1. Supply pipes and channels
Based on supply of 10-raceway modules, each with minimum capacity 16 t at 0.8 lpm/kg, with usage factor of 80%: Phase I 46.08 m3 /min, plus allowance for hatchery etc. 50.0 m3 /min
Phase II 85.12 m3 /min (usage 70%), plus allowances, 90.0 m3 /min
Main
distribution pipe; allow 5 m pressure
drop at 130 m total equivalent pipe length (TEL); h = 5/130 =
0.0385; h 0.56 = 0.161
Phase I, with 3 pipes: Q, l/sec = .278 per pipe
278=4.5 × 10-4 × d2.69 × h0.56
d2.69 = 278 × 104/0.278 × 0.161 = 62
1.11 801
d = 789
Phase II use 6 pipes
Normal operations will require fewer pipes; at least one can be left free for cleaning.
Sectional supply channels
(a) Main
distributer channel; designed for Phase II flow, 90 m /min; say drop of 0.1 m/30 m length; S =
0.0033. At channel width 1 m, depth 0.8 m, CSA 0.8 m , WP = 2.6 m, R = CSA/WP = 0.308, required 
= Q/CSA = 1.875 m/sec.
Actual = 1/0.025 × R 2/3 × 5 1/2
= 0.456 × 0.057/0.03 = 1.04 m/sec
At width 1.2 m, depth 0.8 m, CSA = 0.96 m2, WP
= 2.8 m, R = 0.34
Required = 1.56 m/sec. With drop 0.15/30 m; S = 0.005; S 1/2 = 0.0707 = 1/0.025 × 0.487 × 0.0707 = 1.38 m/sec
It would thus be possible to deepen this slightly to carry peak flow.
(b) Distributer channels for fingerling/Phase II raceways. This will be required to carry ~ 60 m3 /min maximum. A size of 0.8 m × 0.8 m will be adequate
(c) Distributer channels. Phase I, phase II, ongrowing raceways. A size of 0.7 m × 0.8 m will be adequate for a design flow of 50 m /min.
2. Drainage
Main collection channel
Base on a design flow of 2.5 × individual main raceway channels, which are in turn based on inflow rate, plus emptying of three raceways in 15 minutes.
Raceway drains; 50 m /min + 28.8 m /min → 1.33 m3 /sec.
Thus main channel → 3.325 m3 /sec
At W = 3 m, d = 0.8 m, CSA = 2.4 m2 , WP = 4.6 m, R = 0.52
with S = 0–4 m/160 m → 0,0025 Required = 1.39 m/sec
Actual v .= 1/0.03 × 0.52273= 
= 1.08 m/sec
This with channel at say 1 m depth, flow can be carried.
Raceway channels
Flow = 1.33 m3 /sec, with W = 1.5 m, d = 0.8 m,
CSA = 1.20 m2
WP = 3.1.m,. R = 0.39; S = 0.0025; required = 1.108
Actual = 1/0,025 × 0.534 × 0.05 =1.068
Thus if depth is 0.9 m,
wastes could be accommodated
Finger ling raceways
A slightly bigger channel will be required to take the combined flow of the fingerling raceways plus the Phase I raceways down to the main collection channel.
Note: These sizes are indicative only; it will be necessary to re-evaluate sizes once complete site and project data are confirmed, relative costs defined, and design strategy comfirmed. Thus considerable oversizing may be appropriate if it is considered that additional flows will be used later e.g. by developing the other quarry area or by increasing stock loads in the longer term.
