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Water Resources and Quality
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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the water is withdrawn from the source) in addition to in stream uses (in which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
» Other Legislations
Land
Acts
» National Land Code 1965 And
Waters
» Land Conservation Act 1960
Flood
Mitigation
» Drainage Works Act 1954
(1988)
» Local Government Act (1976):
(Peninsular)
» Earthworks Bylaws
» Street, Drainage and
Building Act 1974 (1994)
» Town and Country Planning
Act 1976
River
Management
» Waters Act 1920 (Act 418)
& Water Supply (Federal Territory of Kuala Lumpur) Act 1998
(Act 581)
» Mining Enactment 1962
(F.M.S. Cap 147)
» Environmental Quality Act
1974 (Act 127) & Subsidiary Legislation
» Ministerial Functions Act
1969 (Act 2)
» National Forestry Act 1984 (Act
313) & Wood-Based Industries
(State Legislatures Competency) Act 1984
(Act 314)
» Fisheries Act 1985 (Act 317)
and Regulations
» Water Act 1989 - Chapter 15
» Sewerage Services Act 1993
(Act 508) & Regulations And Orders
Coastal
Management
» Town and Country Planning
Act 1976
» Environmental Quality Act
1974: (1985)
» Environmental Quality Order
1987 (Environmental Impact Assessment - Prescribed Activities)
» Mining Enactment 1936
(F.M.S. Cap 147)
» Fisheries Act 1963 (1985) /
Inland Fisheries Act
Hydrological
& Water Resources
» Drainage Works Act 1954
(1988)
» Waters Act 1920 (Cap 146)
(1989)
Urban
Stormwater
» Street, Drainage and
Building 1974 (Act 133) - Section 70A(9)
» Street, Drainage and
Building 1974 (Act 133) - Section 71
Agriculture
Drainage
» Third National Agricultural
Policy (1998-2010)
» Irrigation Areas Act 1953
(1989)
» Drainage Works Act 1954
(1988)
» Waters Act 1920 (Cap 146)
(1989)
» Fisheries Act 1963 (1985) /
Inland Fisheries Act
Acts
Year
P.U.(A)
79/2010
Water Services Industry Act 2006
Water Services Industry (Licensing) (Exemption) Order 2010
2010
P.U.(A)
161/2010
Water Services Industry Act 2006
Water Services Industry (Licensing) (Exemption) (No. 2) Order 2010
2010
P.U.(A)
1/2011
Water Services Industry Act 2006
Water Services Industry (Sewerage Capital Contribution Fund) Regulations 2011
2011
Suruhanjaya Perkhidmatan
Air Negara Act 2006 (Act 654)[P.U (B) 39/07]
2006
Water Services Industry
Act 2006 (Act 655)[P.U (B) 458/07]
2006
Water Services Industry
(Compounding Of Offences) Regulations 2008 [P.U.(A) 259/2008]
2008
Water Services Industry
(Permit) Rules 2007 [P.U.(A) 438/2007]
2007
Water Services Industry
(Licensing) Regulations 2007 [P.U.(A) 432/2007]
2007
Sewerage Services
(Charges) Regulation 1994
1994
Water Services Industry
(Rates for Water Supply Services) (State of Kedah) Regulations 2010 [P.U (A)
332/2010]
2010
Water Services Industry
(Rates for Water Supply Services) (State of Kelantan ) Regulations 2010 [P.U
(A) 333/2010]
2010
Water Services Industry
(Rates for Water Supply Services) (State of Penang) Regulations 2010 [P.U (A)
334/2010]
2010
Water Services Industry
(Rates for Water Supply Services) (State of Johor) Regulations 2010 [P.U (A)
371/2010]
2010
Water Services Industry
(Rates for Water Supply Services) (State of Malacca) Regulations 2010 [P.U
(A) 372/2010]
2010
Información
- Descripción
- This topic is to expose the student to water resources and water quality standard. Students are also exposed to the water quality parameters testing. Water parameters comply with World Health Organisation Standard
- Creado por
- Laily Tuan Mat
- Visitas
- 88
- Valoración