Stormwater Treatment & Water Quality Management Plan_April2014

                                                                             Callaghan & Toth


1.       SUMMARY
The key points of this investigation are as follows:
   1. Runoff from new roadways, footpaths and allotments is to be cleaned of nutrients and
      gross pollutants via a stormwater treatment system prior to being released to existing
      waterways.
   2. The stormwater treatment system includes:
                   a. One small Bioretention Basin (already completed for Stage 1)
                   b. Two medium Bioretention Basins located in park,
                   c. Three small Roadside Bio Basins,
                   d. Two Bioretention swales,
                   e. Three Raingardens for Lots 26, 27 & 28, and
                   f. One Grassed Buffer.
   3. The increase in pollutant loads due to the increase in impervious areas is to be
      attenuated.
   4. Stormwater Detention is to achieve no increase in runoff concentration by the following
      measures:
                   a. Riparian vegetation planting to attenuate flood flows:
                   b. Pedestrian bridge over the eastern tributary (off Lake MacDonald Drive)
                       to attenuate flows;
                   c. Detention storage in Bioretention Basin 2 and 3;
                   d. Reshaping of the western tributary (off Blue Wren Place) to provide
                       greater flood storage.




55 Lake MacDonald Drive – Stage 1 to 5                                                 pg. 5