Assignment 1 3bi - Hasif

8/11/2019 Assignment 1 3bi - Hasif

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3bi) Non Revenue Water (NRW) is defined as the difference between supplied water

from water treatment plant and metered quantity to the consumers. NRW components

consist of physical and commercial losses (water consumed but gives no revenue). The

causes which led to a significant increase in NRW for Perlis state are :

Commercial Loss

Inaccurate meter reading (quantity showed by the old meters is less than the

actual).

Water theft by illegal tappings

Maintenance of the water supply system through pipe flushing after leakage

repair works, reservoirs cleaning and fire brigade usage.

Physical loss

If physical loss could be solved, then operation cost could be reduced. However, for

commercial reduction, it will only recover back all the unbilled quantity and this will give

immediate impact on the revenue due to increase on collection from consumers.

Physical loss is due to the following factors:-

Pipe burst

Leakage (particularly the old asbestos cement pipe);

From the factors stated above, main reason of high physical loss in the whole country

is identified to be caused by leakage of old and dilapidated AC pipes.


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3bii) The factors that contributed to the increase NRW on Perlis are Perlis Indera

Kayangan is the smallest state in Malaysia. It is located in the north of Peninsular

Malaysia and is bordered by Thailand to the north, and Kedah. The capital of Perlis is

Kangar which is also the administrative center of the state of Perlis.

Perlis is very famous for the beauty of the quiet atmosphere undisturbed by the very

rapid development. the beauty of the Vast rice fields in the morning like a green

landscape to meet as far as the eye can see. Upon harvest, the green is covered with

golden rice is ready for harvest.

Perlis has a tropical monsoon climate and the temperature is uniform in the range of 21

degrees C to 32 degrees C, while the weather is usually dry and hot with the humidity in

the Lowlands between 82% to 86%. Average annual rainfall of the state is around 2500

mm with the most wet months from May to December. Best Time to Visit While you can

visit all year round Perlis, but it is better to avoid visiting Perlis in the wettest months,

from May to December. besides the Perlis State is a state priority sectors of agriculture

in everyday community activities.


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3biv) Method of controlling the leakage

There are six methods of controlling the leakage of :

a) Pressure controlling

b) controlling passive

c) sounding

d) district metering

e) combine metering

five of these methods involve the detection of leaks and another method involving

pressure control are accounted for as an aid to other methods

pressure control

- The effect of pressure on the rate of leakage is common in the distribution system

where it gives a great effect on the total leakage.

- Most of the distribution system to operate at optimum pressure and in some systems,

the pressure cannot be reduced without causing supply problems everywhere.

- The problem will be even greater when the pipes used were too long and would be the

crust.

- Stress reduction can be achieved in various ways, among the methods commonly

used is

-zoning

-reducing pumping head

-break pressure tank

-pressure reducing valves

zoning

- The most simple and inexpensive to reduce stress

- Only suitable for a limited area.

- Consist of closing valves are installed in the distribution system and the area where

the water is supplied from an existing water storage.


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Comprehensive repair leak

Work activities is important for reducing the rate of water loss, in addition to improving

the quality of water supply services and will restore the confidence of consumers.

Frequency of repair can be accomplished in several ways:

a) Increase workforce in repairs

b) Improving monitoring and surveillance

c) Provision of incentives to contractors who managed to give productivity high

d) Fines / Penalties apply if the contractor fails to meet targets NRW reduction

e) Accurate and complete reporting

Increased Availability of Customer Service

customer service centers in every state is better in customer complaints, including

expediting repairs leaks were reported. For example, a customer service center in

Selangor (PUSPEL).

Creation of a pool of labor for repair leaks

In addition, the workforce for leak repair competent and knowledgeable in each

Customer Service Centre is also required, especially in states with high NRW rates as

Pahang, Sabah, Kedah, Kelantan, Negeri Sembilan, Perlis and Terengganu

Existence of District Metering Zones (DMZ) / Stress Management Water

DMZ is the best way to manage NRW in an area of water distribution based on the

water flow past the inlet point to the distribution of water. Each zone is designed

encompasses 500-2000 users. Several countries have already created several DMZ,

but without proper supervision, cannot be tested task DMZ border due to open valves

and DMZ are not preserved, causing the leakage increased. Continuous monitoring is

required in a DMZ. DMZ design failure is caused by improper management of pressure

which causes the user does not receive sufficient water supply.


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Further, a DMZ that has been created should be regularly monitored and performed

maintenance. Creation of new DMZ is also required when there is an increase or

change in requirements or the use of water in the distribution system.

Conversion Pipeline is old and dilapidated

Pipe exchange involving the provision of a high number of relatively long payback. In

Malaysia, the AC pipes were adopted because many expected resistance for 70 years.

However, due to environmental factors and the factors surrounding development,

endurance pipe may be reduced.

Training and Audit Implementation Of Formula Water Balance

Balance Water formulas produced by the International Water Association (IWA) is a

guide that is very useful in calculating the Water Balance for each state. However, each

component of the Water Balance in the table has a different interpretation of the various

parties in addition to the lack of understanding in the use of these tables. Too many

assumptions are made in respect of the use of tables Water Balance render the

information given is incorrect.

Accordingly, a method needs to be established to ensure the standardization of the

definition and calculation method of each component in the table on the Water Balance

apart from the activities of a holistic NRW program described above in an effort to

reduce NRW in the country.

Training and audit implementation of water supply is one of the methods required in the

use of the Water Balance of the table.

Documents

Assignment 1 3bi - Hasif