UTILIZATION OF AVAILABLE WATER RESOURCES IN UTTARANCHAL: AN APPRAISAL OF CURRENT STATUS AT THE DISTRICT SCALE INTRODUCTION

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1 UTILIZATION OF AVAILABLE WATER RESOURCES IN UTTARANCHAL: AN APPRAISAL OF CURRENT STATUS AT THE DISTRICT SCALE V. N. Sharda and P.R. Ojasvi* INTRODUCTION The study on water as a natural resource is inclusive of its hydrologic components and extraction demands imposed by human and animal population. A hydrologic analysis covering both the supply and demand factors is extremely important for planning and decision making for sustainable development of water resources in the hill regions. The utilization of available water depends upon the magnitude of infrastructure development in a region. The infrastructure may include wells, handpumps, tubewells, piped supply, tanks, lift schemes, springs, infiltration wells, canals etc. The policies for investment and management of water resources, therefore, have to take into account the current utilization pattern and future requirements for development depending upon the water demand estimates. A study was undertaken for the assessment of present status of water availability and its utilization pattern based on the different sources of water supply in operation in district Tehri- Garhwal. The water sources are broadly classified as natural sources and man-made mechanical sources. Study Area The State of Uttaranchal covers a geographical area of 53,485 km 2. The region being situated centrally in the long sweep of the Himalayas forms a transitional zone between the perhumid eastern and the dry to sub-humid western Himalayas. The region comprises of two administrative units, viz.; Garhwal (north-west portion) and Kumaon (south-east portion). Like all other parts of the Himalayas, the Kumaon and Garhwal regions are also heterogeneous in several aspects, representing a wide variation in topography, altitude, rainfall and vegetation characteristics. Factors such as elevation, slope, aspect, proximity to glaciers, forests, mountain peaks and ridges and direction of mountain ranges together are attributed to large variations in climatic conditions, even at the micro and local levels these factors determine the temperature range as well as the distribution of rainfall. The frontal ranges of the Shivalik and adjoining Lesser Himalayas receive highest amount of rainfall of about 242 cms, followed by locations close to Greater Himalaya (216 cms), foothills (188 cms), Terai locations (144 cms) and the rain shadow locations of Trans-Himalaya (72 cms). * Director and Sr. Scientist (Eng.), respectively, Central Soil & Water Conservation Research & Training Institute, 218, Kaulagarh Road, Dehradun

2 2 The monsoon commences after the middle of June and continues till mid-september, by which time about four fifths of annual precipitation is generally received all over the region. Tehri Garhwal is one of the western most district of Uttaranchal State located on the outer ranges of the mid Himalayas. The district lies between and N latitude and and E longitude. Uttarkashi from the north, Rudraprayag the from the east, Pauri Garhwal from the south and Dehra Dun from the west are the bounding districts. On the western front Yamuna river separates it from Jaunsar Pragana of Dehra Dun district while Bhagirathi rising from the north of Gangotri in district Uttarkashi touches the district near village Nagun. Total area of the district is 4421 km 2. A major portion of the district is having hilly tract. The plain area is more fertile than the hilly area. Bulk of the area of the district is under forests, which plays a vital role not only in the ecology but also in the economy of the district. These forests are rich in biodiversity. However, there has been a large scale denudation of forests in the past, resulting in impoverishment of forests wealth. Normal annual rainfall in the district varies from 1015 to 2630 mm. The block-wise population (rural) and agricultural area along with the irrigated area in Tehri district is given in Tables 1 & 2, respectively. Percentage Decadal variation in population since 1901 is presented in Table 3, which shows that recent population growth rate in the district is as high as 16%. This is important from the point of view of estimating present and future water demands. Table1. Block-wise human and animal populations (rural) of Tehri district S. No. Block Number of Villages (1991) (2001) decadal growth (%) Animal population (1993) (2003) Decadal growth (%) 1. Bhilangna Chamba Devprayag Jakhnidhar Jaunpur Kirtinagar Narendranagar Pratapnagar Tholdhar Total Table 2. Block-wise statistics of agricultural practices in Tehri district S. No. Block Area (km 2 ) Net sown area (ha) Net Irrigated area (ha) Gross Irrigated area (ha) Percentage irrigated area (%) 1. Bhilangna Chamba Devprayag Jakhnidhar Jaunpur Length of canals (km)

