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CHAPTER 1

INTRODUCTION Water for human consumption comes from one of two basic sources: Water from a well to supply an individual residence, well water for farmstead properties, and well water for small public sector properties that include schools, public buildings, and small commercial enterprises. Municipal water systems that provide potable water to a wide array of commercial property and domestic use buildings including apartments, condominium, duplex housing and single family dwellings. Understanding the fundamentals of a municipal water supply delivery system is essential to closely examining the many features of a water system and the many options in designing a water delivery system. Chapter 1 provides a basic overview of: 1) 2) 3) 4) 5)

The Anatomy of a Water System The Need for a Continuously Available Water Supply Considerations for Establishing Municipal Water Supply Systems Classification of Water Supply Sources The Classification of Water Supply Systems

The purpose of municipal water delivery systems is to transport potable water from a water treatment facility to residential consumers, for use as drinking water, water for cooking, water for sanitary conditions, and other water use in a domestic environment. Water supply also is essential for business and industry to operate in a municipal environment. Of no less importance is the need to supply water to properly located fire hydrants to provide the public with an effective level of fire protection. Municipal water systems also may need to provide water for special services that include street cleaning, the selling of water to contractors for erecting buildings, parks and recreation, and miscellaneous uses. A water system has two primary requirements: First, it needs to deliver adequate amounts of water to meet consumer consumption requirements plus needed fire flow requirements. Second, the water system needs to be reliable; the required amount of water needs to be available 24 hours a day, 365 days a year.

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Figure 1-1 illustrates a progressive view of the water system. Two holding reservoirs supply water to a treatment plant that processes the water to remove impurities and adds chemicals to bring the water into compliance with the Environmental Protection Agency (EPA) regulations on clean water for drinking and commercial cooking. The actual water treatment process is discussed. The purified water, or finished water, then is pumped to several different storage tanks and storage basins around the city for release into the distribution system piping network on demand for consumer use or in the case of a working fire. Depending on the different elevations points throughout the city, additional pumping stations are provided to maintain adequate pressure in the water system during varying periods of consumer use or emergency waster supply demand requirements. Water flows from the storage locations through the primary, secondary, and distributor mains to supply service lines to individual water consumers and lateral lines to supply fire hydrants. Figure 1-1: Features of a Small Community Water Distribution System

2 Figure 1-1: Features of a Small Community Water Distribution System

Water Distribution System Water distribution systems are designed to adequately satisfy the water requirements for a combinations of the following demands: 1) Domestic 2) Commercial SITS-CIVIL

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3) Industrial 4) Fire-fighting The system should be capable of meeting the demands at all times and at satisfactory pressure The main elements of the distribution system are: i) ii) iii) iv) v) vi) vii)

Pipe systems Pumping stations Storage facilities Fire hydrants House service connections Meters Other appurtenances Components of Water Supply System

Figure 1-2:components of water supply system. To manage and control WDS we need to create Geo database and knowledge-base in order to store water background data layers with features in ArcGIS and manage WDS Therefore, GIS is comprehensive and multifunctional computer-based software being used in water transmission and distribution systems in modern and systematic water supply. However, it is the best application to manage, manipulate and maintain geospatial data and to develop and sustain asset management for today's water utilities in worldwide. Though for the targeted area there was no previous data available on water supply, no distribution lines, and service connection information as well as with no service population and sewerage system network the entire situation is unmapped. SITS-CIVIL

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We have produced three hierarchical Geo-databases separately. The Geo-database structures indicate main, geometric network and topology Geo-databases consisted of feature data sets. Water supply background data (vector data and raster data) collected from various source that working for shoulder to shoulder for vanasthalipuram zone of hydeabad city water supply extension. We designed a proper WDS created in GIS then imported to EPANET to be analysed and simulated in order to approach the objectives and successful consequences. The commonly network has been contained of physical and non-physical components and features such as pipes, nodes and reservoir and nonphysical describes the behavior and operational aspects of a distribution system. Since, GIS project scenarios imported to EPANET in (.inp) format in order to carry out simulation and find various WDS‟s parameters state.

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CHAPTER 2

STUDY AREA 2.1 LOCATION The study area, Vanasthalipuram is a part of Hyderabad city which is situated on southern part of India is a part of Hyderabad city. Vanasthalipuram zone occurs in the south-east zone of Hyderabad. It lies between latitudes 17°19‟49"N & 17°19'57"N and longitudes 78°34‟19"E & 78°30.43"E.

Figure 2.1 : Location of Hyderabad City in India (Source : http://www.luventicus.org)

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Figure 2.2: project study area in google map source(https://www.google.co.in/[email protected],78.5705656,17.29z)

2.2 TOPOGRAPHY The study area under consideration is on an average elevation of 542 m above the mean sea level. On the whole it has an undulating topography with the ground elevations generally vary between 537 m and 548 m.

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CHAPTER 3 POPULATION FORECASTING AND WATER QUANTITY ESTIMATION 3.1 Water Quantity Estimation The quantity of water required for municipal uses for which the water supply scheme has to be designed requires following data: 1. Water consumption rate (Per Capita Demand in litres per day per head) 2. Population to be served. Quantity= Per capita demand x Population 3.2 Water Consumption Rate It is very difficult to precisely assess the quantity of water demanded by the public, since there are many variable factors affecting water consumption. The various types of water demands, which a city may have, may be broken into following classes: Water Consumption for Various Purposes: Sl. no

Types of Consumption

Normal Range (lit/capita/day)

Average

%

1

Domestic consumption Industrial and Commercial Demand Public Uses Including Fire Demand

65-300

160

35

45-450

135

30

20-90

40

10

62

25

2

3

4

Losses and 45-150 Waste 3.2.1 Fire Fighting Demand:

It is usual to provide for fire fighting demand as a coincident draft on the distribution system along with the normal supply to the consumers as assumed. A provision in kiloliters per day SITS-CIVIL

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based on the formula of 100√p where, p = population in thousands may be adopted for communities larger than 50,000. It is desirable that one third of the fire fighting requirements from part of the service storage. The balance requirement may be distributed in several static tanks at strategic points. These tanks may be filled from the nearby ponds, streams or canals by water tankers wherever feasible. The high rise buildings should be provided with adequate fire storage from the protected water supply distribution 3.2.2 Factors affecting per capita demand: 1) Size of the city: Per capita demand for big cities is generally large as compared to that for smaller towns as big cities have sewered houses. 2) Presence of industries. 3) Climatic conditions. 4) Habits of people and their economic status. 5) Quality of water: If water is aesthetically & medically safe, the consumption will increase as people will not resort to private wells, etc. 6) Pressure in the distribution system. 7) Efficiency of water works administration: Leaks in water mains and services; and unauthorised use of water can be kept to a minimum by surveys. 8) Cost of water. 9) Policy of metering and charging method: Water tax is charged in two different ways: on the basis of meter reading and on the basis of certain fixed monthly rate. 3.3 Design Periods & Population Forecast This quantity should be worked out with due provision for the estimated requirements of the future. The future period for which a provision is made in the water supply scheme is known as the design period. Design period is estimated based on the following: 1) Useful life of the component, considering obsolescence, wear, tear, etc. 2) Expandability aspect. 3) Anticipated rate of growth of population, including industrial, commercial developments & migration-immigration. SITS-CIVIL

