Attachment 4 - Stormwater Managment Plan

SQIDEP Evaluation                                                   SPEL Basin, Sippy Downs


       noted that hard stand catchments will behave similarly. Cleaner, roof catchments
       may not achieve the same pollutant reduction targets.

   2. The results are for a hydraulic loading rate up to 250m/year. Should the hydraulic
      load rate exceed this, the results and life expectancy of the media would be expected
      to decline in line with excessive loading on the device.

   3. The results are reliant on the maintenance of the device being consistent with the
      manufacturers guidelines and those that are contained in the report. Most importantly
      the cleaning of the Storm Sack and filter cartridge at regular intervals.

   4. The life expectancy of the device and the media is unknown. In discussions with the
      manufacturer the testing is consistent to at least the 6 year mark. It is suggested that
      an estimated lifespan of both media and the whole device be written into any
      technical guidelines as the filter material will deteriorate over time.

   5. The acceptance of these results is reliant on the installation being similar to that
      shown in this analysis. Alternative installations may result in different outcomes.

Recommendation for Associated Technical Guidelines

The results of this analysis can be seen to be reliant on a number of factors, a number of
which could be tied strongly to a set of technical installation and maintenance guidelines. As
such it is strongly recommended that the SQIDEP results be tied to a product guideline to
ensure future consistency.




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