Anupma Sharma1, Om Prakash Sharma2, N.C. Ghosh1 and K.D. Sharma3*
Effective management of problems related to growing water scarcity in arid/ semi-arid regions calls for suitable adaptation and mitigation measures. Jaisamand Lake Basin, located in the State of Rajasthan, India, is a candidate pilot basin under the Asian G-WADI program. The basin characterized by semi-arid climate and underlain by hard rock formations is predominantly inhabited by poor tribal communities, surviving on meagre resources. The impact of growing water scarcity on the natural and social systems within the basin is severe. To effectively cope with the water scarcity, adaptation measures are being taken at the individual/community level to mitigate the adverse impacts of droughts, develop the water resources, stabilize agricultural production as well as reduce the community’s vulnerability to water shortage. These measures include changes in existing practices and implementation of suitable technology with a view to take the maximum advantage of the limited opportunities offered by the climatic conditions of the semi-arid region and the hard rock terrain. The paper describes how the adaptation and mitigation measures in the Gangeshwar macro-watershed of the basin have facilitated easy access and availability of water for drinking and irrigation purposes.
KEYWORDS semi-arid region, adaptation and mitigation measures, water scarcity, water harvesting, soil and water conservation, capacity building
All across the world, the concern for water resources is growing as a result of population growth, climate change, and alarming signs of groundwater depletion at an unsustainable rate. In semi-arid and arid regions groundwater is a vital natural resource which is increasingly being tapped as a reliable source of water supply to meet the growing demand for water. In most regions of water scarcity (except extremely arid tracts), the shortage of water is not caused by low rainfall as is normally perceived but rather by a lack of capacity for sustainable management and use of available water resources.
1 National Institute of Hydrology, Roorkee 247 667, India
2 Wells for India – India Liaison Office, Udaipur 31 3002, India
3 National Rainfed Area Authority, New Delhi 110 012, India ([email protected])
Rajasthan is the largest State in India covering an area of 342,226 km2, i.e. 10.5% of country’s geographical area, has 5% of its population, yet only 1.15% of its water resources (GOR, 2005). About 60-75% area is semi-arid or arid with annual rainfall ranging from 100 mm in west to 950 mm in southeast. The Aravalli Mountains, comprising alternating hill ranges, traverse the state in NNE-SSW direction almost from end to end dividing the State in two unequal parts, three-fifths of which constitute the western arid Rajasthan and two-fifths constituting the eastern semi-arid region.
In the last five decades, a threefold increase in human population and a doubling of livestock population has put tremendous pressure on the water and land resources of the State. The estimated annual per capita water availability in the State during 2001 was 840 m3 and it is expected to reduce to 439 m3 by the year 2050, against the estimated national average of 1140 m3 by 2050 (Narain et al., 2005). Recurring droughts are a common phenomenon exacerbating the water shortages. The seasonality and variability of rainfall necessitates construction of dams, tanks and ponds to meet irrigation and drinking water requirements round the year.
Due to scarcity of surface water, the State has to depend on groundwater resources to a great extent. Approximately, 40% of Rajasthan is occupied by hard rocks in which the groundwater resources are limited; however, the valley fills consisting of river and stream laid deposits, often contain productive aquifers. The depth to water varies from less than 10 m to 25 m in eastern parts whereas in western parts it ranges from 20 m to 80 m. Since 1951, the area under irrigation using groundwater has remarkably increased and at present about 60% of the total irrigated area depends upon groundwater. However, the overexploitation of groundwater coupled with inadequate replenishment has led to depletion in water levels in about 67% area of the State over the years (SRSAC, 1999). Effective management of problems related to growing water scarcity calls for adaptation and mitigation measures especially in pockets under severe water crisis.
UNESCO’s program for ‘Water and Development Information for Arid Lands – A Global Network’ (G-WADI) has the strategic objective to strengthen the global capacity to manage the water resources of arid and semi-arid areas. This paper discusses the adaptation and mitigation measures taken up in the Jaisamand Lake Basin in Rajasthan – a candidate pilot basin under the Asian G-WADI program.
JAISAMAND LAKE BASIN: SEMI-ARID BASIN IN INDIA
The Jaisamand Lake Basin is located in the semi-arid region in Udaipur District of Rajasthan. Portions of five administrative blocks, i.e. Girwa, Dhariawad, Sarada, Salumbar and Vallabhnagar, in Udaipur district fall within the basin (Fig. 1). The basin is bounded by Longitude 73045′ E to 74025’E and Latitude 24010′ N to 24035′ N. Jaisamand Lake with a gross capacity of 414.6 Mm3 and live storage of 296.14 Mm3, is the largest water storage reservoir in the area. River Gomti with its tributary Jhamri is the major river which drains into Jaisamand Lake. Jaisamand is a prominent medium irrigation project with a culturable command area of 160 km2 downstream of the lake. The gross basin area upto the Jaisamand dam site is 1787 km2. The lake is also a prime source of water for the city of Udaipur located at a distance of about 52 km from the lake.
Fig. 1 Jaisamand Lake Basin
The area is marked by hilly terrain belonging to the Aravalli Mountain chain. Ground elevations in the basin range from +300 to +650 m above mean sea level approximately. The average annual rainfall is 652.6 mm. The rainfall during the monsoon months of June to September constitutes about 94% of the annual rainfall. Annual potential evapotranspiration is 1380 mm. The rivers and streams in the basin are non-perennial and flow only during the rainy season.
