Attachment 4 - Engineering Report · MCU18/0015

DETENTION TANK DESIGN — RESIDENTIAL LOT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Rainfall wtensities (mm/hour) Tate Page
ARI (years) 1 2 70 8650 100
Sminntestorm =» «130,185 224281320
{Ommutestorm 100 127,-«S 173,280 1 year ARI RyGOgreph
30 minute storm 60.2 76.5 105 133, 182
COminutestorm = 40.6 «51.9724 «88.1106 zen ARES
120 minute storm 28 «4334 481 651 726 10 year ARIhydrograph
50 year ARthydrograph
Catchment information 100 year ARS hydrograph
ATCA pronevpaent = 200m ca
a a, = 200 m?_ | Mediumdensity bush. or good grass cover, of Hs] .
N02 puamecpeen pecatones z gm? | Medium sal pemeabity (=) |
et = [oooly) (neneCy= O07 )
a = [100 [*) (neneCy= 69 }
f peepee (etch = Jo6o[y) ¢henceCw= 082 ) “!
me = 10min — Maximum water depth in tank is 1927mm
T.O.C. puma = 6 min |
Detention Tank information |
Gravity = 9.8 mis* }
Alea os = 245m
Ca = 062 |
|
Tank Outlet information Ss Notes/Heip
Orifice Number 1 2 3 4 5 6
Orifice diameter (mm) 55
Orifice invert level (mm)
Peak combined outitow from catchment (m*/s)
ARI (Years) 1 2 10 50 100
Qrre Qposr Ore Qrost Qrre Qros Pre Oost Qrre QPosr
§ minute storm 0.00 2.61 0.00 327 0.00. 4.61 0.00 5.96 0.00 6.36
10 minute storm 3.07 3.16 4.14 3.99 6.64 5.66 10.29 137 11.83 Tat
36 minute storm 3.62 3.54 4.89 449 7.590 64T 11.00 8.19 12.64 8.78
60 minute storm 3.15 3.24 4.27 421 7.01 6.34 10.07 8.33 11.60 8.99
120 minute storm 2.36 2.64 3.22 3.48 5.46 5.49 748 711 8.71 778
Maximum tank (mm)
ARI (Years) 1 2 10 50 100
§ minute storm 187.4 279.7 §275 863.0 978.9
10 minute storm 261.6 401.3 780.7 4304.4 1484.8
30 minute storm 321.4 502.2 1043.3 | 1604.3 | 1840.5
60 minute storm 275.0 444.9 971.8 1658.9 | 1926.6
120 minute storm 191.0 312.5 735.4 4215.9 | 1449.8