WATER RESOURCES AND QUALITY

Water , water, everywhere …

Water is one of the most vital natural resources for all life on Earth. The availability and quality of water always have played an important part in determining not only where people can live, but also their quality of life. Even though there always has been plenty of fresh water on Earth, water has not always been available when and where it is needed, nor is it always of suitable quality for all uses. Water must be considered as a finite resource that has limits and boundaries to its availability and suitability for use.

The balance between supply and demand for water is a delicate one. The availability of usable water has and will continue to dictate where and to what extent development will occur. Water must be in sufficient supply for an area to develop, and an area cannot continue to develop if water demand far outstrips available supply. Further, a water supply will be called upon to meet an array of off stream uses (in which the water is withdrawn from the source) in addition to in stream uses (in which the water remains in place).
Read more: Uses of Water - building, river, oceans, important, largest, plants, source, human http://www.waterencyclopedia.com/Tw-Z/Uses-of-Water.html#b#ixzz20etXQ8TN

1.1.2 Raw Water Source

Water covers 75% of the surface of the earth. Fresh water makes up only 3% of the water on the planet. Of the fresh water, 80% is in the form of ice, 19% is underground, and 0.7% is found in the atmosphere. Because of this, only the remaining 0.3% of fresh water is surface water in earth.

What is surface water?

Surface water is the easiest water to understand because we see it every day. It is any water that travels or is stored on top of the ground. This would be the water that is in rivers, lakes, streams, reservoirs, even the oceans--even though we can't drink salt water.

Sometimes surface water sinks into the ground and becomes ground water. We visited a few water facilities and each one mentioned runoff. Runoff is the water that runs in gutters, off roofs, and out of mall parking lots when it rains. This is surface water, too. Runoff is a problem because it carries bad things like car oil, road salt, and trash into the water supply.

Surface water is treated before it becomes drinking water. This is done because things like leaves, fish, animal droppings, and boat fuel can easily get into lakes, streams, and rivers. Surface sources, such as

Ponds and lakes;

Streams and rivers;

Storage reservoirs; and

Oceans, generally not used for water supplies, at present.

What is ground water?

Ground water is a little harder to understand than surface water because you can't actually see this water. Any water that is underground is groundwater. In the water cycle, some of the precipitation sinks into the ground and goes into watersheds, aquifers and springs. The amount of water that seeps into the ground depends on how steep the land is and what is under ground. For example: places that have lots of sand underground will allow more water to sink in than ones that have lots of rock.
When the water seeps down, it will reach a layer of ground that already has water in it. That is the saturated zone. The highest point in the saturated zone is called the water table. The water table can raise and lower depending on seasons and rainfall.
Groundwater flows through layers of sand, clay, rock, and gravel. This cleans the water. Because groundwater stays underground, things that fall into surface water can't fall into it. This means that groundwater stays cleaner than water on the surface. It has its problems, too. When farmers use fertilizers and insecticides, rain will wash them into the soil where they get into aquifers [groundwater]. Gas stations have big, underground tanks where they keep the gas. If these leak, the gas sinks into the groundwater, too. Groundwater doesn't need as much treatment as surface water, but it usually gets some because of these problems.

Sub-surface sources or underground sources, such as

Springs;

Infiltration wells ; and

Wells and Tube-wells.

1.2 Water Quality Characteristics

The raw or treated water is analysed by testing their physical, chemical and bacteriological characteristics:

Physical Characteristics:

Turbidity
Turbidity is the measure of relative clarity of a liquid. It is an optical characteristic of water and is an expression of the amount of light that is scattered by material in the water when a light is shined through the water sample. The higher the intensity of scattered light, the higher the turbidity. Material that causes water to be turbid include clay, silt, finely divid ed inorganic and organic matter, algae, soluble colored organic compounds, and plankton and other microscopic organisms.

Turbidity makes water cloudy or opaque. During a rainstorm, particles from the surrounding land are washed into the river making the water a muddy brown color, indicating water that has higher turbidity values. Also, during high flows, water velocities are faster and water volumes are higher, which can more easily stir up and suspend material from the stream bed, causing higher turbidities.

