Deflector Trap

Deflector Trap

The Deflector trap uses strategically placed horizintal deflectors , placed at varying heights, to guide the polluants into the containment bay . We use the available energy in the water flow to transport the Gross Pollutants into the containment bay where it can drain dry upon the abatement of the flow. This is the basis of our catch phrase

Guiding the Gross Pollutants  from the mainstream flow into the containment bay is how we achieve "Dry Rubbish".

Guiding the Gross Pollutants  from the mainsteam into the containment bay is how we achieve " Dry Rubbish ".

Where Used

The Deflector trap is used in  High Volume and Low Velocity sites where there is minimal headloss  available.

Site Requirements

Target Pollutant Class

The Deflector trap is targeted at capturing the Gross Pollutant class of pollutants; however history shows they capture a varying amount of sedimentsand oils as well.

Water Sources / Velocity

The Deflector trap is primarily used for sites with low velocity flow and is suitable for treating the following water sources:

  • Large Pipes
  • Channels
  • Culverts
  • V-Drains
  • Natural Flows

See our Dual Vane trap for medium to high velocities in a similiar configuration.


The Deflector trap is suitable for the flatter grade . Please note while we can cater for high grades some design modification may be required.

Treatable Flow

The Deflector trap is suitable for treating flows from as low as a  3 month ARI  up to a  100 year ARI .

We don't treat the "first flush", we treat the whole flow for the duration of the event.



The size of the Dual Vane Trap is dependent on the:

  • Cross Sectional area of the Water Source, 
  • Velocity, 
  • Catchment type and size,
  • Required Treatable Flow 

T o give you an idea of sizing here is a sample set of configurations. The dimensions below exclude the deflector footings as they are a component of the existing channel width.

Sample Configuration Sizing Without Ramp

1m Deep Channel Height Width Length
7m Containment Bay 1m 4m 14m
10m Containment Bay 1m 4m 17m
15m Containment Bay 1m 4m 22m
20m Containment Bay 2m 4m 27m

Sample Configuration Sizing With Ramp

1m Deep Channel Height Width Length
1.0m Deep Channel 1m 4m 23m
1.5m Deep Channel 1.5m 4m 26m
2.0m Deep Channel 2m 4m 29m
2.5m Deep Channel 2.5m 4m 32m


Note: These figures are indicative only and do not represent the largest or smallest sizes we can treat. If you need an estimate size for your plans please contact us and we will be able to provide this informaiton to you over the phone, if you can provide some or all of the site details.


The Deflector trap is generally not suited as a lidded solution, however this cannot be ruled out until the site details are known.

Pollutant Storage

The Deflector trap is a candidate for either on-line or off-line storage.

Trap Access

The Deflector trap is a candidate for either Left or Right hand storage. The Containment Bay size is determined by various factors such as the cleaning frequency, catchment size and makeup.

Depending on the site and cleaning requirements the Deflector trap can be accessed via a ramp at either end or internal step irons.


Although Deflector Traps are normally cast insitu, they can be constructed using a combination of methods, whichever suits the site conditions. Standard equipment and modular construction combine to make installation convenient with minimum interruption or alteration to existing conditions.

Deep excavation is not required with the Deflector Trap.


Cleaning of the Deflector Trap is dependant on the site requirements but any of the following can be used with this design of trap.

  • Eductor Vacuum
  • Backhoe/ Bobcat
  • Clam Shell
  • Manually Cleaned

Please Note: If a trap is to be cleaned manually, there are minimal Occupation Health and Safety issues even though the captured pollutants are dry. 

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