Response to information request REC13/0095

    "1



Callaghan & Toth Consulting Engineers Pty Ltd
ABN No: 45140292324


8/41 Sunshine Beach Road NoosaJunction
P.O Box 2305 Noosa Heads 4567
                                                                                                               Callaghan & Toth
www.callaghwlandtoth.com.au
Ph: 07 5474 9081 Fax: 07 54749041
                                                                                            Civil, Environmental & Hydraulic Engineers

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          10th September 2013                                                                                                         File No: 1225


         Sunshine Coast Regional Council
         C/- Max Watterson and Associates



         Dear Sir/Madam,


         RE:"         REC13/0095. One lot into 4 lots at 55 Lake Macdonald Drive Draft Conditions



         We are writing to respond to information request dated 24th July



               1. Information Required.


         Attached are our OPW design plans 1225-17 to 30, which detail:
             a. Longitudinal sections of driveways on plan 21

               b.    Plans 19, 20 and 24 clearly show the extent of any necessary batters, banks, drainage
                     structures and scour protection.
               c.    Plans 20 and 24 clearly show the extent of any earthworks necessary to ensure that the
                     overland flow is free draining.
               d.    Plan 24 shows a typical cross-section at the culvert. All culverts have the same minimum
                     cover.

               e.    Plan 18 shows the proposed trees for removal as per the Arborist report, which is
                     attached.



               2.    Information Required.


         Our Reconfiguration plans show the driveway edge to the lots to be 1.5 meters off the adjacent
         boundaries. During detail design, it was found that the driveways needed a 0.5 shoulder each
         side and 1 in 3 batters as well as headwalls and outlet scour protection. These details resulted in
         the driveway edge being increased to 2.5m from the boundary to give adequate separation.


         We do not agree with the concept of combining driveways to lots five and 6as in the past there
         arises issues as to where to put the fence and gates and who is responsible for fixing the shared
         driveway and pipe. Therefore, we submit our amended separated driveways as shown on plan
         19,20,21 and 24 for consideration.


               3. Information Required.


         We enclose a response from 8risbane Stormwater Management (8SM)to address this query
         and Plan 1225-198,which accurately represents the regional flood extent on site including lot 5
         based on Council Flood model levels and survey contours over the site.


         Note that we also compared this to the Council flood extents on mymaps and found Council
         Q100 mapping is completely outside Lot 5.


         The adopted flood study for this area uses an average n value of 0.064 (n = 0.06 for bed, n=
         0.03-0.05 for cleared flood plain). A small portion ofthe gully parallel to Wilgee Court fronting lots
         5-7 has some existing Q100 inundation according to Plan 1225-198.




         X:\Jobs\CT Projects in progress\1225 30 lots lake MacDonald DrivelCorrespondencelSlage 2 CorrespondencelREC Info requesl response.doc