Water Source & Treatment PDF

Dr. Kamal Maky 12/12/2020 1  Environmental Health ) ‫َﻲ أ ََﻓَﻠَ ََﺎ‬ َّ ُ ‫ِﻦ ِ اﻟ ْْﻤ ََﺎء ﻛ‬ ٍّ َ ‫ُﻞ ﺷ ََﻲ ْ ٍْء ﺣ‬ َ ‫و ََﺟ ََﻌ َْﻠَ ْﻨ ََﺎ ﻣ‬ 30/‫ﻳ ُُﺆ ْ ِْﻣ ِﻨ ُُ...

Dr. Kamal Maky 12/12/2020 1  Environmental Health ) ‫َﻲ أ ََﻓَﻠَ ََﺎ‬ َّ ُ ‫ِﻦ ِ اﻟ ْْﻤ ََﺎء ﻛ‬ ٍّ َ ‫ُﻞ ﺷ ََﻲ ْ ٍْء ﺣ‬ َ ‫و ََﺟ ََﻌ َْﻠَ ْﻨ ََﺎ ﻣ‬ 30/‫ﻳ ُُﺆ ْ ِْﻣ ِﻨ ُُﻮنَ ( اﻷﻧﺒﻴﺎء‬ Water Source & Treatment 2 VIRONMENTAL HEALTH Water source & treatment ) ‫َﻲ أ ََﻓَﻠَ ََﺎ‬ َّ ُ ‫ِﻦ ِ اﻟ ْْﻤ ََﺎء ﻛ‬ ٍّ َ ‫ُﻞ ﺷ ََﻲ ْ ٍْء ﺣ‬ َ ‫و ََﺟ ََﻌ َْﻠَ ْﻨ ََﺎ ﻣ‬ 30/‫ﻳ ُُﺆ ْ ِْﻣ ِﻨ ُُﻮنَ ( اﻷﻧﺒﻴﺎء‬ 2nd Session online  WATER
By SOURCE & TREATMENT
Dr Kamal Maky MBBS, MHA, MD, MHPE Environmental Ass. Professor of Public Health, Com Health Medicine & Medical Education Head of Accreditation Committee-IUA- Faculty of Medicine 12/12/20 Dr. Kamal Maky 4 20 INTENDED LEARNING OUTCOMES Identify The global situation Determine the Sources of water supply Describe uses of water Identify types of wells Identify human water requirements WATER Lack of safe and wholesome water supply, can lead to ill- health, specially in developing countries, water that is easily accessible, adequate in quantity, free from contamination, safely & readily available through out the year (i.e. What is required for a state of positive health & well-being) Water is not only a vital environment life factor to all forms of life, but it has also a great role to play in socio-economic development of human population  IS THERE A WATER CRISIS? Over 1 billion people lack access to safe water 2 out of 3 people will be living with water shortages by 2025 Half of the world's wetlands have been lost since 1900. The basis for most projections for future conflicts is that with the growth of demand, the decline in freshwater availability, & the adverse health effects from poor water quality, scarcity will result in  GLOBAL Less than 3% of the world’s water is fresh - the rest is seawater and undrinkable. Of this 3%, over 70% is frozen and not available to man. Thus humanity must rely on this 0.3% for all of man’s and ecosystem’s fresh water needs  WATER REQUIREMENTS The basic physiological requirements for drinking water have been estimated at about 3 liters per head per day this is just for survival A daily supply of 150-200 liters per capita is considered as an adequate supply to meet for all urban domestic purposes The consumption of water however depends upon climate condition, standard of living and habits of the  WATER REQUIREMENTS Water must be available close to people (i.e. no spend time and energy to obtain it, which can pollute water in the process) Adequate volume will help to reduce the incidence of many water – related diseases  Water  Pure water “Water that is free from objectionable colour, odour, taste & turbidity is called pure Water  Wholesome water “Pure water which contains adequate amount of dissolved oxygen but no microorganisms and other organic pollutants and is free of microbial and chemical toxins is called wholesome water”  Safe & wholesome water Water intended for human consumption should be both safe & wholesome. This has been defined as: free from pathogenic agents free from harmful chemical substances pleasant to taste - free from color & odor usable for domestic purposes  Uses of water Domestic Drinking, cooking, washing, bathing & flushing uses Public purposes: Cleaning streets, fire protection, public parks Industrial purposes: Processing, cooling, etc WATER is therefore an essential factor in the economic, social & cultural Agricultural development of the community, through purposes: Irrigation, pasture eliminating diseases, promoting rural Power production: development & improving quality of life Steam power & hydropower Carrying away wastes: : From houses, industries 
Sources of water supply Water can be abstracted from a number of sources: 1.Rain water 2.Surface water a) impounding reservoirs b) rivers & streams c) tanks, ponds & lakes 3.Ground water a) shallow wells b) deep wells c) springs  1. Rain Rain is prime purest source of all water It contributes to all other sources of water It sinks into the ground (increases ground water) Some run into streams & rivers Some of the water in the soil is taken by plants & evaporates These events are called Water Cycle  Characteristics of rain water Purest source of water in nature Physically - clear, bright, sparkling Chemically - soft water (only traces of dissolved minerals) Biologically - free from pathogens. Impurities Can pick up suspended impurities from atmosphere e.g. dust, carbon dioxide, nitrogen oxide – acid rain water  2.Surface water A. Impounding reservoirs B. Rivers & Streams C. Tanks, ponds and lakes D. Sea water Originates from rain & is prone to get contaminated therefore it needs sanitary protection & purification before use  a) Impounding reservoirs These are artificial lakes constructed of masonry in which large quantities of water is stored. Dams