1. Topic I.8. Water Supply Networks: Kinds, Structures and Design
Kinds of Water Supply Networks
I. According to the hydraulic connections
Branched
Looped (Gridiron)
II. According to the static head arrangement
Non-stratified (Non-zone)
Stratified (Zone)

2. Kinds of Water Supply Networks a. Branched b. Looped (Gridiron)

3. Kinds of Water Supply Networks
Zone Network with Steep Terrain
a - Gravity System б - Pumping System
1 - minimal static head 2 - maximal static head (H < 60 m)

4. Zonal (Stratified) Network
a - Sequencing pumping zones feeding
б - Combined gravity and pumping zones feeding
b - Two pumping groups
г - Single pumping group

5. Water Supply Networks Structures
Main Elements
Mains (Trunks)
Branches
Fittings
Valves

6. Mains (Trunks) Design Basic Requirements
Main direction of the trunks must comply to the main water distribution direction. For this equally loaded parallel trunks have to be established at distance of about m each to the other
The trunks along the main water distribution direction have to be connected with intermediate trunks at distance of about m each to the other
So designed trunks and the rings formed by them have to cover uniformly the settlement, passing through the most dense populated regions and by the big local consumers
The trunks permanent ways have to be located at the higher parts of the settlements, which will insure uniform spatial distribution of the water dynamic head
The trunks permanent ways have to consider the soil properties, as well as the underground communications

7. Branches Design Basic requirements
The distribution branches are laid out along any one of the streets in the settlement in the way to deliver water with the shortest permanent way from the nearest trunk to the consumers
At the streets broader than 16 m two parallel branches could be install. If the branch diameter exceeds 300 mm, it is constructed as a transit one and a parallel branch with smaller diameter distributes water towards the attached consumers
Minimal slope of the branches is normally 0,1 %, or no less than 0,05 % at flat terrain
Stop valves have to be envisaged at the points of the trunks branching and at the beginning and the end of every branch in the way to allow distribution network rings to be isolated in a case of emergency
Fire valves have to be envisaged, uniformly distributed on the water supply network and at no more than 100 (150) m distance each to the other

8. Pipes, Fittings and Valves
Distribution Networks Pipes Materials
Cast iron
Steel
Asbestos cement
Plastics - PE, PP, PVC
Pipes joints
Socket (muff, muffle)
Flange
Clutch (union)
Weld
Gluing

9. Pipes Joints Cast iron socket
a - pipe longitudinal section б - socket joint detail
1 - pipe cylindrical end resin rope
2 - pipe muff end plumb or asbestos-cement stuffing

10. Cast iron pipes sockets
Pipes Joints
Cast iron pipes sockets
a - socket joint б - screw-socket joint
1 - pipe cylindrical end rubber gasket
2 - pipe muff end screw ring

11. Pipes Joints Asbestos-cement pipes joints
a - “Simplex” type б - “Gibot” type b - Flange type
1 - rubber gasket
2 - pipe

12. Fittings Kinds of Fittings T-fittings (with or without flanges)
Cross-fittings (with or without flanges)
Offsets (with or without flanges), 30o, 45o , 60o and 90o
Knees (Elbows) - with or without flanges, 45o and 90o
Reducing fittings (Confussors/Difussors) - with or without flanges
Duff flanges

13. Valves Kinds of Valves Stop (Gate) valves Fire hydrants
Pressure reducing valves
Air valves
Blow off

14. Valves