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4) Available resources. 5) Performance of the system during initial period. 3.3.1 Population Forecasting Methods The various methods adopted for estimating future populations are given below. The particular method to be adopted for a particular case or for a particular city depends largely on the factors discussed in the methods, and the selection is left to the discrection and intelligence of the designer. i) ii) iii) iv) v) vi) vii) viii)

Arithmetic Increase Method Geometric Increase Method Incremental Increase Method Decreasing Rate of Growth Method Simple Graphical Method Comparative Graphical Method Ratio Method Logistic Curve Method This quantity should be worked out with due provision for

1. Arithmetical increase method: This method is based on the assumptions that the increase in population is constant. the average increase per decade is calculated from the past records and in added to the present population to get the population in next decade. this method gives a low valves, as such is applied for old and large cities. The population at the end of „n‟ years or decade is calculated by the equation.

= P + ni Where, P n = population at the end of n years or decades. P

= present population.

I

= Average increase per year or decade

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2. Geometrical increase method: This is based on the assumption that the percentage increase in population is constant from decade to decade. Thus the population at the end of n years or decades is given as.

Pn= Where, r = Average percentage increase per year or decade This method gives high values and is applied to young and rapidly growing cities. 3. Incremental increase method: In this method the average increase is found as per arithmetical method and to that is added the average of the net incremental increase once for each future year or decal graph is plotted between time and population from available data the curve is smoothly extended for getting future value. The extension of the curve should be done carefully and requires experience and judgment. 4. Graphical method: A graph is plot between time and population from available data and the curve is smoothly extended for getting future value, the extension of the curve should be done carefully and requires experience and judgment. While planning a public water system of a colony, the per capita requirement may be taken as a minimum of 135LPCD. Details of 135 LPCD (Domestic) are as below : SITS-CIVIL

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Table 3.1: details of liter per capita demand Bathing 55liters Washing cloths

20liters

Drinking

5liters

Cooking

5liters

Washing utensils

10liters

Washing house

10liters

Flushing W C

30liters

TOTAL

135liters

The above demands are the average consumption. It is subjected to the following variation. I. Seasonal (up to 150%) more in summer than in winter. II. Die- urinal up to 150% due to climate, location and nature of people. For design purpose peak hour is taken as 3.0 time the average hourly demand. 3.3.2 POPULATION CALCULATION: The colony in which we are designing the water supply. To get the total population of the colony. Total population = Area x population Density Area of colony

= 444982.10 sq. meter

= 44.498210 ha (1ha = 10,000) Population Density

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= 500 / ha

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Total population

= 44.498210 X 500 = 22249 capita

Therefore the total no. of people in the colony = 22,249 capita 3.4 DEMAND OF WATER: The water tank which is designed by us has to serve the purpose for the design period of 30 years. Average demand Lit /day = population x Average consume of water in lpcd Population

= 22249 capita

Average consume of water in lpcd = 190liters Average demand Lit /day

= 22249 x 190 = 4227310 l/day (l/day = 1/24x60x60 l/sec) = 48.92719907 l/

Total demand of water (or) Peak demand/base demand = avg demand x peak demand Peak demand

=3

Peak demand

= 48.92719907 x 3 = 146.7815972 l/sec

Therefore the total demand of water = 146.7815

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CHAPTER 4

DISTRIBUTION SYSTEM Distribution system is a network of pipelines that distribute water to the consumers. They are designed to adequately satisfy the water requirement for a combination of 1 Domestic 2 Commercial 3 Industrial 4 Firefighting purposes. A good distribution system should satisfy the followings: i)

ii) iii)

Adequate water pressure at the consumer's taps for a specific rate of flow (i.e., pressures should be great enough to adequately meet consumer needs). Pressures should be great enough to adequately meet firefighting needs. At the same time, pressures should not be excessive because development of the pressure head brings important cost consideration and as pressure increases leakages increases too.

Note: In tower buildings, it is often necessary to provide booster pumps to elevate the water to upper floors. iv) v) vi)

vii)

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Purity of distributed water should be maintained. This requires distribution system to be completely water-tight. Maintenance of the distribution system should be easy and economical. Water should remain available during breakdown periods of pipeline. System of distribution should not such that if one pipe bursts, it puts a large area without water. If a particular pipe length is under repair and has been shut down, the water to the population living in the down-stream side of this pipeline should be available from other pipeline. During repairs, it should not cause any obstruction to traffic. In other words, the pipelines should not be laid under highways, carriage ways but below foot paths.

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4.1 Water Distribution Systems The purpose of distribution system is to deliver water to consumer with appropriate quality, quantity and pressure. Distribution system is used to describe collectively the facilities used to supply water from its source to the point of usage. 4.1.2 Requirements of Good Distribution System 1) Water quality should not get deteriorated in the distribution pipes. 2) It should be capable of supplying water at all the intended places with sufficient pressure head. 3) It should be capable of supplying the requisite amount of water during firefighting. 4) The layout should be such that no consumer would be without water supply, during the repair of any section of the system. 5) All the distribution pipes should be preferably laid one metre away or above the sewer lines. 6) It should be fairly water-tight as to keep losses due to leakage to the minimum. 4.2 Layouts of Distribution Network The distribution pipes are generally laid below the road pavements, and as such their layouts generally follow the layouts of roads. There are, in general, four different types of pipe networks; any one of which either singly or in combinations, can be used for a particular place. They are: i) ii) iii) iv)

I.

Dead End System Grid Iron System Ring System Radial System DEAD END OR TREE SYSTEM:

This system comprise of a supply main starting from the service reservoir along the main road. The sub-mains are connected to the main in the directions along roads, joining main road. The services connections are taken from these branches and minor distribution to the individual houses. This system is suitable for towns and cities with irregular and unplanned development.