built across rivers and mountain streams provide large reservoirs Characteristics: Water is clear (nearly as pure as rain water) Pathogen free Chemical free  b) Rivers Rivers furnish a dependable supply of water Many countries depend mainly on rivers for their water supply – Sudan (main source of water) Characteristics: River water turbid during rainy seasons Contains dissolved impurities (surface washing, sewage, industrial, agricultural waste) Self purification: Dilution Sedimentation Aeration & sunlight exposure  c) Tanks Tanks are large excavations in which surface water is stored. They are important source of water in some villages in Sudan. Contamination is a problem (weeds, washing in tanks, animal waste etc…) Natural purification: Storage Oxidation Aeration Sunlight exposure Dr. Kamal Maky 12/12/2020 21  Improvements of tanks  Edges should be elevated  Fence around the tank  Stop get into the tank directly  Elevated platform where people draw water  Weeds removed periodically  Tank should be cleaned at the end of the dry season  Simplest solution thought to be sand filtration & chlorination of the whole water  D) SEA WATER Plentiful source but has many great limitations It contains: 3.5% salts in solutions 30-36g/L of dissolved solids including Cl , Na & Mg Desalting & demineralization process involve heavy expenditure  3.GROUND WATER Rain water percolating into ground constitutes ground water It was recently realized that ground water is limited in the world Ground water: A. Shallow wells B. Deep wells C. Springs  3.GROUND WATER Advantages Free from pathogenic agents Requires no treatment Constant even during dry season Less subject to contamination Disadvantages High in mineral content (salts of Ca & Mg = hard water) Requires pumping  HARD WATER Water that has high mineral content (in contrast withsoft water ) Hard water minerals primarily consist of: Calcium (Ca2+), calcium carbonate in the form of chalk, limestone Magnesium (Mg2+) Metal cations Bicarbonates Sulphates Hard water is generally not harmful to one's health  SOFT WATER Contains few or no calcium or magnesium ions, as opposed to hard water which contains significant amounts of these ions Soft water usually comes from peat or igneous rock sources, such as granite but may also derive from sandstone sources, since such sedimentary rocks are usually low in calcium and magnesium  WELLS Important source of water supply Technically, wells are of two types shallow & deep Shallow wells tap sub soil water Deep wells tap water from the water-bearing stratum & are usually machine dug, they are deep & furnish the safest water  Difference between deep & shallow wells Shallow wells Deep wells Definition Taps the water from above Taps the water from below the 1st impervious layer the 1st impervious layer Chemical quality Moderately hard Much hard Bacteriological quality Often contaminated Often pure water Yield Usually goes dry in Summer Provides a constant supply Dr. Kamal Maky 12/12/2020 29  Well Contamination Microorganisms Most of the bacteria, viruses, parasites, and fungi that contaminate well water comes from fecal material from humans and other animals Common bacterial contaminants includeE. coli ,Salmonella , Shigella , andCampylobacter jejuni Common viral contaminants includenorovirus ,sapovirus , rotavirus , enteroviruses, and hepatitis A Parasites includeGiardia lamblia ,Cryptosporidium ,Cyclospora cayetanensis , and microsporidia  Chemicals Chemical contamination is a common problem with groundwater Nitrates from sewage or fertilizer Pesticides and volatile organic compounds from gasoline dry-cleaning chemicals fuel additive methyl tert-butyl ether (MTBE) perchlorate from rocket fuel, airbag inflators, and other artificial and natural sources TYPES OF WELLS Artesian wells Sanitary wells Tube wells  ARTESIAN WELLS
Artesian wells are kind of deep wells in which water rises above the level of ground water under pressure A well drilled through impermeable strata to reach water capable of rising to the surface by internal hydrostatic pressure. SANITARY WELLS
A sanitary well is one which is properly located, well constructed & protected against contamination with a view to yield a supply of safe water Location: 15m or more away from any likely source of contamination not more than 100m far from users TUBE WELLS
They yield safe water & cheap in comparison to other sources Largest use in rural community The tube well consist of pipe sunk into the water-bearing stratum and fitted with a strainer at the bottom, and a hand pump at the top An average well may last for a period of 5 to 10 years Some tube wells have given satisfactory service even after 30 years SPRINGS When ground water comes to the surface & flows freely under natural pressure, it is called a (spring) Shallow ones dry quickly during summer Deep springs do not show seasonal fluctuations Springs do not need pumping Exposure to contamination is high  NKS THA