Ral 17 0511 Rfi

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    3. Provide preliminary engineering designs of the access driveway to the house sites on
       Lots 2 & 3 and the associated storm water system. The designs must be based on
       the flood modeling of the site and be in accordance with QUDM providing for safe
       access for pedestrians and vehicles.

    3. Please refer to plans 1707-01E, 1707-03A, 1707-04A, 1707-05A showing layout
       and long/cross sections for lots 2 and 3. The designs are based on site flood
       modeling, refer to BSM report dated 21-2-18 section 3.6 page 12 showing safe
       access and QUDM compliance. The velocity of flow and depth adjacent to
       driveways is very low.

Access and Frontage Works

    4. Provide additional detail (comment and plans) in regard to:
          a. The suitability of the access to Lots 2 & 3 including sightlines and services.
          b. The proposed access points for Lots 1 & 4.
          c. The extent of frontage works (kerb and channel, footpath, road widening)
              proposed by the applicant.

    4. Please refer to the following:
          a. The access for lots 2 & 3 was checked on site for adequate sight
             visibility, refer to plan 1707-1E and notes below.

                In the southbound approach to lot 2/3 driveway along Church Street,
                cars stop at the intersection to cross Red street or turn into Church
                street resulting in a low speed entry. We estimate southbound approach
                speed to be 45km/h based on this and the speed environment of the
                street. Based on AS2890.1 the required sight distance is 35m (domestic
                minimum) to 40m desirable. With removal 2-3 of small trees that are
                growing out on and angle towards road (see Figure 1 below
                approximately 75mm diameter) there is 70m southbound visibility to
                driveway which is above requirements. These trees will require clearing
                for future footpath, and path will ensure sight visibility is maintained in
                future.

                The northbound approach has excellent visibility with 200m sight
                distance.

                Council policy prefers that driveways are located away from existing
                services when possible. We have moved lot 2/3 driveway to avoid an
                existing fire hydrant in the road reserve. Driveway finished level is at or
                slightly above existing so there is no impact on cover to existing
                services.




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                  Figure 1: Proposed small tree removal for sight visibilty


            b. Lot 1 frontage to Church Street is the proposed access point. As noted
               above lot 2/3 access has sufficient southbound visibility and excellent
               northbound visibility. Therefore Lot 1 can have a driveway at any point
               along frontage, and location should be the future owners decision
               based on house location.

                Lot 4 is considered a balance area at this point, as it is proposed to
                stage the subdivision reconfiguration and Operational Works as
                follows:

                        Stage 1: Lot 1 including frontage works to end of lot 2/3
                         boundary (refer to 1707-2B).
                        Stage 2: Lot 2/3 (refer to 1707-2B).
                        Stage 3: Lot 4 Balance Area (refer to 1707-2B).

                Given that Lot 4 balance area is likely to be re-subdivided in future we
                have indicated a possible driveway location to prove that access to area
                is possible in relation to flooding. As driveway location is likely to
                change as a result of future subdivision it is not intended to construct
                this culvert or driveway until future plans for this balance area are
                submitted to Council and approved. There is a small pipe and crossing
                just downstream of culvert shown on flood report in gully at present
                that enables access for mowing.

                Lot 4 access point as shown on plan 1707-01E has in excess of 60m to
                southbound approach (can see to Red street intersection). So with
                45km/h approach speed the sight visibility is acceptable as it is greater
                than 35m required by AS2890.1. There is 70m visibility to northbound
                approach from Red Street which is also acceptable.




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            c. The extent of frontage works proposed is as follows;

                        Stage 1: Lot 1 including frontage works to end of lot 2/3
                         boundary (refer to 1707-1E).
                        Stage 2: Lot 2/3 (refer to 1707-1E).
                        Stage 3: Lot 4 frontage.

                The proposed 5.5m road width between lot 2/3 entry and just north of
                existing twin 1200mm diameter culverts in Church Street is considered
                adequate because;

                        It will save existing trees and gully at crossing. Widening culverts
                         and road at this point would require extensive clearing and
                         reduce amenity/appearance of existing area.
                        Limiting parking at this location is preferred as Church street
                         flooding occurs often according to BSM (overtopped ARI 10
                         existing/developed normal rainfall, overtopped ARI 5
                         existing/developed climate change rainfall) and Q100 depth is
                         approximately 0.28m to 0.33m (climate change). Also due to
                         flooding there will not be dwellings in that location and won’t
                         need parking.
                        Existing water main passes close to culverts at present and
                         widening may require expensive alterations.
                        Existing road width is same as proposed, and with trees this
                         creates a low speed environment which is desirable to maintain
                         for safety.



We hope that this information will allow for approval in the near future, please call with any
queries.




Yours faithfully,




A Haynes BE Civil (Hons) MIE Aust RPEQ CPEng
CC Mark Jones




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