3 3 6. Kirtinagar Narendranagar Pratapnagar Tholdhar Total Table 3. Percentage Decadal variation in population since 1901 State / Percentage decadal variation District Tehri Garhwal Uttaranchal Data and Procedures A survey of drinking water supply status in rural habitations of uttaranchal was carried out by the Department of Drinking Water Supply, Ministry of Rural Development, Government of India during The survey was carried out by district development agencies. The guidelines for the survey have been formulated in such a way that maximum information on ground realities can be ascertained within limited time frame and with minimum cost. The survey covered rural habitations in the district and data on various aspects such as population of village, source/type of water supply, population covered by water supply, number of working and defunct safe water supply systems, details of existing sources of water and their discharges were collected. The relevant raw data of this district survey was collected from District headquarters and has been analyzed for water utilization patterns. Water Demands Various water demands in a region primarily include human, animal, agricultural, industrial and environmental water requirements. The agricultural and industrial demands together consume approximately more than 70% of the total developed water resources in a given region. However, the first priority of National Water Policy is to provide safe water to all rural habitations. This is one area of rural development schemes and water resources management where no compromise can be made. The safe availability of water for public consumption includes human, animal and public institutions such as schools, hospitals, panchayats, courts, banks and other offices. Daily water requirement of these consumption sources varies as per their characteristics. Therefore, some standard average requirement is used for estimating the total water demand. Recent population of these consumption sources in Tehri district is given in Table 4. Daily requirement for human consumption is taken as 40 lpcd. For animals, the daily requirement varies from 1-60 l/day with average of 15 lpcd. For public institutions, the requirement ranges from 20 l/day (for example post offices) to 1400 l/day (hospitals/schools). The expected demand of water for the entire district including rural and urban areas is presented in Table 5. When water supply systems function satisfactorily and there is subsequent enhancement in living conditions and income levels, people are often willing to pay for improved service levels and will use drinking water for other domestic and economic purposes. Therefore, during the design life of a system, the average per capita water consumption increases if the system functions well. On

4 4 the basis of these projected figures, it can be estimated that if the goal of clean water for all is to be reached, the daily consumption of clean and reliable drinking water could be multiplied by about 2 or 3. Management of water resources and protection of sources is, therefore, essential to ensure sustained and safe supply of water. Table 4. statistics of Tehri district (as per the most recent data) State / District 2001 density per sq. Km. Animal population Public Institutions Persons Males Females (1991) (2001) (2003) (1997) Tehri Garhwal Uttaranchal * * Data pertains to base year 1997 Table 5. Expected demand of water for consumption of different sources Demand Source Water demand (Kld) Human Animal 5873 Public institutions 408 Total Water Infrastructure Water sources available in the district can be generally divided into groundwater and surface water sources, springs and rainwater (Table 6). Considering the various types of water sources, it is desirable to make a distinction between small and large sources useful for determining the nature of source-catchment linkages. Small and medium size systems include wells, boreholes with handpumps, spring captation systems, small piped and pumped water supplies, and gravity water supplies. Such systems serve a variety of communities, including rural villages and townships, regional centres, as well as urban low-income areas and urban fringe settlements which are not connected to urban drinking water supply networks. The captation system is a part of the water supply systems while source selection is a part of planning and design. Water source protection aims at not only ensuring the reliability of the source, but also contributes in its improvement by increasing the quality and quantity of the water, or diminishing fluctuations. This may render the source adequate for different uses and reduce the costs of the water supply system.

