Topic I.8. Water Supply Networks: Kinds, Structures and Design

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 Networksa. Branched b. Looped (Gridiron)

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

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

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 300 - 600 m each to the other • The trunks along the main water distribution direction have to be connected with intermediate trunks at distance of about 400 - 800 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. Cast iron socket a - pipe longitudinal section б - socket joint detail 1 - pipe cylindrical end 3 - resin rope 2 - pipe muff end 4 - plumb or asbestos-cement stuffing Pipes Joints

10. Cast iron pipes sockets a - socket joint б - screw-socket joint 1 - pipe cylindrical end 3 - rubber gasket 2 - pipe muff end 4 - screw ring Pipes Joints

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

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