Domestic Water Supply And Ground Water Use in Nagpur City Final Report Principal Investigator Co-Investigators

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1 Domestic Water Supply And Ground Water Use in Nagpur City A Socio Geographical Analysis Final Report Minor Research Project University Grants Commission, New Delhi January 2007 Principal Investigator Dr. Shubhangi Girgaonkar Co-Investigators Mrs. R. Padwad Dr. D. Chahande Introduction Urban areas in developing countries are growing faster than their counterparts in developed countries. It is estimated that by the end of the century urban population in developing countries will be twice that of the industrial nations and by 2025 A.D. it could be four times larger (Mammer, 1991, p.19). Consequently, various basic services, including water supply is unable to keep pace with this rapid growth rate of urban population. In the urban environment of many developing countries, water supply situation has indicated serious set back. It has been observed that investment in drinking water supply, treatment works and distribution network have not matched and unable to keep pace with population growth and socio-economic development (WHO, 1997, p. 97).

2 In urban areas timely and regulated water supply is considered necessary because people can not move far away places to fetch water for safety reasons and convenience of work (Mandal, 1999, p. 388). Per capita consumption of water has increased with time. This increasing consumption pattern has put heavy pressure on the water supply schemes. Sustainability of assured water supply to this ever growing demand therefore has become the core issue to the water supply planners. Deteriorating plight of urban water supply in India, especially during last two decades jeopardized the fate of many Indian Cities (Saxena, 2003, p.11). Unplanned development of slums and outskirt colonies further adds to the problem. Thus, intensification of inadequate water supply and water scarcity is an unpleasant reality in Indian towns and cities. Period and nature of water scarcity however differs in different regions and pose quite different challenges of varied nature. Though the government is managing the water supply schemes almost in the entire country, it has its own limitations. Consequently, substantial part of urban water supply is obtained by tapping sub surface sources. Resultantly water level in urban areas is going down and down with every passing year, causing alarm and may pose severe environmental problems (Saxena, 2003, p.11). This situation has arisen mainly because of our failure to ensure recharging of urban aquifers by harvesting rainwater, by reviving lakes and ponds in nearby areas (Saxena, 2003, p.11). Society and common man therefore need to be activated so that adequate water supply is ensured to every one, throughout the year. We therefore need to ask ourselves, why does no suitable mechanism exists which deals with the management of water, either surface or ground with the specific objective of sustainability. Objectives In the above context therefore the study has been proposed to focus on the following objectives - To analyse the salient trends of rainfall and its variability, as water availability depends on rain factor. To explore the present position of municipal water supply (domestic).

3 To examine ground water potentiality and hygiene quality of ground water. To examine the nature and consequences associated with inadequate water supply. To investigate the intensity of ground water use as the main or an alternative source of water supply.

4 To examine the public awareness regarding various water related issues including environmental consequences associated with the exploitation of ground water and their perception regarding the use of water harvesting structures. Database and Methodology only. The study is based on the primary and secondary data and confined to domestic use of water The primary data sources involved field based questionnnaire aided by interview of 1200 house-holds. Direct observation and intensive field investigations have generated primary data. Cases were randomly selected from all parts of the city including core, outer core and periphery areas. A well structured questionnaire comprising of both open and close ended questions has been used for conducting the survey. The data was collected during April 2005 to August The questions were mainly focused on the issues like awareness and nature of existing water supply, period, nature and intensity of ground water use, period of water shortage, their adjustment with summer water shortage, knowledge and perception of water harvesting and compulsory roof top water harvesting, their grievances about water supply etc. Such types of awareness and behaviour searching questions and dialogue were of great help in understanding various dimensions of domestic water supply, residential water use and public perception and consciousness about various issues of water. Many questions were thought provoking issues for the respondents. Seven ground water samples from different localities of Nagpur City were collected and tested in the Regional Public Health Laboratory, Nagpur for examining Physico-chemical quality of water.

