Detention cistern for rainwater detention and sewer relief

  • A detention cistern retains the rainwater and drains it into the sewer at a delayed speed.
  • GRAF cistern for rainwater detention and sewer relief.
  • To guarantee retention of rainwater, a delayed drain is fitted in the sewer with a delay of 0.05 to 16 l/sec. depending on the customer’s specifications.
  • In the event of heavy rainfall, the water level in the cistern rises above this level and is drained into the sewer at a delayed speed using a floating drain choke. This relieves the sewer and the treatment works. The water level can rise to the emergency overflow and sink slowly back down again after the rain.
  • Sizes between 1,500 – 7,500 l with corresponding retention volumes are possible. 
  • We also construct and supply individual, special solutions.

Sizing

Volume [l]Length [mm]Width [mm]Height [mm]Weight [kg]Retention volume [l]order no.add to enquiry
75003600225015653607500390305
50002890230013152405000390302
30002450210010501703000390301
1500210012501015801500390300

calculated size Request for information

Technical details

Installation

max. earth covering [mm] (without groundwater, vehicle loading) 1200

Accessibility

Earth covering with loading capacity [mm] 700 - 1000
max. axle load [t] 2.2
max. vehicle weight [t] 3,5

Groundwater installation

Earth covering with groundwater installation [mm] 700 - 1200
Eintauchtiefe ins Grundwasser bis Tankschulter

General

Warranty period (years) 30

Accessory