Rainwater retention tank
CARAT
Otto Graf
To guarantee retention of rainwater, a delayed drain is fitted in the channel with 0.05 to 2.0 l/sec. depending on the customer%u2019s specifications. In the event of heavy rainfall, the water level in the cistern rises above this level and is drained into the channel at delayed speed using a floating drain choke. This relieves the channel and the treatment works.
The water level can rise to the emergency overflow and sinks slowly back down again after the rain to the long-term max. water level.
We also construct and supply individual, special solutions.
Sizes between 2,500 %u2013 100,000 litres with corresponding retention volumes are possible.
- To retain rainwater and relieve the sewers
- For frost-proof installation in the ground








