Flat Tank for Rainwater

  • Shallow installation depth
  • Minimal excavation work
  • Light weight
  • Can be installed by hand
  • Easy to combine with the modular soakaway crate
  • Seamless one-piece unit
WISY flat tank, 1,500 litres capacity. Optionally with rainwater filter LineAr 100 K.


The WISY flat tank is the perfect product for storing up to 1,500 or 3,000 litres of rainwater underground. Thanks to its very light weight and shallow installation depth, the tank is easy for anyone to handle. It can be installed without the need for an excavator or digger.

WISY flat tank with basic equipment

  • With flange connection and lid

Additional included in the flat tank with complete equipment

  • Access shaft extension tube with pedestrian-duty cover
  • LineAr 100 rainwater filter with body made of polypropylene, filter insert made of stainless steel
  • Smoothing inlet made of stainles steel
  • Including piping
  • (weight 76 kg)
WISY-Flachtank 1.500 l
Außenmaße WISY-Flachtank 1.500 l

Optional access shaft extension tube:

Access shaft extension tube for self cutting 9, 15, 21 or maximum 27 cm in additional height.

Access shaft extension tube for WISY flat tank

Technical Data

1,500 Litres Flat Tank 3,000 Litres Flat Tank
Volume: 1,500 l 3,000 l
Scope of application: below ground below ground
Dimensions: 1866 x 1500 x 990 mm
In- and Outlet diameter: 110 mm 110 mm
Top hole, diameter: 470 mm
Weight basic equipment: 70 kg 150 kg
Weight complete equipment: 76 kg 156 kg
Maximum load: pedestrian duty pedestrian duty

Item number

1,500 l flat tank, basic equipment FL 1500
1,500 l flat tank, complete equipment FL 1550
3,000 l flat tank, basic equipment FL 3000
3,000 l flat tank, complete equipment FL 3050
Access shaft extension tube (9, 15, 21 or 27 cm additional height, for self cutting) FD 1010