RFI - P0478-26-001_45_Maple_Street_Cooroy_SWMP

Executive Summary
RECOR Consulting Engineers have been engaged by Myall Rise Pty Ltd to prepare a Stormwater Management Plan
(SWMP) to support a Development Application for a proposed Material Change of Use from a single residential
dwelling and shed, and a vacant lot, to multiple dwellings at 45 Maple Street and 9 Myall Street, Cooroy.

This SWMP outlines the proposed stormwater management strategy and demonstrates compliance with the Noosa
Shire Council (NSC) Planning Scheme Policy – Stormwater Management, the Queensland Urban Drainage Manual
(QUDM), and relevant Water by Design guidance. The assessment confirms that the development can be
constructed and operated in accordance with applicable stormwater quantity and quality objectives.


1.1        Lawful Point of Discharge

Stormwater runoff will be conveyed to the on-site detention (OSD) tank and discharged via a lawful point of
discharge into Council’s existing stormwater network within Myall Street, to the east of the site. The system
provides a controlled release and integrates with existing infrastructure in accordance with QUDM requirements.


1.2        Stormwater Quantity

A hydrological assessment was undertaken using both the Rational Method and DRAINS modelling to establish
pre-development conditions and assess post-development impacts.

The proposed development increases impervious area and runoff potential. To mitigate these impacts, a proposed
OSD tank has been incorporated into the design. The detention system captures stormwater runoff from the
proposed development and attenuates peak flows prior to discharge.

Modelling confirms that post-development peak discharges are equal to or less than pre-development flows for
all assessed storm events up to and including the 1% AEP event. Existing overland flow paths and site grading are
maintained, ensuring no adverse impacts to adjoining properties.


1.3        Stormwater Quality

A stormwater quality assessment has been undertaken in accordance with the Urban Stormwater Quality Planning
Guidelines (2010), the Water by Design framework, and the State Planning Policy. The assessment demonstrates
compliance with applicable pollutant load reduction targets through the incorporation of an engineered treatment
solution.

A proprietary cartridge-based filtration system will be integrated within the OSD tank to provide treatment through
filtration and pollutant capture. The system is expected to achieve compliant reductions in sediments, nutrients,
and gross pollutants, ensuring no adverse impact on downstream receiving environments


1.4        Erosion and Sediment Control

During the construction phase, ESC measures must be implemented in accordance with the applicable
requirements.




 45 MAPLE STREET, COOROY
                                        24 June 2026                                               P a g e |3
 Stormwater Management Plan
 Client Reference: P0478-26-001
 Prepared for Myall Rise PTY LTD