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Figure 4.1: Dead end or tree system (source:http://nptel.ac.in/courses/105104102/images/dead%20end.jpg)

Branching Pattern with Dead End Reservoir

Sub-main

Sub- main Branches

Main (trunk)

1) Similar to the branching of a tree. 2) It consists of i) Main (trunk) line ii) Sub-mains iii) Branches Main line is the main source of water supply. There is no water distribution to consumers from trunk line. Sub-mains are connected to the main line and they are along the main roads. SITS-CIVIL

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Branches are connected to the sub-mains and they are along the streets. Lastly service connections are given to the consumers from branches. Advantages: i)

It is a very simple method of water distribution. Calculations are easy and simple to do. ii) The required dimensions of the pipes are economical. iii) This method requires comparatively less number of cut-off valves. iv) However, it is not usually favoured in modern water works practice for the following disadvantages. Disadvantages: i) ii)

iii) iv)

v)

The area receiving water from a pipe under repair is without water until the work is completed. In this system, there are large number of dead ends where water does not circulate but remains static. Sediments accumulate due to stagnation of the dead end and bacterial growth may occur at these points. To overcome this problem drain valves are provided at dead ends and stagnant water is drained out by periodically opening these valves but a large amount of water is wasted. It is difficult to maintain chlorine residual at the dead ends of the pipe. Water available for fire-fighting will be limited since it is being supplied by only one water main. The pressure at the end of the line may become undesirably low as additional areas are connected to the water supply system. This problem is common in many less-developed countries.

ii. GRID IRON SYSTEM: This system also known as “Interlaced” or “Reticulation” system and is improvement over the dead end system. In this system, the mains, sub mains and branches are interred connected with each other as shown in below figure. The water circulates freely throughout the system. This system is suitable for well planned towns and cities with a regular grid of main roads and cross roads.

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Figure 4.2: Grid iron system (source: http://nptel.ac.in/courses/105104102/images/Grid%20iron.jpg)

Grid Pattern Reservoir Main line

In grid pattern, all the pipes are interconnected with no dead-ends. In such a system, water can reach any point from more than one direction. Advantages: i)

ii)

iii)

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Since water in the supply system is free to flow in more than one direction, stagnation does not occur as readily as in the branching pattern. In case of repair or break down in a pipe, the area connected to that pipe will continue to receive water, as water will flow to that area from the other side. Water reaches all points with minimum head loss.

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iv)

At the time of fires, by manipulating the cut-off valves, plenty of water supply may be diverted and concentrated for fire-fighting.

Disadvantages: i)

Cost of pipe laying is more because relatively more length of pipes is required. More number of valves are required. The calculation of pipe sizes are more complicated.

ii) iii)

Grid Pattern with Loops Loops are provided in a grid pattern to improve water pressure in portions of a city (industrial, business and commercial areas). Loops should be strategically located so that as the city develops the water pressure should be sustained. The advantages and disadvantages of this pattern are the same as those of the grid pattern DESIGN CONSIDERATIONS Diameter ≥ 80 mm.

i)

For pipes with fire hydrants ≥ 100 mm. ii)

Velocity > 0.6 m/sec. Common range is 1.0 - 1.5 m/sec.

iii) iv)

If velocity < 0.6 m/sec (due to minimum diameter limit) then drain valve is used on that pipe. Minimum pressure at the top of the highest floor of a building is about 5m.

iii. CIRCULAR OR RING SYSTEM: In this system, the entire locality is divided into either rectangular or circular blocks. The water mains are laid along the peripheral roads with sub mains branching out from the mains and running on the inner roads. Thus, every point can receive the supply from two directions. This system is best suited for well plan towns and obvious, the most ideal system. The layout is shown in above figure.

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Figure 4.3: Ring system source(https://vertassets.blob.core.windows.net/image/b342017d/b342017d-8353-4ffd8009-b3d347cee57d/ringsystem.jpg )

ADVANTAGES: i) ii) iii) iv)

During breakdown or repairs water can be drawn from other lines. For fore fighting, large quantities of water can be drawn from all directions. Design calculations are easy. This system possesses the advantages of both dead end system and grid iron system.

DISADVANTAGES: i) ii) iii)

Large numbers of valves are required. A pipe length requirement is also more. Overall cost is high.

iv. RADIAL SYSTEM: This system is the reverse or ring system i.e. water radially from one point to the outer periphery. The entire city is divided into number of zones and distribution reservoir is placed in the center of each zone. The water supply lines are laid radically from it as in figure. This suitable where the roads are laid radially in the city.

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Figure 4.4: Radial system (source:https://vertassets.blob.core.windows.net/image/86a35446/86a35446-a123-4656-8a48226905fdfe17/radialsystem.jpg)

ADVANTAGES: i) ii) iii)

Advantageously used for “Direct-Indirect” system. Ensures high pressure and efficient water distribution. Design calculations are easy.

DISADVANTAGES: i) ii) iii)

Suitable for town only with radial layout of roads and cannot be adopted for other patterns. Numbers of elevated reservoirs are more. Overall cost is more.

The suitability of any one of the above methods depends on the layouts of roads, as the pipelines are generally run below the street pavements. 4.3 System of distributions: Depending upon the method of distribution, how the required pressure is maintained in the distribution system, it is classified in to three types. 1) Gravity system 2) Direct pumping system 3) Combine system or dual system One of the above systems is selected for distribution based on. SITS-CIVIL

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i) ii) iii)

The level of source of water and that of the city. Topography of the area. Other local conditions and considerations.

GRAVITY SYSTEM: In this system, water is distributed by the gravity only, to the consumer‟s points. It is suitable for situation where the source of water is located at a sufficiently higher level than town. Such a situation can be advantageously utilized to develop the required pressure in the distribution system by gravity. This system is economical and reliable but not suitable for storage. DIRECT PUMPING SYSTEM: In this system, the treated water is directly pumped into distribution of pipe by means of height lift pumps without a storing anywhere. The disadvantages of this system are, 1) Continues skilled supervision is required to operate the pumps at variable speed. 2) In case of failure or repairs to pumps supply of water cannot be made. 3) The only advantage is that during fire accident‟s large quantities of water at high pressure can be pumped to put off the fire. COMBINED OR DUAL SYSTEM: This is also called “pumping with storage system” and “direct – indirect system”. In this system the storage the portable water is pumped at constant rate into an elevated reservoir as well as directly into the distribution system. During the minimum demand pumping rate is more than the demand. This excess water is pumped into the storage elevated reservoir and used during maximum demand by gravity system and direct pumping system. This is most widely adopted system in water supply scheme for its obvious advantages such as. 1) Pumps can be operated with uniform speed at their rated capacities. 2) It is reliable system as there is always some reservoir water in elevated tanks to supply during peak demand, power failure and break down. 3) In case fire accidents large quantity of water can be draw directly from the elevated reservoir and also by pumping. 4) It is an economic and efficient system. SITS-CIVIL

