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Sewerage and Water Supply Systems Design for a city with large floating Population (Haridwar, India) using GIS K.Venkatarao, Er. U.B.Chitranshi & Dr.O.P.Dubey Civil Engineering Department, IIT Roorkee, India – 247667 ABSTRACT. The infrastructure of a city, mainly the water supply and sewerage system are vital for the urbanization. The present work provides a methodology of planning, design and project new pipes in water and sewer network. The existing infrastructure is studied using the GIS tool ARCGIS, this helped in the demand estimation from the land use information which is collected and stored in the Geographic Information System (GIS). In order to get these demands, a topology operation has been made by GIS. The future demand is forecasted depending upon the Demography and land use of the study area (Haridwar). An overlay between the land use topology obtained from the development plan and the tessellation to divide the served area among all the nodes where the demands must be loaded. The programming tool EPANET is used for the hydraulic analysis of the water pipe network. However, most of the existing algorithm needs a demand at nodes and existing physical dimensions of the network to perform the calculation. This data is imported from the ARCGIS tool which is stored in the Geographical Information System; through this the problem of sizing has been studied. This helps in completing the problem of creating new pipes for existing and future connections. The scope of the work is limited to the development of model for Water and sewer network for the City with large floating population (Haridwar). INTRODUCTION GIS has been regarded and proven as an efficient and powerful tool in the water distribution industry. According to American Water Works Association, 90% of water agencies are now partially using GIS to assist their daily operation. The business operations in the water/wastewater industry requires the District to keep complete and detailed inventory, including location and condition of all assets such as water mains, valves, hydrants, meters, storage facilities, sewer mains, and manholes. GIS is a state-of- the-art technology capable of efficiently performing all these data- related processes. [1] Haridwar town is a district Head Quarter of Uttaranchal. It is situated in foot hills of Shiwalik Range mountains is on 29°-58' north latitude and 78°-10' East longitudes and lies on the right bank of river Ganga. The town is most important pilgrimage centre of Northern India, where people from all parts of the country congregate every year to have a holy dip in the river Ganga. People in lac visit this place on Baisakhi, Somvati Amavasya, Ganga Dusehra, Shivratri, Kanwar Mela, Kumbh Mela and other small and big festivals. Data for water supply and sewerage network management: It is gathered in three main groups depending on its origin and its later usage. These groups are, basically, infrastructure information, customer’s information and geographical information about both infrastructure and customers. Element Data The information about network elements includes basically
Spatial information Finally, spatial information was usually scattered in various topographic and thematic maps. Some of the attributes, which appear in those maps, are:
Demand pattern prediction using GIS The knowledge of water demand on each zone is needed for pipe sizing. As it is a new implantation zone, water consumption must be estimated based on water duty or historical data of similar zones. This estimation can be obtained with two different techniques:
Another aspect for which the use of a GIS may be a good help is for the distinction of the demand type depending on the land use. It is advisable to start from a geographical distribution of the different land uses. For every one of the different land uses a consumption factor in terms of liters per second and hectare can be defined based on the statistical analysis of historic records. In this way, the expected demand in each node can be calculated as:  In this equation,qi is the consumption factor for a given land use i, Ai is the surface of that land use (l/s) the area served by a given node and Q is the total demand expected in that node. As a consequence of these analysis, customer, house connection, street or zones demands can be estimated. [5] Pipe sizing
BASE MAP PREPARATION Haridwar Tour Guide map (SOI) 1: 20,000 Layout of water supply network of Haridwar 1:12,000 Layout of sewerage system of Haridwar 1:12,000 Layout of camp sectors of Haridwar 1: 12,000 Haridwar district map 1: 1, 00,000 A GIS Base map is prepared by using above data, after earth curvature correction is made and used to further study. The city is divided into five zones to supply water supply and to provide sewerage system. These sectors and zones are made with the help of the Base map.(See figure 1) EXIXTING SITUATION Water supply system Water supply was first introduced in this town in 1927 and since then about ten times its reorganization augmentation has been done. Raw water is abstracted from the groundwater source (Tube well/Infiltration well/Open well).The water is pumped through rising mains directly to distribution mains. See Figure (6) The Main Components of the System
Consumption Pattern
Discharge
