Question

Your company has been commissioned to design the water supply pipe network of 25 villa-style home units arranged in five buildings each containing five units on a steeply sloping side. The minimum available pressure at the main tapping is 35 m head, and the furthest fixture outlet is 7.5 m above the main (consider each row of buildings are 1.5 m higher than previous row adjacent to the street). The length of internal piping to the remote outlet in unit 25 is 13 m. THe suggests to include the following items in

• Pipe sizing of 25 villastyle homes with appropriate calculations and drawings
• Sizing of internal pipework of all the units
• Use appropriate tables to show calculation steps
• Sizing of internal pipework of units
• • Location of main
  • Unit numbers
  • Pipe lengths
  • Water flow quantity
• Pipe diameters

Answer 1

Hazen william Nomogram for pipe flow

Pipe	Population served	Max discharge (lit/s)	Assumed diameter	Head loss	Net head m		Velocity
	Previous	Local	Total P	2.7*200*P/(24*60*60)	mm	Rate per 1000m	Length	Actual loss = rate*length	35 - ground ht -head loss		m/s
JK	100	25	125	0.781	100	50	225	11.25	16.25	35-7.5-11.25	1.6
HI	75	25	100	0.625	80	80	100	8	21	35-6-8	1.9
FG	50	25	75	0.468	70	125	100	12.5	18	35-4.5-12.5	2.1
DE	25	25	50	0.3125	60	175	100	17.5	14.5	35-3-17.5	2.3
BC	0	25	25	0.156	60	175	100	17.5	16	35-1.5-17.5	2.3

Use 25 mm dia pipe for internal connections.