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4.3.1 System Configurations Branching vs. grid systems: 1) A grid system is usually preferred over a branching system, since it can furnish a supply to any point from at least two directions 2) The branching system has dead ends, therefore, does not permit supply from more than one direction. Should be avoided where possible. 3) In locations where sharp changes in topography occur (hilly or mountainous areas), it is common practice to divide the distribution system into two or more service areas. 4.3.2 Basic System Requirements Pressure: i) ii)

Pressure should be great enough to adequately meet consumer and fire-fighting needs. Pressure should not be excessive: a) Cost consideration b) Leakage and maintenance increase

Capacity: i)

The capacity is determined on the bases of local water needs plus fire-fighting demand. ii) Pipe sizes should be selected to avoid high velocities: a) Pipe sizes should selected based on flow velocity of 3-5 fps b) Where fire-fighting is required, minimum pipe diameter is 6 in. 4.3.3 Hydraulic Design The design flowrate is based on the maximum of the following two rates: i) ii)

Maximum day demand plus fire deman. Maximum hourly rate

Analysis of distribution system: i)

Distribution system have series of pipes of different diameters. In

ii)

order to simplify the analysis, skeletonizing is used . Skeletonizing is the replacement of a series of pipes of varying diameters with one equivalent pipe or replacing a system of pipes with one equivalent

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4.4 Distribution Reservoirs Distribution reservoirs, also called service reservoirs, are the storage reservoirs, which store the treated water for supplying water during emergencies (such as during fires, repairs, etc.) and also to help in absorbing the hourly fluctuations in the normal water demand. 4.4.1 Functions of Distribution Reservoirs: • • •

to absorb the hourly variations in demand. to maintain constant pressure in the distribution mains. water stored can be supplied during emergencies.

4.4.2 Location and Height of Distribution Reservoirs: • •

should be located as close as possible to the center of demand. water level in the reservoir must be at a sufficient elevation to permit gravity flow at an adequate pressure.

4.4.3 Types of Reservoirs 1. 2. 3. 4.

Underground reservoirs. Small ground level reservoirs. Large ground level reservoirs. Overhead tanks.

Design of Reservoirs: When a barrier is constructed across some river in the form of dam, water gets stored on the upstream side of the barrier, forming a pool of water, generally called a River Reservoir. The quality of water stored in such a reservoirs is not much different from that of a natural lake. The water so stored in a given reservoirs during rainy season can be easily used almost throughout the year, till time of arrival of the next rainy season, to refill the emptying reservoirs again.

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4.4.4 Storage Capacity of Distribution Reservoirs The total storage capacity of a distribution reservoir is the summation of: 1.

2.

3.

Balancing Storage: The quantity of water required to be stored in the reservoir for equalising or balancing fluctuating demand against constant supply is known as the balancing storage (or equalising or operating storage). The balance storage can be worked out by mass curve method. Breakdown Storage: The breakdown storage or often called emergency storage is the storage preserved in order to tide over the emergencies posed by the failure of pumps, electricity, or any other mechanism driving the pumps. A value of about 25% of the total storage capacity of reservoirs, or 1.5 to 2 times of the average hourly supply, may be considered as enough provision for accounting this storage. Fire Storage: The third component of the total reservoir storage is the fire storage. This provision takes care of the requirements of water for extinguishing fires. A provision of 1 to 4 per person per day is sufficient to meet the requirement.

The total reservoir storage can finally be worked out by adding all the three storages. Figure 4.4.1:Surface reservoir

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Surface Reservoir

Figure 4.4.2:Elevated reservoir

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Elevated tanks

2

Distribution Reservoirs Location i) ii) iii) iv)

Distribution reservoirs should be located strategically for maximum benefits. Normally the reservoir should be near the center of use. For large areas, a number of reservoirs may be located at key locations A central location decreases the friction losses by reducing the distance to the serviced area.

Storage function i) ii)

iii)

To provide head required head. To provide excess demand such as: a) fire-fighting: should be sufficient to provide flow for 10-12 hours. b) emergency demands: to sustain the demand during failure of the supply system and times of maintenance. To provide equalization storage.

Depending upon the purpose served by a given reservoirs, the reservoirs may be broadly divided into the following three types. 1) Storage reservoirs. SITS-CIVIL

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2) Flood control reservoirs. 3) Multipurpose reservoirs. 4) Distributions reservoirs.

Figure 4.4.3: construction of ground level elevated level storage reservoirs

Reservoirs is a simple storage tank constructed within a city water supply system, and is called a Distribution Reservoirs; and such reservoirs is evidently not a river reservoirs, but is a simple storage tank. A distribution reservoir is a small storage reservoirs constructed within a city water supply system. such reservoirs can be filled by pumping water at a certain rate and can be to supply water even at rate higher than the inflow rate during periods of maximum demands (called critical periods of demand). such reservoirs are, therefore, helpful in permitting the pumps or the water treatment plants to work at a uniform rate, and they store water SITS-CIVIL

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during the hours of no demand or less demand, and supply water from their storage during the critical periods of maximum demand. Figure 4.4.4: construction of ground level storage reservoir

4.4.5 Selection of site for Distribution Reservoir system: i) ii) iii) iv) v) vi)

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Provide maximum benefits of head and pressure (elevation high enough to develop adequate pressures in system) Near center of use (decreases friction losses and therefore loss of head by reducing distances to use) Great enough elevation to develop adequate pressures in system. May require more than one in large metropolitan area.32 Area of the Reservoir should be far away from the earth-quake epicenter. Reservoir bed should be impermeable and should not allow quick percolation of stored water. Page 28

vii)

The reservoir basin should be wide above the dam site to facilitate more storage of water. viii) Reservoir site must have adequate capacity. ix) The reservoir occupation should not submerge valuable land and other properties.

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CHAPTER 5

GEO GRAPHICAL INFORMATION SYSTEM 5.1 Introduction A geographic information system (GIS) is a computerbased tool for mapping and analysing spatial data. GIS technology integrates common database operations such as query and statistical analysis with the unique visualization and geographic analysis benefits offered by maps. These abilities distinguish GIS from other information systems and make it valuable to a wide range of public and private enterprises for explaining events, predicting outcomes, and planning strategies. GIS is considered to be one of the most important new technologies, with the potential to revolutionize many aspects of society through increased ability to make decisions and solve problems.

