Development Application Part 2 of 2 - Geotech Report and Plans - OPW13/0816

                                                               -7-


                                                                                                    Job No. 213-15522


        6.1.2       Revetment Stabilisation                (~P       ILO r-I   2...)
 It is essential relevant authorities be consulted regarding the stabilisation measures recom-
 mended in this report as the recommended remedial works extend into the Weyba Creek.


 We also advise that stabilising the creek frontage of No. 25 Dolphin Crescent
                                                                            may adversely
impact on adjacent waterfront properties due to possible/probable changing water flows
around the rock protection and this must be considered prior to remedial works. It was also
bouqht to our attention that immediate adjacent properties have also experienced the
adverse effects of scouring in Weyba Creek, however, the extent of damage or remedial
works undertaken was not assessed as part of this investigation program.


 It is recommended the Weyba Creek bed revetment frontage at no. 25 Dolphin Crescent be
stabilised by the creation of a working platform of sand (where piles are required) and revet-
ment rock at a temporary 2H:1V profile). A surficial capping of revetment rock, on a
                                                                                     geofab-
ric should be placed. The revetment rock, typically well graded sound rock of nominally
+75mm, -300mm
                  grading, at least 500mm minimum thickness, placed over a geofabric
layer, ie. Elcomax 600R, or similar, and extending from at least Highest Astronomical Tide
(HAT)level on the replacement revetment wall, or to platform level if a replacement wall is
not proposed, and extended into the Weyba Creek to the invert level of the adjacent scoured
creek bed. Figures indicate schematic recommended rectification profiles.


                                                          Option 2


     /                                                                                   NOT TO SCALE
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                             :                                 1!               Existing Scoured Profile
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        Figure 2




                                                               ’#,SOIL SURVEYS ENGINEERING PTY LIMITED
1-15522, 2013-09-20, LR VER 0