If a large amount of suspended solids are present in water, it will appear turbid in appearance. The turbidity depends upon fineness and concentration of particles present in water.
Originally turbidity was determined by measuring the depth of column of liquid required to cause the image of a candle flame at the bottom to diffuse into a uniform glow. This was measured by Jackson candle turbidity meter. The calibration was done based on suspensions of silica from Fuller's earth. The depth of sample in the tube was read against the part per million (ppm) silica scale with one ppm of suspended silica called one Jackson Turbidity unit (JTU). Because standards were prepared from materials found in nature such as Fuller's earth, consistency in standard formulation was difficult to achieve.

These days turbidity is measured by applying Nephelometry, a technique to measure level of light scattered by the particles at right angles to the incident light beam. The scattered light level is proportional to the particle concentration in the sample. The unit of expression is Nephelometric Turbidity Unit (NTU). The MS values for drinking water is 10 to 25 NTU.

Colour

Dissolved organic matter from decaying vegetation or some inorganic materials may impart colour to the water. It can be measured by comparing the colour of water sample with other standard glass tubes containing solutions of different standard colour intensities. The standard unit of colour is that which is produced by one milligram of platinum cobalt dissolved in one litre of distilled water. The MS value for treated water is 5 to 25 cobalt units

Highly colored water has significant effects on aquatic plants and algal growth. Light is very critical for the growth of aquatic plants and colored water can limit the penetration of light. Thus a highly colored body of water could not sustain aquatic life which could lead to the long term impairment of the ecosystem. Very high algal growth that stays suspended in a water body can almost totally block light penetration as well as use up the dissolved oxygen in the water body, causing a eutrophic condition that can drastically reduce all life in the water body. At home, colored water may stain textile and fixtures and can cause permanent damage.

Taste and Odour

Odour depends on the contact of a stimulating substance with the appropriate human receptor cell. Most organic and some inorganic chemicals, originating from municipal or industrial wastes, contribute taste and odour to the water. Taste and odour can be expessed in terms of odour intensity or threshold values. A new method to estimate taste of water sample has been developed based on flavour known as 'Flavour Profile Analysis' (FPA). The character and intensity of taste and odour discloses the nature of pollution or the presence of microorganisms.

Temperature

The increase in temperature decreases palatability, because at elevated temperatures carbon dioxide and some other volatile gases are expelled. The ideal temperature of water for drinking purposes is 5 to 12 °C - above 25 °C, water is not recommended for drinking.

Temperature is also important because of its influence on water chemistry. The rate of chemical reactions generally increases at higher temperature. Water, particularly groundwater, with higher temperatures can dissolve more minerals from the rocks it is in and will therefore have a higher electrical conductivity. It is the opposite when considering a gas, such as oxygen, dissolved in the water. Think about how much bubblier a cold soda is compared to a warm one. The cold soda can keep more of the carbon dioxide bubbles dissolved in the liquid than the warm one can, which makes it seem fizzier when you drink it. How warm stream water is can affect the aquatic life in the stream. Warm water holds less dissolved oxygen than cool water, and may not contain enough dissolved oxygen for the survival of different species of aquatic life. Some compounds are also more toxic to aquatic life at higher temperatures. (Source: A Citizen's Guide to Understanding and Monitoring Lakes and Streams)

Solids

The sum total of foreign matter present in water is termed as 'total solids'. Total solids is the matter that remains as residue after evaporation of the sample and its subsequent drying at a defined temperature (103 to 105 °C).
Total solids consist of volatile (organic) and non-volatile (inorganic or fixed) solids. Further, solids are divided into suspended and dissolved solids. Solids that can settle by gravity are settleable solids. The others are non-settleable solids. MS acceptable limit for total solids is 500 mg/L and tolerable limit is 3000 mg/L of dissolved limits.

Chemical Characteristics:

pH

The pH of water determines the solubility (amount that can be dissolved in the water) and biological availability (amount that can be utilized by aquatic life) of chemical constituents such as nutrients (phosphorus, nitrogen, and carbon) and heavy metals (lead, copper, cadmium, etc.) pH value denotes the acidic or alkaline condition of water. It is expressed on a scale ranging from 0 to 14, which is the common logarithm of the reciprocal of the hydrogen ion concentration. The recommended pH range for treated drinking waters is 6.5 to 8.5.

Excessively high and low pHs can be detrimental for the use of water. High pH causes a bitter taste, water pipes and water-using appliances become encrusted with deposits, and it depresses the effectiveness of the disinfection of chlorine, thereby causing the need for additional chlorine when pH is high. Low-pH water will corrode or dissolve metals and other substances.

