5255NSCResponse

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Callaghan & Toth |

1. INTRODUCTION

This Management Plan has been prepared to analyse the existing stormwater drainage issues
in Key Court and then to determine if an overload flow path with associated easement can be
created over the existing stormwater outlet which crosses No.19 Key Court.

This investigation and design was requested as part of Noosa Council's Information Request
dated 4 November 2020 Item 2.

2. FLOODING MANAGEMENT PLAN
2.1 Proposed On-Site Stormwater Easement

An existing 0.6m wide x 0.3m high box culvert extends from Key Court to the canal
approximately 1.1m inside 19 Key Court adjacent the eastern boundary.

Council's Information request dated 4° November 2020 Item 2 requires that an easement
location be to be identified for the 1% AEP flows from the relevant catchment.

We have indicted the location of a 3m wide easement on Plan 2103-03 which also shows the
proposed house footprint in relation to the easement.

This easement is designed to take the difference in flows between the 1% AEP pipe flow and
the total 1% AEP for a local storm burst.

2.2 Existing Conditions

The house has been removed from the Lot 2 No. 19 site and a survey has been carried out.

The sag point is the road is in the driveway to No.17 Key Court 6m east of the proposed
easement location.

The road boundary is currently fenced with a continuous block wall across the proposed
easement.

The proposed easement slopes towards the canal. The natural surface has been disturbed by
demolition.

The existing pipe under the proposed easement is 1.65 m to invert at front boundary and 0.67m
to invert at canal wall.

2.2.1 Pipe Network

The existing pipe network starts with sag gullies at the intersection of Key Court and Noosa
Parade and extends through No.19 Key Court to the canal. The network picks up all surface
water from Key Court and adjacent residencies.

 

2103 19 Key Ct SWMP February 2021