Figure 5.1:GIS data

The major challenges that we face in the world today -overpopulation, pollution, deforestation, natural disasters – all have a SITS-CIVIL

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critical geographic dimension. Local problems also have a geographic component that can be visualized using GIS technology, whether finding the best soil for growing crops, determining the home range for an endangered species, or discovering the best way to dispose of hazardous waste. Careful analysis of spatial data using GIS can give insight into these problems and suggest ways in which they can be addressed. Map making and geographic analysis are not new, but a GIS performs these tasks better and faster than do the old manual methods. And, before GIS technology, only a few people had the skills necessary to use geographic information to help with decision making and problem solving. Today, GIS is a multi-billion-dollar industry employing hundreds of thousands of people worldwide. GIS is taught in high schools, colleges, and universities throughout the world. Professionals in every field are increasingly aware of the advantages of thinking and working geographically. 5.2 Components of Geographic Information System A working Geographic Information System seamlessly integrates five key components: hardware, software, data, people, and methods.

GIS components (Source:http://planet.botany.uwc.ac.za/nisl/GIS/GIS_primer/images/pic061.gif)

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5.2.1 Hardware Hardware includes the computer on which a GIS operates, the monitor on which results are displayed, and a printer for making hard copies of the results. Today, GIS software runs on a wide range of hardware types, from centralized computer servers to desktop computers used in stand-alone or networked configurations. The data files used in GIS are relatively large, so the computer must have a fast processing speed and a large hard drive capable of saving many files. Because a GIS outputs visual results, a large, high-resolution monitor and a high-quality printer are recommended. 5.2.2 Software GIS software provides the functions and tools needed to store, analyse, and display geographic information. Key software components include tools for the input and manipulation of geographic information, a database management system (DBMS), tools that support geographic query, analysis, and visualization, and a graphical user interface (GUI) for easy access to tools. The industry leader is ARC/INFO, produced by Environmental Systems Research, Inc. The same company produces a more accessible product, ArcView, that is similar to ARCINFO in many ways. 5.2.3 Data Possibly the most important component of a GIS is the data. A GIS will integrate spatial data with other data resources and can even use a database management system, used by most organizations to organize and maintain their data, to manage spatial data. There are three ways to obtain the data to be used in a GIS. Geographic data and related tabular data can be collected in-house or produced by digitizing images from aerial photographs or published maps. Data can also be purchased from commercial data provider. Finally, data can be obtained from the federal government at no cost. 5.2.4 People GIS users range from technical specialists who design and maintain the system to those who use it to help them perform their everyday work. The basic techniques of GIS are simple enough to master that even students in elementary schools are learning to use GIS.

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Because the technology is used in so many ways, experienced GIS users have a tremendous advantage in today‟s job market. 5.2.5 Methods A successful GIS operates according to a well-designed plan and business rules, which are the models and operating practices unique to each organization. 5.3 How a GIS work A GIS stores information about the world as a collection of thematic layers that can be linked together by geography. This simple but extremely powerful and versatile concept has proven invaluable for solving many real-world problems from modelling global atmospheric circulation, to predicting rural land use, and monitoring changes in rainforest ecosystems. 5.3.1 Geo Graphic references Geographic information contains either an explicit geographic reference such as a latitude and longitude or national grid coordinate, or an implicit reference such as an address, postal code, census tract name, forest stand identifier, or road name. An automated process called geocoding is used to create explicit geographic references (multiple locations) from implicit references (descriptions such as addresses). These geographic references can then be used to locate features, such as a business or forest stand, and events, such as an earthquake, on the Earth's surface for analysis. Vector and Raster Models:

Figure 5.3.1:vector and rastar models (source:http://docs.irenees.net/ppgis/Picture1_b.png) SITS-CIVIL

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Geographic information systems work with two fundamentally different types of geographic models--the "vector model" and the "raster model." In the vector model, information about points, lines, and polygons is encoded and stored as a collection of x, y coordinates. The location of a point feature, such as a bore hole, can be described by a single x,y coordinate. Linear features, such as roads and rivers, can be stored as a collection of point coordinates. Polygonal features, such as sales territories and river catchments, can be stored as a closed loop of coordinates. The vector model is extremely useful for describing discrete features, but less useful for describing continuously varying features such as soil type or accessibility costs for hospitals. The raster model has evolved to model such continuous features. A raster image comprises a collection of grid cells rather like a scanned map or picture. Both the vector and raster models for storing geographic data have unique advantages and disadvantages. Modern GISs are able to handle both models. 5.3.2 GIS Tasks General purpose GIS‟s perform seven tasks. 1) 2) 3) 4) 5) 6)

Input of data Map making Manipulation of data File management Query and analysis Visualization of results

5.3.2.1 Input of Data Before geographic data can be used in a GIS, the data must be converted into a suitable digital format. The process of converting data from paper maps or aerial photographs into computer files is called digitizing. Modern GIS technology can automate this process fully for large projects using scanning technology; smaller jobs may require some manual digitizing which requires the use of a digitizing table. 39 Today many types of geographic data already exist in GIScompatible formats. These data can be loaded directly into a GIS. 5.3.2.2 Map Making SITS-CIVIL

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Maps have a special place in GIS. The process of making maps with GIS is much more flexible than are traditional manual or automated cartography approaches. It begins with database creation. Existing paper maps can be digitized and computer-compatible information can be translated into the GIS. The GIS-based cartographic database can be both continuous and scale free. Map products can then be created centered on any location, at any scale, and showing selected information symbolized effectively to highlight specific characteristics. The characteristics of atlases and map series can be encoded in computer programs and compared with the database at final production time. Digital products for use in other GIS‟s can also be derived by simply copying data from the database. In a large organization, topographic databases can be used as reference frameworks by other departments. 5.3.2.3 Manipulation of Data It is likely that data types required for a particular GIS project will need to be transformed or manipulated in some way to make them compatible with your system. For example, geographic information is 40 available at different scales (street center line files might be available at a scale of 1:100,000; census boundaries at 1:50,000; and postal codes at 1:10,000). Before this information can be integrated, it must be transformed to the same scale. This could be a temporary transformation for display purposes or a permanent one required for analysis. GIS technology offers many tools for manipulating spatial data and for weeding out unnecessary data. 5.3.2.4 File Management For small GIS projects it may be sufficient to store geographic information as simple files. There comes a point, however, when data volumes become large and the number of data users becomes more than a few, that it is best to use a database management system (DBMS) to help store, organize, and manage data. A DBMS is nothing more than computer software for managing a database--an integrated collection of data. There are many different designs of DBMS‟s, but in GIS the relational design has been the most useful. In the relational design, data are stored conceptually as a collection of tables. Common fields in different tables are used to link them together. This simple design has been widely used, SITS-CIVIL

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primarily because of its flexibility and very wide deployment in applications both within and without GIS. GIS provides both simple point-and-click query capabilities and sophisticated analysis tools to provide timely information to managers and analysts alike. GIS technology really comes into its own when used to analyse geographic data to look for patterns and trends, and to undertake "what if" scenarios. Modern GISs have many powerful analytical tools, but two are especially important. Proximity Analysis is used to examine spatial relationships by determining the proximate relationship between features. Overlay Analysis integrates different data layers to look for patterns and relationships. At its simplest, this could be a visual operation, but analytical operations require one or more data layers to be joined physically. For example, to analyse the impact of urbanization on ecological characteristics of an area, an overlay could integrate data on soils, hydrology, slope, vegetation, and land use. Queries could be used to identify sources of pollution, to delineate potentially sensitive areas, or to plan for increased population growth in the area.

