IMPROVED AND INOVATIVE RURAL WATER SUPPLY DESIGN CONCEPTS

1. IMPROVED AND INOVATIVE RURAL WATER SUPPLY DESIGN CONCEPTS DULEEPGO@GMAIL.COM

2. The purpose of water treatment is to provide a continuous supply of safe, palatable/potable drinking water • Free of chemical contaminants The Need for Water Treatment • Free of Disease-causing (biological) contaminants • Free of unpleasant characteristics • Colour • Turbidity • Taste and odour • Free of plants like algae RRPN Ratnayake

3. All the above physical and chemical characteristics are mainly due to suspended matter or dissolved chemical constituents in the water In simple terms Water treatment is the removal ofUnwanted suspended /dissolved matter (solids, liquids or gases) from water SLS 614 USEPA drinking Water Regulations RRPN Ratnayake

4. Particle Size & Settling Rates RRPN Ratnayake

5. TRAY AERATOR When PH above 7.5 4Fe2++ O2+10H2O 4Fe(OH)3+8H+ 2Mn2++ O2+2H2O 2MnO2+4H+ (Better if PH >9.0 for Mn oxidation) Trays filled with coke, crushed stone, lime stone or plastic media up to a depth of 300-450mm.

6. RRPN Ratnayake

7. INDUSTRIAL POLLUTANTS

8. TREATMENT PROCESS SELECTION Turbidity< average of 5 NTU, Algae (Chlorophil <.05µ)g/l,Colour, Taste, Odour, Iron<.3mg/l, Manganese<0.05mg/l, Algal toxins (to be tested) Slow sand filtration Turbidity< average of 20 NTU and maximum up to 50 NTU, Algae (Chlorophil <.05µ)g/l,Colour, Taste, Odour, Iron<.3mg/l, Manganese<0.05mg/l, Algal toxins Slow sand filtration Aeration Turbidity< average of 20 NTU and maximum up to 200 NTU, Algae (Chlorophil <.05µ)g/l,Colour, Taste, Odour, Iron<.2mg/l, Manganese<2mg/l, Algal toxins, fluoride<0.8mg/l Roughing filtration Slow sand filtration Aeration Turbidity< average of 60 NTU and maximum up to 500 NTU, Algae (Chlorophil <.05µ)g/l,Colour, Taste, Odour, Iron<.2mg/l, Manganese<2mg/l, Algal toxins, fluoride<0.8mg/l Slow sand filtration Roughing filtration Plain sedimentation for >8 days Aeration Turbidity, Algae,Colour, Taste, Odour, Iron, Manganese, Algal toxins, Fluoride

9. Turbidity< average of 60 NTU and maximum up to 500 NTU, Algae (Chlorophil <.05µ)g/l,Colour, Taste, Odour, Iron<.2mg/l, Manganese<2mg/l, Algal toxins(high), fluoride<0.8mg/l Slow sand filtration Roughing filtration Granular Activated carbon Plain sedimentation for 8 days Aeration/Ozonation

10. SLOW SAND FILTER Filter Bed No. 1 To Storage Influent Structure Collection Pipes Filter Bed No. 2 A Sand Perforated Pipe Scrape off the top 2-5cm sand layer for cleaning after clogging Timber planks should be used to move on sand bed Collection Manifold Water Section A

24. RRPN Ratnayake

25. RRPN Ratnayake

27. Floating intake

28. One square kilo meter of 1 meter thick humus layer can store about 400,000 cubic meters of rainwater