20517 App J.pdf [As Published] · 132007.1259

Concept Stormwater Management Plan
Essence of Peregian

 

RL 2.5 m AHD at the western boundary with Noosa National Park. The site’s average grade is approximately 3.5%,
however is steeper on its eastern side and flatter on its western side.

A discharge point for stormwater drainage is located at the southern boundary. Some existing buildings and roads
at the south eastern comer of the site are drained by a pit and pipe system that discharges via pipe outlet to a
vegetated gully near the southern boundary. This gully then crosses the southern boundary and enters Noosa
National Park. Runoff from other parts of the site drains to the western boundary as sheet flow. From site
inspection there appears to be no evidence of erosion from this surface drainage. This is due to low grades and a
well grassed area immediately prior to where runoff flows across the western boundary.

Documentation from Noosa Council's Geographic Information System (GIS) and detailed site survey shows piped
stormwater drainage from the Peregian Beach Hotel site drains through Lots 9 and 10 on RP9315 and Lot 76 on
Crown Land Plan MCH 2969. Property drainage lines from Lots 8, 9 and 10 possibly connect to this pipeline. This
pipeline appears to connect to the Council drainage system under the road south of Lot 8. Council's GIS system
map shows that the Council piped stormwater system drains part of David Low Way to the east of the site.
Following the junction of these two pipelines under the road south of Lot 8 the common pipeline discharges to Noosa
National Park to the south.

3.0 FLOODING

Brown Consulting (QLD) Pty Ltd was not engaged to undertake a flood study for this development proposal.
However, the following comment is presented on this matter.

Brown Consulting made a Property Search Request on 16 April 2006 for the subject site specifically for minimum

floor heights or flood level information as applicable to the property. Noosa Council’s response (Search 07 1329) .

stated the subject property is not within an area subject to minimum floor heights as established under Council's
amended Planning Scheme and has no nominated or historical flood levels held in Council’s records.

Based on “Flooding in the Noosa River Catchment” Noosa Council Strategic Planning as per Aug 1995, (updated
February 2000 and June 2001) the 100 year ARI flood level for nearby Lake Weyba is RL 2.05m AHD. Based on

the flat topography across the national park, between the site and the lake, it is believed that the flood will be similar. .

The freeboard applied to the Lake Weyba area is 800mm. Therefore any fluctuation in the flood level is unlikely to
have adverse impact on habitable floor levels. Therefore the minimum floor level at the site is likely to be
RL 2.85m AHD.

A search of Noosa Council’s Planning and Development publications was conducted. It was found that the site falls
within the Eastern Beaches Locality Plan. The Natural Hazard: Landslide and Flooding Overlay to this locality (Map
OM4.3) shows that the site does not fall within the flood hazard area as nominated by Council.

ey |

 

B07047-01A.doc Page 3