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Case Study

RURAL WATER SUPPLY PROJECT

Name: H.K.R.MADUSHANKA

Index No: 080291 L

Course: BSc.Eng (Level 4)

Date of Sub: 14-03-2012



Introduction

With the aim of developing a water supply scheme for rural community a village named

digawewa in remote area of Polonnaruwa district is selected for the purpose of case study.

Water is an essential need of human being and wholesome supply of water is essential for the

development of rural community.

For this village, the following steps were carried out in the case study:

Scope and Objectives

About the community

Demand assessment

Proposal of water supply schemes

Evaluation of implementation, operation and maintenance cost

Benefits and Sustainability Analysis

In Digawewa, we have considered to take necessary steps to develop a self-contained scheme

working independently from National water supplies.

Scope and Objective

Water supply scheme with reliable, safe and sufficient outcome targeting the low income

people in the community.

People in this village do not have a reliable water supply scheme and they have to face much

more trouble to find water in the dry season. They have to spend their time on finding water

and it causes many financial problems. Also the hygiene of the water plays a major role.

Acknowledge the people in the rural society about the maintenance, hygiene and sanitation

education, water quality surveillance.

As the water scheme is being developed, the village people should be given sufficient

knowledge on water supply and sanitation. As most of the people are poorly literate, it is

necessary to provide a basic knowledge for the long term benefits and an efficient use of water

schemes.



Developing a self-contained water scheme within the village

Meanwhile providing a main water supply scheme, it would be desirable to have an alternate

self-contained water scheme as a backup. It can be developed later if the demand would get

higher or the supply time can be increased.

About the community….

Digawewa is a remote village located on plain land surrounded by rock outcrops and few

abandoned lakes, which are completely dried out in dry season and no proper supplying

methods are implemented.

The population of the village is nearly three thousand.

The main occupation of the people is farming.

This region receives rain during the North-East monsoon rain.

The village is 155m above sea level and no major rivers flowing in close proximity.

The water table at the village in at an average depth of 20m.

Rapid urbanisation has huge impact on these rural areas as larger cities attract many people

hoping to find work and better infrastructure and services. This process further increases the

pressure on infrastructure and services within the cities, but also poses problems to the rural

areas as they are quickly losing workers, knowledge and experience. This village too faces

migrant population to city areas and abandoning the village.

Considering the economic background of the community, most of the families are poor and

lower middle class.

The major source of income is agriculture and farming.

There is a local clinic in the village with four beds and basic treatments were given. There is anAyurveda centre as well.

Health and hygienic facilities of people also are at a low level.



Demand assessment

Water consumption can be categorised as household use and of the river, well site’s use

respectively. Currently water carried and used in the house, has been estimated at 120 litres per

house per day, or an average use of 30 litres per capita. In addition, it has been estimated that

households use an additional 50 percent of that volume of water outside the house for washing

and bathing in the river and the well. Thus the total current water consumption is, therefore,

estimated at 45 litres per capita per day.

Other than that following places are considered…

School: 600x 2.5 = 1500 litres per day

Hospital: 250x4 = 1000 litres per day

Shops: = 2000 litres per day

Private building = 1000 litres per day

As this is regarding a water supply scheme we do not consider the agricultural aspects. They

have water for agriculture by monsoon rains and rivers.

Demand calculations for Future

The design life of the water scheme to be developed is assumed to serve for ten years.

Population and demand forecast for the project in ten years are calculated and summarized

as below:

Population at the end of design period T,

Current population: Po = 3000

Population growth rate: r =0.009

P =Po + PorT

=3000 + 3000x0.009x10=3270



o Water demand of population =3270x 45

=147,150 litres per day

Assumptions

current consumption of water per day at household will have no significant changes

population growth rate for the oncoming ten years will remain constant.

Using the same procedure…

User Category No of UnitsPer unit consumption

per day (l)Total (l)

Domestic 5450 45 147150

School 1 2200 2,200

Hospital 1 1320 1,320

Temples 1 1500 1,500

Others - - 3,300

Net Total 155,470

Assumptions

There will be an increment of 15% of the current usage over the end of ten years.

Technical options available

Ground water well

In most of the countries ground water wells are used as a reliable water supply source. In this lower

end of the intake pipe is fitted with strainer and pump is located at the top. Depth of the ground water

well will vary with the depth of the water table. Here no need to treat water. Since quality of ground

water is good. Also we have found that in this area there is no CaCO3 and MgCO3 diluted with water.

So, there is no hardness in water.