5 5 Table 6: Types of Water Sources Source Category Captation Groundwater in aquifers Surface water confined unconfined shallow fossil gravity artesian River streams lake ponds shallow well borehole deep well spring box open intake infiltration gallery traditional systems Direct pumping dam, infiltration well riverbed filtration open intake, guhls Rainwater NA Rooftop harvesting surface catchment runoff farming Water quantity of a source is sufficient when the lowest yield from the source meets the daily demand. This demand is normally determined by the daily per capita consumption for a given population. It is generally accepted that a minimum of litres per capita per day should be provided, but in many areas such as remote habitations or hill tops lower limits can be set. This illustrates that in determining sufficiency of water quantity, much depends on local water use habits, which are influenced by environment, socio-economic status, and socio-cultural factors. Nonetheless, the existing water utilization infrastructure in Tehri district is given in Table 7. The captation system is further grouped in to man-made and natural systems based on the skills required in their installation, cost of operation and maintenance and system s proximity to natural and social settings. Table 7. Details of existing water utilization infrastructure in rural areas of Tehri district Man-made Captation systems being served Design Quantity (kld) Total Discharge Maximum (lpm) Minimum (lpm) Deep Hand Pump Shallow Hand Pump Surface water Power Pump Tube well Power Pump Natural Infiltration Gallery Infiltration Wells Traditional Sources Others

6 6 Water Utilization The current water utilization pattern in the district can be assessed based on the quantity of water being used from each capitation system. Table 7 reveals that more than 86% of the water demand of human population is met by natural resources, 8% by power pumps and rest by hand pumps. This reflects upon the choice of technology and category of water sources that should be emphasized in future planning and design. Data on defunct systems indicated that more than 99% of defunct services are under natural system category (Fig. 1). Although natural resources serve the majority of population and their water demand, they are the most mismanaged systems The causes for dysfunctional schemes are a mix of natural and human factors, later being more responsible. Some of the reasons identified for dysfunctional water supply schemes aredeclining trend of water availability at the source due to land degradation and deforestation; non-involvement of local community; no specific mechanism for operation and maintenance of schemes by government agencies; non-availability of local services and lack of technical know-how for maintenance initiative by local people or Gram Sabhas. At the maximum level of available water, about 70% contribution to total water demand is by natural resources, 28% by power pump based schemes and only 2% by hand pumps. At the minimum level of available water, more than 78% contribution is by natural sources (as compared to 70% contribution in case of maximum availability) while contribution by power pumps reduces to 20% (a decrease of 8%) (Fig. 2). No appreciable change in contribution occurs by other means. This shows the reliability of natural captation systems vis-à-vis fluctuations in water availability of various sources. At the minimum level of available water, demand deficit level varies from 46% to 87% in the case of man-made systems. Deficit levels are as low as 35-37% in case of springs and infiltration gallery (natural sources) in spite of the fact that large numbers of these sources are defunct. Surplus availability is shown in case of deep tubewells, infiltration wells, traditional and others sources (Fig. 3). The water deficit levels have been analyzed based on the demands of human population only. CONCLUSIONS The choice of a water source should ideally be based on data related to water quality and quantity, and on a realistic assessment of possible source problems and feasible protection measures. Insufficient data or unrealistic assumptions made in the planning phase are the primary causes of major problems at the source. Insufficient consideration is given to possible changes in the catchment areas due to human activities. As these changes are often not monitored and land-uses not controlled, deterioration of water sources is occurring widely without being recognized. The utilization patterns of available water give provide a vital information on the magnitude of infrastructure development in a region. The policies for investment and management of water resources, therefore, have to take into account the current utilization pattern and future requirements depending upon the water demand estimates. Profiles of different types of water sources in different environments and their vulnerability to environmental factors could form a basis for decision-making. Establishing parameters for the monitoring and evaluation of surface and sub-surface sources under different catchment conditions and developing checklists of remedial and preventive solutions would form a starting point for engineers and planners. These decision making tools are considered essential for the development of water source and its protection.

7 Number of Defunct Services 7 1% 69% 20% 0%1% 0% 9% 0% Deep Hand Pump Surface water Power Pump Infiltration Gallery Others Shallow Hand Pump Tube well Power Pump Infiltration Wells Traditional Sources Fig. 1. The percentage of defunct water captation system in Tehri district Minimum available water (kld) 21% 0% 20% 50% 1% 0% 1% 7% 0% Deep Hand Pump Surface water Power Pump Infiltration Gallery Others Shallow Hand Pump Tube well Power Pump Infiltration Wells Traditional Sources Fig. 2. The contribution of various water captation systems at minimum water discharge Percent Demand Deficit at Minimum Available Water Deep Hand Pump Surface water Power Pump Infiltration Gallery Others Shallow Hand Pump Tube well Power Pump Infiltration Wells Traditional Sources 18 Fig. 3. Water deficit levels at the minimum available water for various systems