Att 3_CMP - Final

             A rumble pad should be constructed at least 2 metres wide and consist of 40 mm
             crushed rock places 150 mm to 200 mm thick over geotextile filter cloth for a minimum
             distance of 10 metres. Where necessary 20 mm aggregate should be placed to allow
             pedestrian traffic safe access. Pre-fabricated rumble grids should be located over
             geotextile cloth.

     5.2     Roadside gully inlet sediment barriers
             For safety reasons and sediment efficiency, sediment barriers generally should not be
             located outside site boundaries without Council approval. This especially applies to
             sediment barriers placed on roadways.

             Sediment barriers placed in front of roadside stormwater inlets are rarely as effective as
             onsite controlled and at best result in sediment being washed down the road and into
             the nearest open gully inlet.

             They should be only used as last resort and if installed, they should not fully block the
             inlet structure (Figure 4 & Figure 5). Figure 6 shows an alternative arrangement.




                                       Figure 4: On-Grade Gully Inlet




                                          Figure 5: Sag Gully Inlet




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