Slide 1

Water Quality Criteria 1914 USA,United State Standards for Drinking Water (first issued) 1962 Safe Drinking Water Act 1968 1971 National Interim Primary Drinking Regulations (effective in 1977) Set Maximum Contaminant Level (MCls) inorganic substance, Turbidity, coliform, 6 pesticides, radionuclide standard Reduced from formal level of 5 NTU to 1 NTU 1961 WHO - European Water Guildline Water Quality for Drinking Water ( worldwide Application 1963 ) 1975 AWWA :American Waterworks Association,Water Quality Goals ( Treatment Process and Method ) 1974 Water Quality and Treatment, AWWA 1971 Repeat revised Regulation for all public water supplies Slide 2 Water Quality Criteria 1980EPA:Environment Protection Agency, impact industry THMs = 0.1 mg/l 10,000 or more persons ( require GAC ) AWWA Goals ( 1971 ) concentrate on aesthetic and other characteristics by consumer detection Filtered Water Turbidity < 0.1 NTU Color < 0.3 unit Res. Al < 0.05 mg/l Fe < 0.05 mg/l Mn < 0.01 mg/l Slide 3 WSP Preparation System Assessment Operational Monitoring Management and Communication Feedback and Improvement Plan Action Check Do Slide 4 Slide 5 Flow Chart Slide 6 Slide 7 Slide 8 Slide 9 Slide 10 Slide 11 Algae Slide 12 Slide 13 Slide 14 Diatom Slide 15 Slide 16 pH Turbidity UV254 pH Turbidity UV254 pH Turbidity UV254 pH Coagulant & pH adjustment RAPID MIX FLOCCULATOR CLARIFICATIONFILTRATION Tropical forest River catchment 1 Run-off Raw water transfer Users City 1 Water treatment Abstraction from river Distribution system Private connection Supply flow diagram Refer to C1 description Water treatment 16 Slide 17 understanding of current water quality Regulatory limit Nitrate concentration leaving works 17 Slide 18 Description and analysis, the team will have a set of maps that show: 1. the supplys primary and secondary infrastructure; 2. how many people use the water supply in different parts of the system 3. major hydraulic zones within the distribution system and thus water flows around the system; 4. areas where there is evidence of failures in water quality/safety management as a means of identifying particular areas of concern; 5. the environment within which the supply is found as a means of identifying potential hazardous areas; 6. known water quality failures within zones of the network. Distribution system Slide 19 . Catchment - Stratication ? - Eutrofication ? Treatment Process -Pretreatment ? -Additive Chemical ? Storage Tank ? Distribution ? Color Odor Fe Mn Turbidity Coliform Res.Cl 2 THM Slide 20 Colloid Van der Woals Force Brownian Movement Electrostatic Repulsive Force Slide 21 Slide 22 Coagulation & Flocculation Destabilization double layer compression charge neutralization bridging colloid entrapment Slide 23 Slide 24 Slide 25 Slide 26 Al 2 (SO 4 ) 3.18H 2 O Al(OH) 3 Al n (OH) m Cl (3n-m) (Al 6 (OH) 1 5 ) 3+ Slide 27 Slide 28 Slide 29 Slide 30 Slide 31 Jar Test Optimum pH Slide 32 Jar Test Optimum Coagulation Dose Slide 33 Filtration Tank ? Org.+inorg. ? accumulation Mudball ? Slide 34 Determination of mudball Add Attachment Slide 35 Disinfection Slide 36