Figure 5.3.2.4.1:Relationship between features (source:http://ibis.geog.ubc.ca/courses/geob370/lectures/Intro/gis.gif)

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5.3.2.5 Visualization For many types of geographic operations, the end result is best visualized as a map or graph. Maps are very efficient at storing and communicating geographic information. While cartographers have created maps for millennia, GIS provides new and exciting tools to extend the art and science of cartography. Map displays can be integrated with reports, three-dimensional views, photographic images, and with multimedia.

Figure 5.3.2.5.1:Visualization of image THE IMPORTANCE OF GEOGRAPHIC SYSTEMS

INFORMATION

The ability of GIS to search databases and perform geographic queries has revolutionized many areas of science and business. It can be invaluable during a decision-making process. The information can be presented succinctly and clearly in the form of a map and accompanying report, allowing decision makers to focus on the real issues rather than trying to understand the data. Because GIS products can be produced quickly, multiple scenarios can be evaluated efficiently and effectively. For this reason, in today‟s world, the ability to use GIS is increasingly important.

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5.4 GEOGRAPHIC INFORMATION DISTRIBUTION SYSTEMS

SYSTEMS

IN

WATER

Figure 5.4.1:gis software Many have characterized Geographic Information Systems (GIS) as one of the most powerful of all information technologies because it focuses on integrating knowledge from multiple sources and creates a 44 crosscutting environment for collaboration. GIS is a system for the management, analysis, and display of geographic knowledge, which is represented using a series of information sets. In the present study, GIS will be used to organize the data for usage in water distribution networks design, and analysis. In addition, GIS is used as a tool for number of created applications for network management; such as identifying valves to be closed in case of pipe break, service area for treatment plants, and network skeletonization. Finally, GIS is used to provide graphical display of results obtained from both hydraulic simulation, and optimization models; linking tabular data with geographic locations, and graphical drawing. 5.4.1 Building Geometric Networks Geometric networks offer a way to model common networks and infrastructures found in the real world. Water distribution, electrical lines, gas pipelines, telephone services, and water flow in a water pipe networks are all examples of resource flows that could be modelled and analysed using geometric network.

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In the present paper, geometric network is created from the set of feature class layers presented earlier, along with connectivity rules that are used to represent and model the behavior of a common network infrastructure in the real world. We define the roles that various features will play in the geometric network and rules for how resources flow through the geometric network. Geometric network consisted of two main elements: Edges and Junctions i)

ii) iii)

Junctions are the features that allow two or more edges to connect and facilitate the transfer of flow between edges. Junctions are created from point feature classes in a feature dataset and correspond to junction elements in the logical network. Examples of junctions are valves, hydrants, fittings, and meters. Edges are features, which have a length through which some commodity flows. Edges are created from line feature classes in a feature dataset and correspond to edge elements in a logical network. Examples of edges are water lines, hydrant line layer, and house connection layer.

There are two types of edges in a geometric network. The first is Simple edges, which are always connected to exactly two junctions, one at each end, and Complex edges are always connected to at least two junctions at their endpoints but can be connected to additional junctions along their length. Table 1 water distribution network model edge type. Edge layer Type of edge Water pipes feature class Complex edge Hydrants pipe feature class Simple edge Streets feature class Complex edge House connection feature class Simple The present paper sets water pipeline networks as complex edge feature to save the time required for hydraulic analysis, as single water pipe network is connected to many meters through house connections. That will be later simplified for hydraulic simulation to only two junctions at the start and end of each pipe; Accumulating the demand to either downstream junction, or splitting the demand in half between the two ends junctions using custom made applications presented by the current study.

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ARCGIS BASIC TOOLS In this section several basic GIS tools for data visualization and data inquiry are described

Figure 5.4.1.1:GIS tools SQL Attributes Select SQL is a standard computer language for accessing and managing databases. ArcGIS uses SQL to define a subset of data on which to perform some operation. Figure 5.4.1.2 select by attributes file loading

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Figure 5.4.1.3: loaded file with point, line and polygon features

The study area lies between latitudes 17°19'31"N & 17°19'57"N and longitudes 78°34'19"E & 78°34'30"E. The catchment covers a total area of about 44.498210 ha with an average elevation of 529.62 m above the mean sea level. The ground elevations are between 537 m and 548 m. This polygon feature class is used to clip the catchment feature class to generate the sub catchments feature class as shown in figure 5.4.1.1. Similarly, Drainage Lines, Longest Flow Path and Drainage Point feature classes are being clipped for the area of interest as shown in figures 5.4.1.2. and 5.4.1.3. Figure 5.4.1.4:line features

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Thematic Maps Thematic maps symbology are a helpful in the way to visualize data associated with drawings, they are used to represent data with colures and symbols, by default, all the parcels are drawn using the same symbol when you add them. Also, can be drawn based on an attribute such as; (e.g. Diameter in pipelines, and Type in junctions). Thematic maps facilitate the data recognition and identification using symbols and colors as shown in figure. Figure 5.4.1.5:symbolizing of features

Figure 4 Thematic map symbology for WDN Labeling Labeling is a feature inside ArcGIS used to annotate the data stored in a feature and visualize the data into a written form that can be easily seen on printed map or on screen.

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Figure 5.4.1.6:labelling

5.4.2 ARCGIS applications for water distribution system mangement In this section, some created custom applications for water distribution networks management are explained. The created applications in the present study cover the fields of; identifying isolating valves in case of pipeline break, adjusting GIS layers to equivalent hydraulic analysis layers, service area allocator for water distribution plants, and demand aggregation for junctions in skeletonized networks. 5.4.2.1 Custom Valve Isolation Application The application performs a valve isolation trace based on selected pipes and display results. By using the features of geometric network; a network analysis, based on the upstream and downstream connectivity for the water pipeline feature to identify the valves that isolate selected pipe. Then, all valves are highlighted and summary report for data is being exported in suitable format. The application is used in the preliminary stage of design to ensure that every region for pipeline network could be easily isolated in case of pipeline break without affecting other regions. Also, used in post optimization, post design stage to identify the key valves that control the network and to ensure proper isolation in case of pipeline breakage.