The data collected from various sources of water supply department of Haridwar (Haridwar Development Authority, Jal Nigam) is feeded as the input in the GIS tool ARCGIS. The Existing sources of water (Infiltration wells/Tube wells/open wells) are located and their discharge, type of pump installed, the head available and power of pump is updated in ARCGIS.  Figure 1 - ARCGIS Window showing Existing Water Supply System of Haridwar DEMOGRAPHY The growth of town largely depends upon the population studies. Through these studies one can assess the future land requirements, amenities and facilities and various other requirements of the city. Hardwar is an important Pilgrimage of Hindus. So throught the year pilgrims from all over India visit for holy dip in Ganga and on Parves millions of them assemble here for this purpose the demography profile can be provided into three parts 1) Permanent population, 2) Camping population and 3)Floating population. The permanent population of Haridwar union as per 2001 census is 177509. Camping population Besides the permanent population Haridwar has a floating population, mainly pilgrims, for 8 to 10 months. From March to October the average camping population 1, 00,000 to 1, 25,000 per month. Floating population Floating population consists of pilgrims, patient’s tourists (Indian and foreigners both), visitor’s sight seen. On special occasions such as on Makar sankranti in winter and Baisakhi in summer when 5, 00,000 to 10, 00,000. On the main mela day (Kumbh Mela 1998) total floating population were 51,00,000 people.(Haridwar development Authority) WATER DEMAND Rate of water supply and water requirement for the zones The rate of water supply in Hardwar Town has been taken @ 135 lpcd for permanent population, @70 lpcd for camping population and @27 lcpcd for floating population as per manual of water supply and treatment government of India, 15 to 20% losses in distribution system are anticipated. Therefore 15% losses have been accounted in this estimate for year 2005, 2020 & 2035. [7] Should be designed for a minimum waste water flow of 100 liters percapita per day. [6] DESIGIN OF WATER DISTRUBUTION SYSTEM The requirements for the distribution system are classified as; functional and hydraulic. A geometrical configuration of pipes, reservoir and boosters, selection and proper provision of valves, etc., for efficient distribution and maintenance and overall economic in cost constitute some of the function aspects. Adequate residual pressure at maximum demand depends upon the hydraulic capacity of the system. System Pattern The topography of Haridwar is uneven, doesn’t allow fol lowing one system. Here it is followed a mixed system (grid pattern, dead ends, tree system). System of Supply In Haridwar water is conveyed both by gravity-cum-pumping, water is pumped into the distribution mains from the source (wells) and to the elevated storage tanks. Minimum size of pipe at Haridwar is 80mm. The distribution pipes are provided on both sides of the road, by running rider mains suitably linked with trunk mains. In Haridwar the pipe lines are layed along the road. HYDRAULIC NETWORK ANALYSIS For the Hydraulic analysis EPANET computer programme is used for network analysis. The Hydraulic analysis is carried for one of the zone of Haridwar using EPANET. The zone ‘A ‘ Bhopatwala is taken for the analysis. The solution for heads and flows at a particular point in time involves solving simultaneously the conservation of flow equation for each junction and the Headloss relationship across each link in the network. This process, known as “hydraulically balancing” the network, requires using an iterative technique to solve the nonlinear equations involved. EPANET employs the “Gradient Algorithm” for this purpose. A network is drawn representing the Bhopatwala Zone ‘A’ by taking the data from the Base map prepared by ARCGIS into the EPANET. [10] Physical Components in a Water Distribution System Junctions, Reservoirs, Pipes, Pumps, Valves and Tanks. Junctions are points in the network where links join together and where water enters or leaves the network. This data of elevation taken from the ARCGIS MAP representing the water supply network from (figure 2). The demand of water supply at a node is calculate using the floor space and the sector population at present (See Table 1). These values are entered as input at every junction and it is shown by an attributes in ARCGIS.  Figure 2 - The ARCGIS window showing water supply system on a TIN Surface EPANET models a water distribution system as a collection of links connected to nodes. The links represent pipes, pumps, and control valves. The nodes represent junctions, tanks, and reservoirs. The (figure 3) below illustrates how these objects are connected to one another to form a network. The output results computed for junctions at all time periods of a simulation are: The Run of the simulation for the Bhopatwala sector is successful; its output analysis is given in the (Table no 2) In the Bopatwala zone the water reservoirs are (Infiltration wells/Tube wells/Open wells). The primary input properties for a reservoir (infiltration wells/tube wells) are its hydraulic head (equal to the water surface elevation if the reservoir is not under pressure) these values are also taken from the attribute tables from the ARCGIS.) Water supply map and its initial quality for water quality analysis.  Figure 3 - EPANET window Showing the Pipe network, wells, Tank and pumps of the Bhopatwala Zone 
Table 2 - Showing the output of Head (m) and Pressure(m) of Bhopatwala zone 
In the Bhopatwala zone there is one tank of capacity of 270 Kiloliter, its bottom elevation, diameter, initial and maximum level are given. 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. In the Boopatwala zone all the exixting pipe lengths, diameter, type of material, start and end nodes are taken from the attribute tables of exixting water supply system which is prepared by ARCGIS. The information from the GIS is feeded as the input to network drawn in the EPANET (See table no 3). As the hydraulic analysis carried using the Haznes Willams formula the roughness cofficents is taken as 100. The existing pipe are given there dimensions (length & diameter) are entered. The output of the hydraulic analysis is given in the (Table No 4) 