Acidity

The acidity of water is a measure of its capacity to neutralise bases. Acidity of water may be caused by the presence of uncombined carbon dioxide, mineral acids and salts of strong acids and weak bases. It is expressed as mg/L in terms of calcium carbonate. Acidity is nothing but representation of carbon dioxide or carbonic acids. Carbon dioxide causes corrosion in public water supply systems.

Alkalinity

The alkalinity of water is a measure of its capacity to neutralise acids. It is expressed as mg/L in terms of calcium carbonate. The various forms of alkalinity are (a) hydroxide alkalinity, (b) carbonate alkalinity, (c) hydroxide plus carbonate alkalinity, (d) carbonate plus bicarbonate alkalinity, and (e) bicarbonate alkalinity, which is useful mainly in water softening and boiler feed water processes. Alkalinity is an important parameter in evaluating the optimum coagulant dosage.

Hardness

If water consumes excessive soap to produce lather, it is said to be hard. Hardness is caused by divalent metallic cations. The principal hardness causing cations are calcium, magnesium, strontium, ferrous and manganese ions. The major anions associated with these cations are sulphates, carbonates, bicarbonates, chlorides and nitrates.

The total hardness of water is defined as the sum of calcium and magnesium concentrations, both expressed as calcium carbonate, in mg/L. Hardness are of two types, temporary or carbonate hardness and permanent or non carbonate hardness. Temporary hardness is one in which bicarbonate and carbonate ion can be precipitated by prolonged boiling. Non-carbonate ions cannot be precipitated or removed by boiling, hence the term permanent hardness.

If the water is relatively hard, you may notice that it is difficult to get a lather up when washing your hands or clothes. And, industries in your area might have to spend money to soften their water, as hard water can damage equipment. Hard water can even shorten the life of fabrics and clothes!

Definition

Calcium Carbonate Concentration

Soft Water

0 – 60 milligrams per liter (mg/L)

Moderately Hard

61 – 120 mg/L

Hard

121 – 180 mg/L

Very Hard

181 or above

Chlorides

Chloride ion may be present in combination with one or more of the cations of calcium, magnesium, iron and sodium. Chlorides of these minerals are present in water because of their high solubility in water. Each human being consumes about six to eight grams of sodium chloride per day, a part of which is discharged through urine and night soil. Thus, excessive presence of chloride in water indicates sewage pollution. MS value for drinking water is 250 to 1000 mg/L.

Sulphates

Sulphates occur in water due to leaching from sulphate mineral and oxidation of sulphides. Sulphates are associated generally with calcium, magnesium and sodium ions. Sulphate in drinking water causes a laxative effect and leads to scale formation in boilers. It also causes odour and corrosion problems under aerobic conditions. Sulphate should be less than 50 mg/L, for some industries. Desirable limit for drinking water is 150 mg/L. May be extended upto 400 mg/L.

Iron

Iron is found on earth mainly as insoluble ferric oxide. When it comes in contact with water, it dissolves to form ferrous bicarbonate under favourable conditions. This ferrous bicarbonate is oxidised into ferric hydroxide, which is a precipitate. Under anaerobic conditions, ferric ion is reduced to soluble ferrous ion. Iron can impart bad taste to the water, causes discolouration in clothes and incrustations in water mains. MS value for drinking water is 0.3 to 1.0 mg/L.

Nitrates
Nitrates in surface waters occur by the leaching of fertilizers from soil during surface run-off and also nitrification of organic matter. Presence of high concentration of nitrates is an indication of pollution. Concentration of nitrates above 45 mg/L cause a disease methemoglobinemia. MS value is 45 mg/L.

Bacteriological Characteristics:

Bacterial examination of water is very important, since it indicates the degree of pollution. Water polluted by sewage contains one or more species of disease producing pathogenic bacteria. Pathogenic organisms cause water borne diseases, and many non pathogenic bacteria such as E.Coli, a member of coliform group, also live in the intestinal tract of human beings. Coliform itself is not a harmful group but it has more resistance to adverse condition than any other group. So, if it is ensured to minimize the number of coliforms, the harmful species will be very less. So, coliform group serves as indicator of contamination of water with sewage and presence of pathogens.

