Stormwater Treatment

Ecotechnic Stormwater Treatment

Environmentally friendly treatment


The sedimentation plant unerringly removes the filterable substances (TSS) from the stormwater runoff. In this way, it protects water bodies and infiltration systems.

First, the water is introduced tangentially into the sedimentation plant in the middle of the system. Sedimentation of solids now takes place through the so-called teacup effect. The solids sink into the sludge trap at the bottom, which is hydraulically separated from the treatment chamber by a grate and flow breaker so that remobilization of settled particles does not occur during heavy rainfall.

In the outer ring of the sedimentation plant, the water flows evenly upwards. A weir ensures that there are no short-circuit flows in the plant and that the flow is as homogeneous as possible. The water then flows through the weir into the drain. Light substances such as oils or pollen are effectively retained, as they cannot pass under the separator wall. The sedimentation system has no height offset between inlet and outlet. The system cannot block. The system can be used on all surfaces, from roofs to traffic areas and industrial sites. The cleaning capacity is designed in such a way that the requirements of DWA M 153 and A 102 are reliably met.

Decentralized sedimentation plants are becoming increasingly important in the context of precipitation water treatment.

Operating principle

  1. The water flows in tangentially in the center of the hydrodynamic separator.
  2. Solids settle to the bottom, floating solids remain on the water surface.
  3. Solids are collected in the sludge trap, which is hydraulically separated from the treatment chamber by flow breakers and a grate, so that remobilization does not occur.
  4. The water rises evenly on the side walls.
  5. The purified water is collected in an annular space by a weir and then transported to the outlet.
  6. Outlet.


Approvals and Certificates

  • Effluent value according to DWAM 153 D = 0,2 - 0,35 (field D25) for connectable surfaces according to table, rkrit = r(15,1), here simplified with 150 l/(s·ha)
  • Effluent value according to DWAM 153 D = 0,50 (field D24)  for connectable surfaces according to table, r krit = 45 l/(s·ha)
  • Tested in the laboratory in accordance with the requirements of DWAA 102 with AFS63 (retention of AFS63 > 55 % for surfaces of category 2, >70 % for surfaces of category 3)
  • Laboratory testing according to the NRW separation decree with AFS200 according to the modified DIBt procedure
  • Tested according to American NJDEP protocol