5 Conclusions and Suggestions The forgoing discussion and analysis has been presented in four chapters. The rainfall of Nagpur City is assessed in Chapter 2, while present status of Municipal Water Supply was discussed in Chapter 3. Chapter 4 highlights the ground water potentiality and quality of ground water. In Chapter 4, findings of house hold survey have been analysed. On the basis of rainfall assessment of Nagpur City (Chapter 2) it is concluded that- The long term mean annual rainfall ( ) of the city is fairly reliable and dependable. However decadal rainfall analysis revealed rising inconsistency and instability of annual rainfall. This is an alarming situation from the view point of water resource management. The monthly rainfall is highly variable and inconsistent. However, the long term monthly rainfall analysis reveals a few very high rainfall values in every month. These are considered to be of great practical significance from the point view of rainwater management. Flood and drought years are randomly distributed, without any noticeable cyclic pattern. The city comes under the moderate drought prone zone. On an average there is a possibility of drought in every 5.5. years.

6 Lowering trend of rainfall is clearly visible. The decreasing trend of rainfall of 1.97 mm / yr has been reported. March, April and May are the months of very high water deficit. Discussion and analysis of present status of Municipal water supply (Chapter 3) reveals that Municipal Water Supply from the meager begining of 16 MLD (1931) has shot up to 490 MLD (2006). Pench Project located 48 kms from the city has become the major source of water supply to the city. Considering the future demand, city authorities are constantly in search of alternative sources, which are still farther from the city limits. However it is felt that supply from the distant sources will prove very expensive. Besides that it would also pose other challenges such as maintenance, vigilance and rural/ urban conflict over water. Per capita per day water supply to the residents is 135 liters. This falls short of the recommended standard of liters per capita per day. To fight with the summer drought situation, city authorities have constructed open wells and bore wells, in various water shortage localities. However, in many localities these water sources have proved to be a wasted resource as there is lack of maintenance.

7 Current problems of the water distribution system are loss of water (25 to 30%) through pipe line network and canal, damaged pipe lines, consequently water contamination in the old areas, water shortage due to pilferage, low water tariff, non functional water meters in households, high number of unauthorized connections, deficit budget etc. Experts opined that the entire process is un-economical. If not tackled urgently the city will face severe water shortage in the next 5 years. On the basis of analysis of ground water potentiality (Chapter 4) following conclusions have been drawn- Except few patches of very compact basalt and crystalline formation, hydro geological condition is very favourable for ground water exploitation. In the city depth of water level ranges between 3 to 9+ mtrs. b.g.l. However in the major part of the city, depth to ground water ranges between 3 to 6 mtrs. b.g.l. It was revealed that wherever ground water level is rich, get regular and twenty four hours of water supply and where it is poor have no drinking water network or very limited supply. Physico-chemical analysis of ground water indicates that except some localized patches, in general ground water is fit for drinking purpose. In some localities due to mixing of sewage water and nala water, ground water is endangered to bactereological pollution. Therefore, regular clorination is needed. However, this quality deterioration is generally location specific and is not true on regional scale.

8 Major findings of the household survey (Chapter 5) are Most of the respondents have floored their court yards fully or partially. Thus open space for rain water percolation is much less even at household level. Fridge, water coolers, washing machines and scooters are the most common costly articles in the households. Higher percentage of households have gardens or potted plants or both in their households. Besides piped water supply, higher percentage of surveyed households have their own water resources in the form of wells or tube wells. Therefore they do not experience water shortage except summer season. However it was observed that as soon as sufficient piped water supply is provided, wells - the dependable source loss their importance. Water supply in the city could not keep pace with the population increase as 12 per cent households have to depend on ground water sources only. Nearly 34 per cent households depended only on piped water supply. Their total water need is fulfilled through Corporation water. Thus wide disparity in water allocation has been noticed. Water demand at household level is continuously increasing. Nearly 45 per cent respondents were not fully aware of water sources to the city. Thus level of awareness amongst the people is poor. Severe disparity in the duration of water supply (3 to 20 + hrs) has been noticed. Except few households, water shortage is not felt by the residents, except during summers, because they supplement day to day municipal water supply by the sub-surface sources. Summer water shortage aggravates and becomes severe, when there are subsequent dry years. In general April and May are the months of severe water shortage. Some of the respondents leaving in the outer core and the peri urban zone suffer from water psychology. However in general adjustment capacity of people to fight with the summer water shortage is good. It is the favourable situation to make the water supply sustainable.