Drinking Water Contaminants.

Clean fresh drinking water is needed by every person on the planet for life, and water is by far the most important nutrient for the human body (besides oxygen). Just how important is water to people? Well over 60 % of our physical being is composed of it, and most experts believe that we cannot survive more than 2-7 days without water. In contrast, people can sometimes go for weeks without eating food. Since the dawn of time, people have used their senses to filter information about their environment for life and survival. Of course, there are all types of external dangers, but we rely heavily on our sense of taste, smell, and sight when introducing things into our bodies. These sensory perceptions are very keen while we are taking a drink of water. Often, the first thing we notice is the color of the water. There are certain drinking water contaminants in our water that produce a certain discoloration. If our drinking water passes the visual test, the smell is often the next thing that catches our attention. Two common odors that are typically encountered are either a chlorine, or a sulfur smell in water. Moving on to the sense of taste, there are particularly bad tastes, such as the metallic taste of water; this means you need to remove iron from water. Lastly, and perhaps most importantly, are contaminants in our water that our senses cannot perceive. These might include bacteria, protozoan cyst, and/or viruses.

Here’s the list of types of contaminants that has to remove from municipal tap water:

1. Organic compounds (Pesticides, Herbicides, Pharmaceuticals, Fuels, etc.)
2. Toxic metals (Lead, Mercury, Aluminum, Cadmium, Chromium, Copper, etc.)
3. Bacterial and viruses (Giardia, Cryptosporidium, etc.)
4. Radioactive substances (Radon and Uranium, etc.)
5. Additives (Chlorine and Chloramines, Fluoride, etc.)

The following is a list of common water contaminants found in both public and private drinking water supplies together with their health effects and the most appropriate treatment methods for their removal.

Contaminant
Name

Maximum Acceptable Level

Common
Sources

Health
Effects

Most Effective Purification Technology

Arsenic

0.010 mg/L

Natural deposits, smelters, glass, electronics wastes, orchards

Skin, nervous system toxicity

Reverse Osmosis

Asbestos

7 MFL (million fibers / liter)

Natural deposits, asbestos cement in water systems

Cancer

Reverse Osmosis,Activated Carbon

Barium

2 mg/L

Natural deposits, pigments, epoxy sealants, spent coal

Circulatory system effects

Reverse Osmosis

Bacteria / Coliform

-

animal & human waste, septic fields, sewage, farming

various illnesses

Ultraviolet

Cadmium

0.005 mg/L

Natural deposits, galvanized pipe corrosion, batteries, paints

Kidney disorders

Reverse Osmosis

Chloradane

0.002 mg/L

Leaching from soil treatment for termites

Cancer

Activated Carbon

Chlorine

4 mg/L

Water disinfection

see chlorination by-products (Trihalomethanes)

Activated Carbon, KDF

Chromium-6

0.1 mg/L

Natural deposits, mining, electroplating, pigments

Liver, kidney, circulatory disorders

Reverse Osmosis

Copper

1.3 mg/L

Natural / industrial deposits, wood preservatives, plumbing

Gastrointestinal irritation

Reverse Osmosis, KDF

Cryptosporidium

Zero

Animal or human waste, contaminated food products

Gastrointestinal illness

Reverse Osmosis,Carbon Block (0.5 micron)

E.coli

Zero

Naturally occurring, human or animal wastes

Gastrointestinal disorders (often severe)

Ultraviolet

Fluoride

4 mg/L

Natural deposits, fertilizer, aluminum industries, water additive

Skeletal and dental fluorosis

Reverse Osmosis

Giardia

Zero

Naturally occurring, human or animal wastes

Gastrointestinal disorders (Beaver Fever)

Reverse Osmosis,Carbon Block (0.5 micron)

Hydrogen Sulfide

n/a

Natural deposits

Rotten egg taste and odour

Manganese Greensand Filter, KDF

Iron

0.3 mg/L

Natural deposits

Staining of laundry, plumbing, appliances

Iron Reduction Filter

Manganese

0.05 mg/L

Natural deposits

Staining of laundry, plumbing, appliances

Iron Reduction Filter

Mercury

0.002 mg/L

Crop runoff, natural deposits, batteries, electrical switches

Kidney, nervous system disorders

Reverse Osmosis,Activated Carbon

Microbiological Contaminants

-

animal & human waste, septic fields, sewage, farming

various illnesses

Various

Nitrate / Nitrite

10 mg/L

Animal waste, fertilizer, natural deposits, septic tanks, sewage

Methemoglobulinemia (blue baby syndrome)

