ADAMS+SPARKES Response to Information Request (Gympie Tce) 160401

17-0022/T0070




                 TECHNICAL MEMORANDUM
 TO:                          John Titmus

 COMPANY: JTC Consulting Engineers

 FROM:                        Steven Chamberlain (RPEQ 15,545)

 SUBJECT:                     111-113 Gympie Terrace, Noosaville – Hydraulic Modelling

 OUR REF:                     T0070

 DATE:                        1 March 2017



1               INTRODUCTION
Preliminary hydraulic modelling has been undertaken of the existing and proposed drainage infrastructure to the
south of the proposed development. This assessment has been undertaken to determine the extent of ponding
associated with the inlet pits in the Sea Scouts site. The modelling described herein has been undertaken following
discussions with Noosa Shire Council (NSC) officers and is not intended to be a detailed flood assessment.


2               HYDRAULIC MODELLING METHODOLOGY
Civil works associated with the proposed development have been prepared by JTC Consulting Engineers and
HAYDN Civil Designs. The modelling was undertaken based on the data contained in:

       •     JTC Consulting Engineers Job Number 216131, Drawing Numbers OP1 to OP4, and
       •     HAYDN Civil Designs Job Number 216131, Drawing Numbers SK01 to SK03.

The hydrologic and hydraulic modelling software XP-SWMM was utilised to model flows through the existing and
proposed culverts and assess the depth of ponding on the Sea Scouts site in the post-development scenario.

2.1.               FLOW RATES

The peak flow rates for the 100 year Average Recurrence Interval (ARI) event, and time of concentration detailed
in Drawing Number SK03 were utilised to create a simplified triangular hydrograph. Refer to Figure 1 for the
catchment extents, peak flow rate and time of concentration (time to peak) applied.




Environment. Engineering. Education                                                                            Page 1