Approved Documents

2D

of roads and swales. Details of this model can be found in Section 4.0.

To detain the Qzy flow from the roofwater runoff it has been proposed to construct a pipe
network which contains 450mm and 525mm Nominal |.D FRC Slotted Pipes. Refer to
Figure 4 to view the proposed locations of the 450mm and 525mm slotted pipes.

The Infiltration System has been designed to contain and infiltrate the Qa roofwater
runoff. Due to the fact that the infiltration system is only containing the Qzo flows from the
roof, the XP-SWMM model has allowed for the remaining roof flow (Q100 — Qzo) to be
taken by either the stormwater pipe system or via overland flow. The Infiltration system
will also act as a water quality system with all runoff collected in the infiltration system
being treated through the sand layer before being discharged downstream in the
melaleuca swamp.

The following Table shows the required length of 450mm and 525mm Nominal |.D FRC
Slotted Pipes required to detain the volume of roofwater runoff for the 20 year ARI storm
event. Details of Infiltration sub-catchments can be found on Figure 4.

Table 2 _ Pipe Lengths required for storage and infiltration.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sub - 450 mm or | Number of | Length of | Available Required
Catchment| 525mm pipes Pipe Volume of Volume of
FRC Pipe (m) Storage (m’) Storage (m’)

1 450 3 24 12 12

2 450 3 24 12 12

3 450 3 24 12 12

4 450 3 12 6 6

5 525 2 16 7 6

6 525 1 92 21 21

7 525 2 16 7 6

8 450 2 20 7 6

9 525 1 40 9 9

10 450 2 36 12 12

11 525 1 60 13 12

12 525 1 44 10 9

13 450 2 36 12 12

14 §25 2 40 18 18

415 450 2 108 35 33

16 525 2 76 33 33

17 450 2 60 20 18

18 525 2 16 7 6

19 450 2 16 9 9

20 525 3 32 21 21

21 525 2 48 21 21

22 525 2 16 € 6

23 525 2 16 7 6

Total Volume (m’) 318 306
Is there Satisfactory Storage to Contain the Qz2) Roofwater Yes
runoff?

Noosa Domain Retirement Village, Noosaville 6 Site Based Stormwater Management Plan
M1717 Revision B 16 August, 2006