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Figure 5.4.2.1.1:custom valve application

Figure 5.4.2.1.2:creating pipe lines

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5.4.2.2 Transfer Attributes Application This application is intended for use in case of adjusting GIS layers to be used in hydraulic analysis models (e.g., ELGTnet, or EPAnet). It copies attribute data from point features (e.g., pumps) to adjacent line layer (e.g., Water line layer). As it worth mentioning that in hydraulic analysis procedures pumps and valves (e.g., PRV, FCV PSV …etc) are modeled as pipe with zero length the model is used to transfer pump & valves nodal data in GIS environment into adjacent Lines(edges) to be ready for ELGTnet model, and EPANET model. Figures (8, 9) explain the difference between GIS network representation, and hydraulic analysis modells representation.

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CHAPTER 6

EPANET 6.1 Introduction EPANET is software that models water distribution piping systems. EPANET is public domain software that may be freely copied and distributed. It is a Windows 95/98/NT/XP program. EPANET performs extended period simulation of the water movement and quality behavior within pressurized pipe networks. Pipe networks consist of pipes, nodes (junctions), pumps, valves, and storage tanks or reservoirs. EPANET tracks: the flow of water in each pipe, i) ii) iii) iv) v) vi)

the pressure at each node the height of the water in each tank, the type of chemical concentration throughout the network during a simulation period, water age, source, and tracing.

Capabilities EPANET's Windows user interface provides a visual network editor that simplifies the process of building piping network models and editing their properties and data. EPANET provides an integrated computer environment for editing input data. Various data reporting and visualization tools are used to assist in interpreting the results of a network analysis. These include i) ii) iii) iv) v) vi) vii) viii)

color-coded network maps, data tables, energy usage, reaction, calibration, time series graphs, profile plots, contour plots. EPANET provides a fully equipped, extended-period hydraulic analysis package that can: 1) Simulate systems of any size SITS-CIVIL

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2) Compute friction head loss using the Hazen-Williams, the Darcy Weisbach, or the Chezy-Manning formula 3) Include minor head losses for bends, fittings, etc. 4) Model constant or variable speed pumps 5) Compute pumping energy and cost 6) Model various types of valves, including shutoff, check, pressure regulating, and flow control 7) Account for any shape storage tanks (i.e., surface area can vary with height) 8) Consider multiple demand categories at nodes, each with its own pattern of time variation 9) Model pressure-dependent flow issuing from sprinkler heads 10)Base system operation on simple tank level, timer controls or complex rule-based controls In addition, EPANET's water quality analyser can: 1) Model the movement of a non-reactive tracer material through the network over time. 2) Model the movement and fate of a reactive material as it grows (e.g., a disinfection by-product) or decays (e.g., chlorine residual) over time. 3) Model the age of water throughout a network. 4) Track the percent of flow from a given node reaching all other nodes over time. 5) Model reactions both in the bulk flow and at the pipe wall. 6) Allow growth or decay reactions to proceed up to a limiting concentration. 7) Employ global reaction rate coefficients that can be modified on a pipe-by-pipe basis. 8) Allow for time-varying concentration or mass inputs at any location in the network. 9) Model storage tanks as being complete mix, plug flow, or twocompartment reactors. Applications EPANET helps water utilities maintain and improve the quality of water delivered to consumers. It can be used to: i) ii) SITS-CIVIL

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iii) iv)

conduct consumer exposure assessments, evaluate alternative strategies for improving water quality, such as altering source use within multi-source system v) modify pumping and tank filling/emptying schedules to reduce water age, vi) use booster disinfection stations at key locations to maintain target residuals, and vii) plan and improve a system's hydraulic performance, viii) assist with pipe, pump, and valve placement and sizing, ix) energy minimization, x) fire flow analysis, xi) vulnerability studies, and xii) operator training. Water Distribution Networks (WDNs) serve many purposes in addition to the provision of water for human consumption, which often accounts for less than 2% of the total volume supplied. Piped water is used for washing, sanitation, irrigation and firefighting. Networks are designed to meet peak demands; in parts of the network this creates low-flow conditions that can contribute to the deterioration of microbial and chemical water quality. The purpose of a system of pipes is to supply water at adequate pressure and flow. However, pressure is lost by the action of friction at the pipe wall. The pressure loss is also dependent on the water demand, pipe length, gradient and diameter. Several established empirical equations describe the pressure–flow relationship (Webber, 1971) and these have been incorporated into network modelling software packages to facilitate their solution and use. There is still not a convenient evaluation for the reliability of water distribution systems. Traditionally, a water distribution network design is based on the proposed street plan and the topography. Using commercial software, the modeller simulates flows and pressures in water distribution networks play an important role in modern societies being its proper operation directly related to the population‟s well-being. However, water supply activities tend to be natural monopolies, so to guarantee good service levels in a sustainable way the water supply systems performance must be evaluated. The incorporation of performance assessment methodologies in the management practices creates competitiveness mechanisms that lead to the culture of efficiency and the pursuit of continuous improvement.

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The primary task for water utilities is to deliver water of the required quantity to individual customers under sufficient pressure through a distribution network. The distribution of drinking water in distribution networks is technical challenge both in quantitative and qualitative terms. It is essential that each point of the distribution network be supplied without an invariable flow of water complying with all the qualitative and quantitative parameters. The water supply in most Indian cities is only available for a few hours per day, pressure is irregular, and the water is of questionable quality. Intermittent water supply, insufficient pressure and unpredictable service impose both financial and health costs on Indian households. Leakage hotspots are assumed to exist at the model nodes identified. For this study area vanasthalipuram zone of Hyderabad city City has been identified and the network model for the area under consideration will be prepared and studied for water losses. 6.2 Objective To analyse the existing water distribution system using EPANET and to suggest some measures if present network does not fulfil the present and future demand. 6.3 Study area Vanasthalipuram zone is a part of Hyderabad city. Vanasthalipuram zone occurs in the south-east zone of Hyderabad. Vanasthalipuram zone covers the following colony‟s under the water distribution system:  Hasthinapuram colony Phase I, Phase II  Huda sai nagar colony  Raitu bazar  Sachivalaya nagar