9 Most of the respondents agreed to limited hours (1 to 2 hours) of water supply with full force, throughout the city to avoid wasteful domestic use. Common grievances of people about the existing water supply are - low water pressure, no proper billing of water charges, no timely arrival of tankers, ill maintenance of public wells and hand pumps, unlimited water supply in the favaoured localities, no charging of pipeline network of newly established areas. At household level dug wells are the most common ground water extraction structures. Density of wells in outer core and peri-urban areas is very high. In many areas due to over exploitation of water ground water is under stress. Peoples perception indicates falling ground water level. Higher percentage of respondents accepted that they had to deepen their wells for want of water. Thus wherever exploitation is high natural replenishment of water is poor. However falling of ground water level has not been reported in the areas located in the close vicinity of lakes. In general people are unaware about the purpose and methods of water harvesting. Their knowledge of water harvesting is limited to terminology only. This shows poor level of awareness on this major issue. People are not aware about the rebate provided to them by Nagpur Municipal Corporation on house tax, if rain water harvesting structure is built at household level. Higher percentage of respondents responded positively in favour of constructing roof top water harvesting structure. Suggestions The overall picture that emerges from the study is that water shortage in the city is confined to summer season only. It is mainly caused by highly uneven allocation of Municipal water, poor management and piped water distribution without considering ground water potentiality. Therefore it is suggested that :-

10 Instead of harnessing distant expensive water sources, it is felt that real solution lies in the judicious combination of the surface and ground water with planned use of water harvesting techniques. It is the first step towards achieving sustainable water supply in the city. Use of water harvesting technique is to harness full potentiality of rainy season, wet years and few high rainfall incidences of dry months. It is considered very urgent as Nagpur city experiences decreasing tendency of rainfall. Public participatory water harvesting programmes should be persued at various parts of the city, particularly in the areas where ground water utilisation is high. Building plans should not be sanctioned without the provision of water harvesting structures in the ground water depleted areas. In already constructed buildings it should be made mandatory (as in Chennai). All the unused wells of the city should be urgently cleaned and well maintained with public and private sector participation to be used during dry period. Revival and rejuvenation of lakes of the city (total 6) is one of the most important practical measure.

11 Now the time has come to achieve sustainability in water supply through stringent measures, particularly in the context of deficit financial budget of the Water Works Department. Water should be supplied with high pressure for short duration to minimise the waste and misuse of water, instead of long duration and twenty four hours supply. Limited short duration municipal water supply for drinking purpose while sub-surface sources for other domestic activities may give better results, especially in areas where ground water use is minimum. People should be encouraged to use ground water for routine domestic work. This may lessen the burden on municipal supply. The Water Works Department should also think of a well planned and thought out long term measure, which may find immediately costly, but in the long run cost effective, that is supply of two types of water to residential areas, one for drinking purpose which should be in limited quantity, while supply of raw water for regular domestic use to avoid water filtration and treatment cost. Creating awareness is the most effective means of generating involvement of residents through which sustainability can be easily achieved. The urban community need to be made water conscious. Reducing demands through water consciousness and inculcating conservation attitude in urban community is an urgent need to achieve sustainability in water supply. It is essential to make the people aware of the status and various issues in water sector including distance of water sources and economics of treated water supply, water harvesting through print and electronic media, film shows, charts, models, road side hoardings and through regular sharing of information. Suggestions provided by the respondents are outlined in Table 14.

12 Table 14: Suggestions Provided by Respondents There should be uniform distribution of water supply throughout the city. Water supply hours of the civil lines area should be reduced. Water supply hours should be at day time only. Night time supply should be avoided. Timings should be fixed for localities. Schedule time of water supply should be maintained. There should be restricted water supply for 1 to 2 hours with full force throughout the city. Nagpur Municipal Corporation should maintain water pressure, so that overhead tanks will be filled. Leakage of taps and pipelines should be immediately repaired. Keeping in view the summer water scarcity Water Works Department should start water rationing well in advance. Regular cleaning of water tanks should be undertaken. Motor attachment to corporation tap should be checked regularly by inspectors. Heavy fine should be imposed. Public stand post should be regularly checked to avoid wastage of water. Number of hand pumps and public wells should be increased in the water scarcity zones. Hand pumps and public wells should be dug in every colony. As per the requirement of area Nagpur Municipal Corporation should make the water harvesting structure mandatory. Instead of making water harvesting structure mandatory, it is to be done through awareness programmes. Source : Field work