistant to many chemicals.

The molded dome shaft ensures frost-proof installation. An adjustable dome extension is available for deeper installation. The installed tanks can be walked on. If it is necessary to drive on the tank, the car-accessible telescopic dome can be used (ET-7000 tank only).

  • Low weight
  • Monolithic structure made of 100% recyclable PE
  • High tolerance to mechanical stress
  • Resistant to chemicals
  • Variable installation depth

BASIS storage tank

The BASIS storage tanks are equipped with three DN100 connections for inlet, overflow and supply incl. lip seals. The 3 connection positions are located on one front side of the storage tank.


MAXIMA storage tank

The MAXIMA storage tanks are pre-assembled with a PURAIN filter (incl. integrated backwater flap/small animal protection and overflow skimmer), siphon and inlet calming.


Coupling set for the connection of several underground storage tanks

  • DN 100 with 3 x lip seals
  • Incl. circular hole saw ø 127 mm with receptacle

Telescopic segment car-accessible cover

(Only in combination with ET-7000-BASIS and ET-7000-MAXIMA)

  • Adjustable from 500 to 750 mm, minus 50 mm for overlap with shaft neck (Note: Here the max. earth cover must be observed)
  • Loadable up to max. 600 kg wheel load

Telescope segment incl. walkable cover

  • Adjustable from 235 to 409 mm, minus 50 mm for overlap with shaft neck 
  • Maximum load = class A = walkable
 ET-3300-M/ BET-5000-M/ BET-7000-M/ B
Volume [liters]330050007000
Length [mm]246024582930
Width [mm]140017101980
Height without telescope segment [mm]180518102375
Height tank shoulder [mm]145017102175
Weigth [kg]118195228
MaterialPE, blackPE, blackPE, black
Inlet depth [mm]112515052065
Outlet depth [mm]1140014202040
Max. Earth cover tank shoulder [mm]8099791215
Heavy load classClass A 15 = walkableClass A 15 = walkable

600 kg wheel load with corresponding telescope dome


  • Tanks with 3.300 l are delivered with lifting platform
  • Tanks with 5.000 l can be delivered with a vehicle with lifting platform, surcharge to be inquired.
  • Tanks with 7.000 l can be delivered with a vehicle with lifting platform, surcharge to be inquired

Here you will find sample packages, instructions, technical drawings and much more.

Do you have any questions or are you interested in a non-binding offer?

We look forward to hearing from you.