RainJets hydroejector - cleaning  tanks - storage of stormwater or wastewater

The RainJet is a hydroejector designed to automatically clean tanks used for the temporary storage of stormwater or wastewater so that odour problems are avoided and storage capacity is maintained.

The RainJet continues flushing until the tank is completely empty and all the contents have been pumped into the sewer system. It uses the water already in the tank and hence does not need an external source of fresh water.

The RainJet is made either as a water/water (WW) or water/air (WA) ejector:

  • RainJet WW with greater flow for cleaning wider tanks
  • RainJet WA with jet that reaches further and is mixed with air.

The RainJet is made entirely of stainless steel of AISI 304/DIN1.4301 or AISI 316/DIN 1.4401, and is coupled to a wastewater pump of the SE or S type.


No matter what the size and layout, a customised solution of one or more RainJets can easily be designed to clean detention, equalisation or stormwater tanks used for the storage of excess water in order to minimise the risks of:

  • Flooding or pollution of receiving waters if capacity of the sewer system is exceeded
  • Damage of biological processes at the WWTP if untreated industrial process water arrives
  • Disruption of purification processes at the WWTP due to hydraulic overload.

Features and benefits

  • Available as water/water or water/air ejectors
  • RainJet WA available with a 2nd stage for extra thrust
  • Made completely in stainless steel for strength
  • Available with standard pumps in many motor sizes
  • Fitted with sturdy submersible wastewater pump of the SE or S type
  • Suits tanks of different sizes, depths and shapes
  • Mixing and cleaning handled by same the unit
  • Large free passage – no clogging
  • Fixed or auto-coupling connections suiting every type of installation
  • Pumps on auto-coupling to make maintenance easier and more flexible.