Local Water Supply Analysis
Gather information on the features of you local water supply in terms of:
The Catchment Area:
Sydney's water supply is made of 5 main catchments: Warragamba, Woronara, Hawkesbury Nepean, Shoalhaven and Blue Mountains. Warragamba Catchment covers 9,051km². My local area is Blacktown, in an image shown below; all the catchment areas are linked to Warragamba Catchment Area.
Possible Sources of Contamination:
Water quality in Warragamba catchment is affected by: * Wastes and runoff from industry and urban development * Poor sewage and storm water management * Agricultural activities * Mining * Fertilizers * Forestry * Chemical fuel spills * Erosion * Uncontrolled bush fires * Fallen Tree Branches …show more content…
Low DO indicates activity of aerobic microbes which use up the oxygen.
BOD is a measure of organic matter in water. High BOD is due to paper and food processing industries.
AAS is used by adding Na2S to test quantitatively for heavy metals and metal ions.
Physical and Chemical Processes used to purify water:
Physical Processes:
Screening: Water from the dam is screened by removing large contaminants.
E.g.: Fallen Trees.
Sedimentation: Allowing floc particles to settle out to form a sludge, which can be removed from settling tanks periodically.
Filtration: Water from the settling tanks is piped to filtration tanks to be filtered. The water at this stage should be clear.
Chemical Processes:
Aeration: The screened water is then sprayed into the air to increase oxygen levels so that iron salt becomes oxidised and forms insoluble salts oxides which can be removed.
Flocculation: Removes colloidal impurities. Alum (Aluminium Sulfate) is a chemical added to cause the impurities within the water to stick/thicken together forming a precipitate or floc of Al(OH)3 which would be large enough to be filtered …show more content…
Water treatment consists of removing very small particles by flocculation. The water is sand filtered to remove bigger particles. A 2m deep bed of sand is used. Finally, it is treated with chlorine to kill microorganisms as disinfection is needed to ensure concentrations are acceptably low. Water testing is carried out for ions, colour, pH, hardness, turbidity, conductivity, micro-organisms. Alternative methods of filtration such as membrane filtration may be both more efficient in removing particles including microorganisms such as Giardia and Cryptosporidium. However, these techniques are expensive to execute.
Monitoring of catchment and treatment processes is necessary. If microbial levels are too great extra chlorine can be added, if organic matter is excessive, aeration of the water and longer storage can be done to allow decomposition to occur. This means that constant monitoring and adjustment is required for the process to be
The Catchment Area:
Sydney's water supply is made of 5 main catchments: Warragamba, Woronara, Hawkesbury Nepean, Shoalhaven and Blue Mountains. Warragamba Catchment covers 9,051km². My local area is Blacktown, in an image shown below; all the catchment areas are linked to Warragamba Catchment Area.
Possible Sources of Contamination:
Water quality in Warragamba catchment is affected by: * Wastes and runoff from industry and urban development * Poor sewage and storm water management * Agricultural activities * Mining * Fertilizers * Forestry * Chemical fuel spills * Erosion * Uncontrolled bush fires * Fallen Tree Branches …show more content…
Low DO indicates activity of aerobic microbes which use up the oxygen.
BOD is a measure of organic matter in water. High BOD is due to paper and food processing industries.
AAS is used by adding Na2S to test quantitatively for heavy metals and metal ions.
Physical and Chemical Processes used to purify water:
Physical Processes:
Screening: Water from the dam is screened by removing large contaminants.
E.g.: Fallen Trees.
Sedimentation: Allowing floc particles to settle out to form a sludge, which can be removed from settling tanks periodically.
Filtration: Water from the settling tanks is piped to filtration tanks to be filtered. The water at this stage should be clear.
Chemical Processes:
Aeration: The screened water is then sprayed into the air to increase oxygen levels so that iron salt becomes oxidised and forms insoluble salts oxides which can be removed.
Flocculation: Removes colloidal impurities. Alum (Aluminium Sulfate) is a chemical added to cause the impurities within the water to stick/thicken together forming a precipitate or floc of Al(OH)3 which would be large enough to be filtered …show more content…
Water treatment consists of removing very small particles by flocculation. The water is sand filtered to remove bigger particles. A 2m deep bed of sand is used. Finally, it is treated with chlorine to kill microorganisms as disinfection is needed to ensure concentrations are acceptably low. Water testing is carried out for ions, colour, pH, hardness, turbidity, conductivity, micro-organisms. Alternative methods of filtration such as membrane filtration may be both more efficient in removing particles including microorganisms such as Giardia and Cryptosporidium. However, these techniques are expensive to execute.
Monitoring of catchment and treatment processes is necessary. If microbial levels are too great extra chlorine can be added, if organic matter is excessive, aeration of the water and longer storage can be done to allow decomposition to occur. This means that constant monitoring and adjustment is required for the process to be