Flow regulator type SDSTo avoid hydraulic overloads of sewerage and waste water treatment facilities; CSO systems, and storm water detention tanks must be created. These systems will store excess flow during storm events and regulate the onward flow to treatment. The pass forward flow rate needs to be carefully controlled to avoid hydraulic overload of the downstream system. It is important that the flow form these systems remains constant irrespective of the operating head.

Short function description

In dry weather the regulator is completely open. If the water-level exceeds a certain height during storm conditions the regulator will be activated. The electrical drive is actuated and closes the regulator mechanism until the correct control plate position is reached. The electronic controller permanently compares the measured water level with the programmed set value. The regulation process continues until the top water level in the basin drops below the pre-set level. If this is the case, the regulator is completely opened automatically so that full flushing is available.

If during the regulation process a blockage occurs, the flow rate is inevitably reduced. This leads to an automatic actuation of the control plate and if required the full opening of the regulator. After the flushing of the orifice and instant increase in the flow rate the penstock is returned to its regulating position. With an underwater blockage the water-level difference is recalculated and the desired flow rate regulated.

  • Measurement section does not require a siphon
  • High accuracy even with partial filling
  • Incremental adjustment of flow rate
  • Optional remote operation
  • Automatic de-blocking
  • Can also regulate during downstream flooding
  • Active regulator in accordance with ATV A111
  • High separation vertical Q/H characteristic


The Storm Water-Flow Limiter Type SDS can be manufactured in the following nominal sizes DN 100 up to DN 1000 for desired flow rates from 2 l/s to 2400 l/s. Other nominal sizes and flow rates available upon request.