Stormwater Management Plan MCU17/0014

BORNHORST + WARD | DOONELLA STREET UNITS



         3.         DEVELOPMENT PROPOSAL

         3.1        PROPOSED DEVELOPMENT

                    The proposal is a development which will comprise of 10 residential units and 3 commercial tenancies with off
                    street parking provided within a basement car park. The residential units will be situated to the north of the
                    site, while the commercial buildings are proposed in the south. As per a previous development approval for
                    the site (MCU15/0053), NSC has requested a 3m public thoroughfare easement be provided along the
                    northern boundary of lot 32. Refer to the Archicology Architectural Plans within Appendix A for further
                    information

         3.2        PROPOSED STORMWATER DRAINAGE

                    It is proposed to maintain Doonella Street as the lawful point of discharge for the site as per existing
                    conditions. Internal stormwater drainage infrastructure will convey minor storm flows (AEP greater than 10%)
                    to proposed treatment devices and an underground detention tank. The minor storm flows will then discharge
                    into the existing stormwater gully pit within Doonella Street. Major flows (AEP less than 10%) will flow towards
                    Doonella Street as overland flow as per existing conditions. Refer to the Stormwater Layout Plan within
                    Appendix B for further information. There are no external catchments affecting the site. It is noted that runoff
                    from the Sidoni Lane Capark is currently directed west towards an inlet on Sidoni Street away from the site.

         4.        STORMWATER QUANTITY

                    An extract from Part 14 - ASSESSMENT CRITERIA FOR DEVELOPMENT FOR A STATED PURPOSE OR OF A STATED
                    TYPE of the Noosa Plan states:

                    The overall outcomes sought by the Water Sensitive Design Code are to ensure that—
                            a) development is designed, constructed and operated in a manner that contributes to, and does
                            not impede, long term attainment of relevant Environmental Values and Water Quality
                            Objectives as specified in the Environmental Protection Policy 2009;
                            b) development avoids adverse impacts on downstream ecosystems, properties and
                            infrastructure due to changes to stormwater flow, water quality or ecosystem health;
                            c) stormwater conveyance channels use natural channel design principles to convey external
                            catchment stormwater through development and support landscape, passive recreation and
                            ecological values;
                            d) urban development captures and utilises run-off from appropriate areas for use on site; and
                            e) water reuse facilities have no adverse impact on the quality of the town mains water.

                    All stormwater discharge will comply with Noosa Shire Council’s The Noosa Plan and Stormwater Management
                    Code with quantity calculations completed in accordance with the requirements and methods outlined in the
                    Queensland Urban Drainage Manual (QUDM).

         4.1       PEAK FLOW CALCULATIONS

                    Modelling of stormwater runoff quantity has been considered for the existing site conditions and operational
                    phase of the development. The Rational Method as outlined in QUDM was used to determine the peak flow
                    rate corresponding to the minor and major storm events for this development.



 Bornhorst + Ward Pty Ltd
 Level 4, 67 Astor Terrace, Spring Hill, Qld 4000                                                                      Page 3
 Ph. (07) 3013 4699 / [email protected]
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