Communal hand pumps (one hand pump for ten families):

Hand pumps are manually operated pumps; they use human power and mechanical advantage to move

fluids or air from one place to another. They are widely used in every country in the world for a variety

of industrial, marine, irrigation and leisure activities. As the water table of digawewa lies 20m below,

deep wells can be recommended. Deep well hand pumps are used for high lifts of more than 15 m.

Advantages and disadvantages:

The installation, maintenance and repair of deep well hand pumps is more complicated .

The centralized maintenance structure would cause problems in hand pump programs, and that

maintenance at the village level should be well planned.

Endurance in the field, and cost effectiveness will increase the effectiveness of system.

Due to improper sanitation and the lack of awareness can lead to contamination.

Inadequate supply of water.

A small piped system

There is an existing pipe line system provided from National water supply board which

draws water from a branch of Yodha ela. Due to poor maintenance and drying out of

river at the water extraction point, this system is not properly functioning.

Rainwater harvesting

Rainwater harvesting is the accumulating and storing of rainwater for reuse before it

reaches the aquifer. It has been used to provide drinking water, water for livestock,

water for irrigation, as well as other typical uses.



Capital and Operation and Maintenance cost

Operation and Maintenance (O&M)

The most obvious indicator of sustainability is the ongoing operation and maintenance of the

system. O&M is. an integrating process which draws on community participation, health

education, financing, and management as well as the technical skills required to repair WS&S

facilities. Systems which are successfully operated and maintained are, in fact, being sustained

since all of the foregoing processes must be successfully in place for this to happen.

Studies of the sector often list O&M as the second biggest problem area after inadequate

financing (WHO 1989). Both donors and country institutions give too little attention to O&M,

prefering to believe that constructing new projects is more worthy of support than maintaining

existing ones.

When systems are not maintained, most often the fault lies with poor O&M management

rather than technical incompetence. While community-managed systems are increasingly being

promoted by donors and governments, there are, in fact, large variations among countries in

the locus of responsibility. Vaying degrees of control may be shown by communities, national

agencies, regional agencies, and the private sector (Roark et al. 1993). Some countries see

water supply and sanitation as a public good that only the state can provide. Others advocate

communities taking on much of the burden of overextended government agencies. More

typically, responsibility is divided among several or all of these institutions.



Benefits of providing water supply

Economical benefits

Time of collecting water will be saved, so that villagers can use this time in useful activities.

Because the improvement in health of the society cost for medicine will be saved.

Capital and O & M costs for domestic storage will be low.

Agricultural activities of area will be promoted.

Social benefits

Due to quality of water health of people will be increased that increase the life time of people

Time children can spend on study will be increased that leads to educated society.

The stress in mind of people, about collecting water will be vanished.

Crashes between families related to water problems will be minimized.

Improvement of social affaires

Guide people to one target.

Sustainable analysis

Identifying and assessing the target population:

Understanding the knowledge, attitudes, and practices of the target population:

Involving the beneficiaries and other stakeholders in the project design:

Ensuring the commitment of national institutions to the project:

Review the resources of regional authorities in charge:

Reviewing community management resource:

Emphasizing training to local authorities at all levels:

Ensuring that beneficiaries are educated In all the benefits they will receive:

Ensuring financial viability:

Devising an acceptable cost-sharing formula:



Publicizing project accomplishments to build support:

Recognizing the developmental limits of the natural resource base:

A usage level of at least 50 percent is considered acceptable. The use of water supply facilities

will vary during the year, depending on the availability of alternative sources of supply. The

50 percent level is defined as the average for the year. It is unrealistic for various reasons

(social, financial, design) to expect the entire targeted population to be using the facilities.

At least 75 percent of the WS&S systems should be in operational order at any given time.

The acceptable operational level is higher than the usage level because maintenance and repair

depend upon standards that can be readily defined, whereas consumer behaviour is less

predictable. All mechanical systems will need occasional repairs and be out of commission for

some period of time.

At least 75 percent of management committees should be meeting periodically and carrying

out agreed upon tasks. The management committees should be carrying out their duties

regarding O&M, accounting,monitoring, and evaluation. Their most important task is to

provide overall leadership to maintaincolnrnunity support of the system and to ensure that

funds for O&M are adequate.

Repair persons may come from the government or from the private sector. Government

employees must have an adequate budget and reliable transportation. Private mechanics must

have an assured market for their services and be paid an acceptable fee. Spare parts may be

provided by either the government or private sector but must be located conveniently to the

users.

Reference

Water and Sanitation for health project-1994 – U.S Agency for international development

http://en.wikipedia.org/wiki/Hand_pump

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