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NEW FROM RAINWATER MANAGEMENT! Rainwater Management is proud to unveil our new ETV approved Oil Grit Separators (OGS) that we call the RWM-DM and RWM-DM-OS units. We have spent 18 months testing and developing the system to meet the latest ETV Canada Procedure for Testing Oil-Grit separators (ISO 14034) testing requirements. Contact us to discuss which OGS is best suited for your application.

The ETV Canada test protocol is the new standard that people refer to in Canada for OGS systems. We are the first to meet the new testing and reporting requirement. The latest requirement limits the inlet pipe size to ¼ the manhole diameter and limits the length to 3 times the pipe diameter. The old protocol did not limit inlet pipe size and allowed the inlet pipe length to be 4 pipe diameters. The new ETV requirement includes the disclosure of the quantity of sediment settled in the inlet pipe during testing.

We tested OGS configurations mimicking competitor systems and found they would remove over 85% of the sediment captured in the upstream pipe. This means that the OGS units that do this and are installed in the field will be trapping the pollutants in the upstream piping system rather than the OGS manhole. RWM targeted zero pipe settling so that we trap the sediment in the OGS manhole as it should be. ALL OGS systems tested prior to the RWM-DM have included the sediment settled in the inlet pipe in their TSS removal calculations. Most of the ETV approved products are specifically designed to enhance the pipe settling as part of their testing to make their performance look better than it is.

The RWM-DM-OS unit has a lower weir height then the RWM-DM and specifically targets oil spill capture and retention while still removing sediment.

RWM-DM System Benefits

  • Simple installation and cleanout
  • ETV verified technology
  • Cost effectively removes a wide range of pollutants
  • Isolated sump eliminates captured sediment washout
  • Customizable / flexible design overcomes multiple site constraints and accommodates a wide range of treatment options
  • RWM-DM-OS unit has 99.9% oil capture and retention

The concrete portions of our OGS units are supplied by local pre-casters in the Vancouver area, Calgary, and Saskatchewan. Manitoba is serviced by Saskatchewan.

Also Available


RWM Ultra