WATETANK

Catchment & Water tank Construction

-Because the large rainfall that occurs throughout the area

-Installing a Water tank is a definite solution

Catchment calculation

determine possible total roof catchment

Proposed possible roof total area
=432.00

432.00 (total area) x 1.29 (Slope factor)
=557.28

=557.28 (total roof catchment area)



Downpipe size and location

From table 3.2, in AS3500.3.2 and HB114

The minimum size downpipes compatible with Spouting of 6125mm2 cross sectional area (Installed at a 1:500 gradient) are 90mm diameter round or 100 x 50 rectangular. I selected the 100 x 50 rectangular downpipe.

From figure 3.6 AS3500.3.2 and HB114

The Maximum catchment per downpipe is 47 m2

Determine existing water usage patterns, and advise on additional water saving measures if required.

Firstly, work out the average rainfall (mm) per month

653.2 (Total mm/ per year) / 12 (months)

=54.43 (mm per month)

Then work out the amount Litres of water used on average each month

Rainfall (mm) x Catchment Area (m²)

54.43(mm) x 172.457(m²)

=9386.83L (per month)

To work how many litres we used on each section

The average Victorian urban Household consumes 210,000L per year

210,000 (litres per year) / 12 (months)

=17500 L (per month)

Garden Use = 50%= 17500/ 50%= 8750 L (per month)

Bathroom = 10%= 17500/ 10%=1750 L (per month)

Hot Water = 15% = 17500/ 15%=2625 L (per month

Toilet = 10% = 17500/ 10%=1750 L (per month)

Laundry = 10% = 17500/ 10%=1750 L (per month)

Kitchen = 5% = 17500/ 5%= 875 L (per month)

260 L Everyday

Example: 4524 (Balance in Tank) + 3687 (Yield From Fortnightly)

8211 – 4030 (Usage L)

4181 Balance in Tank