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Figure 5.3.1 selected area

6.4 EPANET software EPANET is a computer program that performs extended period simulation of hydraulic and water quality behaviour within pressurized pipe networks. A network consists of pipes, nodes (pipe junctions), pumps, valves and storage tanks or reservoirs. EPANET tracks the flow of water in each pipe, the pressure at each node, the height of water in each tank, and the concentration of a chemical species throughout the network during a simulation period comprised of multiple time steps. In addition to chemical species, water age and source tracing can also be simulated. EPANET was developed by the water supply and water resources division (formerly the drinking water research division) of the U.S Environmental protection agency's national risk management research laboratory. It is public domain software that may be freely copied and distributed. EPANET is designed to be a research tool for improving our understanding of the movement and fate of drinking water constituents within distribution systems. It can be used for many different kinds of applications in distribution systems analysis. Sampling program design, hydraulic model calibration, chlorine residual analysis, and consumer exposure assessment are some examples. EPANET can help assess SITS-CIVIL

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alternative management strategies for improving water quality throughout a system. Figure 5.4.1: EPANET software window

Running under windows, EPANET provides an integrated environment for editing network input data, running hydraulic and water quality simulations, and viewing the results in a variety of formats. These include color-coded network maps, data tables, time series graphs, and contour plots. 6.5 HYDRAULIC MODELLING CAPABILITIES Full-featured and accurate hydraulic modelling is a prerequisite for doing effective water quality modelling. EPANET contains a state-of-the-art hydraulic analysis engine that includes the following capabilities: 1. places no limit on the size of the network that can be analysed 2. computes friction head loss using the Hazen-William, DarcyWeisbach or Chezy Manning formula 3. Includes minor head losses for bends, fittings, etc. 4. models constant or variable speed pumps 5. computes pumping energy and cost 6. modells various types of valves including shutoff, check, pressure regulating, and flow control valves 7. allows storage tanks to have any shape (i.e., diameter can vary with height) SITS-CIVIL

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8. considers multiple demand categories at nodes, each with its own pattern of time variation 9. models pressure-dependent flow issuing from emitters (sprinkler heads) 10.Can perform system operation on both simple tank level and timer controls and on complex rule-based controls. EPANET's Windows user interface provides a network editor that simplifies the process of building piping network models and editing their properties. Various data reporting and visualization tools such as graphical views, tabular views, and special reports, and calibration are used to assist in interpreting the results of a network analysis (EPA, 2000). By employing these features, EPANET can study water quality phenomena as:  blending water from different sources  Age of water throughout a system  Loss of chlorine residuals.  Growth of disinfection by-products.  Tracking contaminant propagation events. 6.6 Model Input Data In order to analyse the WDN using EPANET following input data files are needed: 1. Junction Report Junctions are points in the network where links join together and where water enters or leaves the network. The basic input data required for junctions are: 1. Elevation above some reference (usually mean sea level) 2. Water demand (rate of withdrawal from the network) 3. Initial water quality. The output results computed for junctions at all time periods of a simulation are: 1. Hydraulic head (internal energy per unit weight of fluid) 2. Pressure 3. Water quality. SITS-CIVIL

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Junctions can also: 1. Have their demand vary with time 2. Have multiple categories of demands assigned to them 3. have negative demands indicating that water is entering the network 4. be water quality sources where constituents enter the network 5. Contain emitters (or sprinklers) which make the outflow rate depend on the pressure.

Figure 5.6.1:Junction report

2. Pipe Report Pipes are links that convey water from one point in the network to another. EPANET assumes that all pipes are full at all times. Flow direction is from the end at higher hydraulic head (internal energy per weight of water) to that at lower head. The principal hydraulic input parameters for pip es are: 1. start and end nodes 2. diameter 3. length 4. roughness coefficient (for determining headloss) 5. Status (open, closed, or contains a check valve). Computed outputs for pipes include: 1. flow rate SITS-CIVIL

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2. velocity 3. headloss 4. Darcy-Weisbach friction factor 5. average reaction rate (over the pipe length) 6. Average water quality (over the pipe length). The hydraulic head lost by water flowing in a pipe due to friction with the pipe walls can be computed using one of three different formulas: 1. Hazen-Williams formula 2. Darcy-Weisbach formula 3. Chezy-Manning formula The Hazen-Williams formula is the most commonly used headloss formula in the US. It cannot be used for liquids other than water and was originally developed for turbulent flow only. The Darcy-Weisbach formula is the most theoretically correct. It applies over all flow regimes and to all liquids. The Chezy-Manning formula is more commonly used for open channel flow. Figure 5.6.2:pipe report

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5.6.3 reservoir report

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CHAPTER 7

Analysis and Results The study area lies between latitudes 17°19‟49"N & 17°19'57"N and longitudes 78°34'19"E & 78°34'30"E. The catchment covers a total area of about 44.498210 ha with an average elevation of 542 m above the mean sea level. The ground elevations are between 537 m and 548 m where in Northern area having a maximum elevation. Table 7.1:elevations and base demands of junctions

Table 7.2 pipes report

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Figure 7.3 graph of distribution of elevation

Figure 7.4 graph of distribution of base demand

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Figure 7.5 distribution of length

Figure 7.6 distribution of flow

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Figure 7.7 : Run was successful

Figure 7.8: clear water flow

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Head loss in pipes: Here we cross checked head loss in 195 pipes, by HAZENWILLIAMS formula method. Data:Diameter of pipe (D)

= 0.1m

Length of the pipe (L)

= 130m

=

Area of the pipe (A) Discharge of pipes

(Q)

Hydraulic radius

(r)

= 0.007854

= 0.48

=

= 0.025 m

Hazen – Williams coefficient (C) = 130 Slope of hydraulic grade line (S) = ? We know that V = 0.849 C

Q=AV V=

=

S=(

= 61.1153 m/s )

=(

)

= 26.244 Total Head loss in the pipe (

=SXL = 26.244 x 130 = 3411.79 m

Similarly for all the pipes and nodes

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REFERENCES “Water supply system and evaluation methods” volume1: water supply concepts HARRYE.HICKEY,PH.D Chapter1 fundamental considerations “water distribution network” CE370 “What is geographical information system” “Geographical information system in water demand network” “geographical information system” “EPANET 2.0” Chapter 8 “Water distribution system” International journal of advanced computer science and application, vol.7, no.2 (IJACSA) “Design of hydraulically balanced water distribution network based on GIS and EPANET” by RASOOLI AHMADULLAH , KANG DONGSHIK International conference on ecological, environmental and biological sciences (ICEEBS 2012) JAN:7-8,2012 Dubai “Simulation of hydraulic parameters in water distribution network using EPANET and GIS “ by Dr.Ramesh, L.Santhosh and C.J.Jagadeesh Mannual on water supply and treatment “Central Public Health and Environmental Engineering Orangation” Ministry of urban development, NEW DELHI MAY,1999 Chapter 2. 2.2.8.3 Recommendation “Rainfall -Runoff studies in URBAN are using geographic information system and storm water management model. By SANTOSH KUMAR SADAM -2015 “Project on supplying drinking water from reservoir to Bhavani colony”

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