Non-Physical Components In addition to physical components, EPANET employs three types of informational objects – curves, patterns, and controls - that describe the behavior and operational aspects of a distribution system Curves Curves are objects that contain data pairs representing a relationship between two quantities. Two or more objects can share the same curve. An EPANET model can utilize the following types of curves:
WATER SUPPLY FOR THE CAMPING POPULATION In Haridwar there are eight sectors which are providing Camping for the Pilgrims, for the various festival occasions. It is required to supply water supply to these sectors. So it is important to know the source location (present existing distribution) from where it can draw water for the sector demand. The demand is calculated from the built area of the camp sector. The GIS information which is available can be used for identification of the exixting pipe lines and laying new lines for the camp sectors and to calculate the hydraulic analysis of the new network. Therefore planning is very easy to provide camping facilities to floating population to Haridwar Existing Sewerage System Sewerage system was introduced in Haridwar in 1938. Since than it has been entered to various parts of the town. At present 90% of town is covered with sewer system. In the last sewerage project is divided into five zones depending upon the topography and capacity of old works. Component of Sewerage System
Present Treatment Facility Capacity Total amount of sewage generated per day is 40.09 MLD (i) Total capacity of treatment plants 27 MLD (ii) Amount of untreated sewage 13.09 MLD (iii) Population not served by sewer system 40,000 The data collected from various sources (Ganga Pollution Control Board, Haridwar Development Authority) stored in the ARCGIS. (See figure 4).  Figure 4 - The ARCGIS Window Showing the Details of Existing Sewerage System of Haridwar, Sewage Pumping Stations (SPS) Sewage Treatment Plant (STP) Sewer Network COMBINATION OF GIS FOR SEWER ENGINEERING The data collected from various agencies for sewerage system of Haridwar is transferred into the ARCGIS. The planning essentially comprised of Data collection coupled with a detailed scoping or pioneering with the following aim. (i) To determine the extent and physical properties or dimensions of the sewerage system(including location of manholes, sewage pumping stations, treatment plant and surfaceflow drains and culverts which effect the sewer system) (ii) The hydraulic characteristics of the system, to identify the existing discharge points, to review all known operational problems and deficiencies within the sewerage system (iii) To identify the existing discharge points. (iv) To review all known operational problems and deficiencies within the sewerage system. (v) To evaluate potential options and solutions to overcome the problems whilst increasing the capacity of the system to cater for the future growth of the expansion. (vi) To outline programe for the development and implement of solutions. [9] NETWORK IDENTIFICATION The ARCGIS enable us for the easy identifications of the existing sewer,its length, diameter and hydraulic of the system. The topography of the Haridwar is un even and all the regions don’t have a required slope. Therefore it is required to have the sewage pumping in some areas. In the zone ‘A’ Bhimagoda it has enough slope, ther efore the sewage is collected through a gravity trunk of diameter 600mm.it was required a sewage pumping stations at Bhimgoda after collecting by gravity trunks as the topology don’t permit slope to reach the treatment plant which is suitated at Jagitpur. A rising main was provides from Bhimgoda to Mayapur bridge, from were it again carried by gravity.The length and diameter of the exixting system with sewage puming stations locations are easily identified. The disharge points are located and identified in the sewer network. The quanity of sewage generated is calculated depending upon the population of the sectors. The elevation of the pipes and its slope is known from the GIS information, the information is managed by ARCGIS tool, the slope, elevation, length of pipe and material are taken from the data of GIS information of sewerage system of Haridwar. Slope and elevation are known from the TIN surface. The available information from GIS can be carried out for the sewerage engineering of this zone. The required elevation and slope can be found out from the TIN surface. The discharge points are easily located, and its flow is easily calculated by the population of that sector. Location of the sewage pumping station and the sewage treatment plant known gives a shortest path which minimizes the cost of the sewer. CAMP SECTORS SEWERAGE FACILITIES There are eight camp sectors in Haridwar for the pilgrims. The camps sector of Haridwar is provided with the sewerage facilities, this is temporary facilities which the sewer lines are laid and dismantle after use period of a particular festival. The camping population should be provided with sewerage facilities, the sewage discharge from these points should be known. The sewage collected from these sectors should be reaching the treatment plant. The GIS information provides with information of the existing sewer and Manhole, the topography, discharge of the points which can be to propose a new sewer to connect to the existing system after the hydraulic analysis. CONCLUSIONS
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