Reverse Osmosis

PCB

10.0005 mg/L

Coolant oils from electrical transformers, plasticizers

Cancer

Activated Carbon

Radium

5 pCi/L

Natural deposits

Bone cancer

Reverse Osmosis

Radon

Natural deposits

Cancer

Activated Carbon

Selenium

0.05 mg/L

Natural deposits, mining, smelting, coal/oil combustion

Liver damage

Reverse Osmosis

Sulfate

500 mg/L

Naturally-occurring

laxative effect - gastrointestinal irritation (loose stools, diarrhea, etc.) especially in infants or individuals not acclimated to high levels

Reverse Osmosis

Total Dissolved Solids

500 mg/L

Erosion of naturally occurring mineral deposits

Gastrointestinal irritation in some individuals

Reverse Osmosis

Toxaphene

0.003 mg/L

Insecticide formerly used on cattle, cotton, soybeans

Cancer

Activated Carbon

Trihalomethanes (THMs)(chlorination by-products)

0.08 mg/L

By-product of chlorination in drinking water

Cancer

Activated Carbon, KDF

Turbidity

n/a (5 NTU max. recommended)

Soil runoff

Interferes with disinfection, filtration

Whole-House Sediment Filter, Reverse Osmosis

Uranium

0.03 mg/L

Natural occurring

Kidney disorders, cancer

Reverse Osmosis

Viruses

-

animal & human waste, septic fields, sewage, farming

various illnesses

Ultraviolet

Volatile Organic Compounds (VOCs)

Varied

Varied

Varied, incl. cancer

Activated Carbon

Zinc

5 mg/L

Natural deposits, industrial waste

Metallic taste in water

Reverse Osmosis, KDF

Please note: This list was compiled for research and informational purposes only. It is not intended to suggest that any of the listed contaminants are present in your water supply. Only testing by an accredited lab can identify the presence of contaminants in your water supply.

1.5 Policy and regulation

The legal framework for the water and sanitation sector differs between peninsular Malaysia (with its 11 federal states and two federal territories) on the one hand and Eastern Malaysia (with the federal states Sabah and Sarawak and one federal territory) on the other hand. While a water reform was enacted for peninsular Malaysia in 2006, the previous legal and institutional framework was maintained in Eastern Malaysia.

Two main laws passed in 2006 from the legal framework of the water and sanitation sector in peninsular Malaysia. The Water Services Industry Act (WSIA) established a national water asset holding company called PAAB and a Water Forum to give voice to hitherto under-represented stakeholders such as consumers. The National Water Services Commission Act established a National Water Services Commission known under its Malay acronym as SPAN. The acts separated the functions of policy making (government), regulation (SPAN), asset ownership (PAAB) and service provision (state water companies) from each other. The laws were enacted after extensive public consultations over two years. As part of the reform process, for the first time in Malaysian history a draft bill had been made available for public discussion before it was presented to Parliament.

SPAN now issues licenses for water operators, mainly state water companies. These licenses can theoretically be revoked if key performance indicators are not met or other standards are not respected. The standards are set and monitored by SPAN.

In Eastern Malaysia water supply remains a responsibility of state governments and sanitation a responsibility of local governments.

Within the executive branch of the federal government, the Ministry of Energy, Green Technology and Water is in charge of setting water supply and sanitation policies. It is assisted by two technical agencies under its supervision: The water supply department (JBA) and the sewerage services department (JPP). The latter was established through the Sewerage Services Act of 1994 as a regulatory agency for the private sanitation company IWK. When IWK was taken over by the government in 2000, the sewerage services department became responsible for the development of infrastructure while IWK remained in charge of operation and maintenance as a publicly owned company. The regulatory functions of JPP ceased in 2007.

Malaysian Laws & Regulations

Parliamentary Acts

» National Policies of Government of Malaysia - Third National Agricultural Policy (1998 - 2010)

» Federal Constitutions

» Ministerial Functions Act (1969) (Perintah Menteri-Menteri Persekutuan 2004) : DID Role In River Management In On Flood Mitigation and River Conservancy