The basin is predominantly inhabited by tribal communities. About 30% of the population lives below the poverty line surviving on meagre resources. The principal activities that support the livelihood system are agriculture, animal husbandry and wage employment. Forests also contribute significantly in the form of fodder, fuel wood and non-timber forest produces. However, lack of sustainable food and fodder security system and non-availability of non-farm based economic activity gets aggravated during droughts. Successive drought years coupled with human interventions such as exploitation of groundwater and increase in population have emerged as a major threat to the resource bases and livelihood system. All in all, scarcity of water together with lack of proper natural resource management have resulted in degradation of land and water resources, and, poor social and economic conditions in the basin.
Groundwater is the major source of water supply in the region underlain by hard rock. Most parts of the area have potable groundwater. Saline groundwater exists in small patches of Vallabhnagar block while high fluoride content is present in some parts of Salumbar and Sarada blocks. Table 1 shows that the main source of irrigation in the area are wells (irrigated area 86.4%) followed by ponds/tanks (irrigated area 13.2%).
Table 1. Source-wise net irrigated area (2002-03)
|Block||Net Irrigated Area (km2)||% Irrigated Area|
Source: Statistical handbook of Udaipur district (GOR, 2004)
MEASURES TO COPE WITH WATER SCARCITY
In a water scarce region such as Jaisamand Lake Basin, water availability has a direct impact on livelihood security such as food availability, animal husbandry and forest produce. To effectively cope with water scarcity, adaptation measures need to taken at the individual/ community level to develop the water resources in a sustainable manner in order to mitigate the adverse impacts of droughts, stabilize agricultural production as well as reduce the community’s vulnerability to water shortage. The core components of the required approach suitable for Jaisamand Lake Basin comprise the following:
- Soil and water conservation measures mainly in agricultural land such as check dams and vegetative barriers, stone bunds and terraces.
- Water harvesting structures (WHSs) such as anicuts and percolation tanks for efficient utilization of available rainwater.
- Alternate land uses for non arable lands such as afforestation and pasture development supported by rainwater conservation measures such as contour trenches and vegetative barriers.
- Water saving measures such as efficient irrigation practices.
- Promotion and strengthening of Self Help Groups (SHGs) as village institutions and capacity building of participating households/ beneficiaries with support from local Non-Governmental Organizations (NGOs), in order to ensure effective utilization, maintenance and sustainable operation of WHSs and soil and water conservation practices even after the withdrawal of support from NGO.
INITIATIVES IN GANGESHWAR MACRO-WATERSHED
Gangeshwar macro-watershed with a total area of 76 km2 is located in Jaisamand Lake Basin in Vallabhnagar and Dhariawad blocks of Udaipur District (Fig. 1). In spite of increased infrastructure development, the rural community in many remote and inaccessible parts of this area still remains far away from mainstream development. Initiatives were undertaken in this watershed in 2004 to introduce suitable adaptation and mitigation measures in the remote portions of the watershed in order to improve the livelihood of resource poor rural community.
The major source of water supply in the region is groundwater which occurs in the weathered zone and in fractures and other discontinuities present in hard lock. Using satellite data interpretation and limited field checks, the National Remote Sensing Agency, India, has prepared Groundwater Prospects Maps of Rajasthan. In these maps, the groundwater prospects of a region have been categorized under the following zones: good to moderate, moderate, moderate to poor, poor, and poor to nil. The groundwater prospects are generalized for the entire map coverage excluding the fracture/lineament zones where yield can be higher in hard rocks. Based on major fractures/lineaments clearly observed/inferred through satellite data, about 58% of the area of Gangeshwar macro-watershed falls under the category of ‘poor to nil’ groundwater prospect zone (Fig. 2). In view of severe water scarcity in this zone, adaptation and mitigation measures were taken up in an area of 9.21 km2 spread over 5 villages, viz., Borimagri, Kalalon-ki-Chatri, Harjibuj-ki-Bhagal, Surkhand and Samel, falling in the category of ‘poor to nil’ groundwater prospect zone. The total population of the study area is about 974 (as per survey carried out in 2004). The location of the actual study area within the macro-watershed is shown in Fig. 2. Table 2 gives the village-wise land use pattern in the study area.
Fig. 2 Groundwater prospects in Gangeshwar macro-watershed
Table 2. Village-wise land use pattern.
|Name of village||Total area (ha)*||Cultivated area (ha)||Common pasture land (ha)||Private pasture (ha)||Revenue land (ha)||Others (ha)|
|5. Kalalon ki Chatri||162||4||22||26||0||38||97||1|
*1 ha = 0.01 km2
To secure the livelihoods of the resource poor small and marginal farmers through suitable adaptation and mitigation measures, work was undertaken with the following specific objectives: to increase the water availability in a normal year; to increase the land productivity, and; to enhance capacity of the villagers/ beneficiaries to manage on their own the assets created by them. The details of the various measures taken up in the study area as well as the benefits achieved are described in subsequent sections.
A total of fifteen WHSs i.e. anicuts of different storage capacities were constructed (Fig. 3), out of which seven anicuts were constructed early during 2004-2005. The impact of these seven anicuts on wells within the zone of influence of each anicut has been monitored and the details are given in Table 3. The low cost structures were constructed on key drainage lines as well as on River Gomati. Photographs in Fig. 4 show the pre-monsoon and monsoon scenarios at the anicut site (WHS-2) in Village Samel.
Table 3. Water harvesting structures constructed in 2004-2005.
|Village||WHS code||Cost of work (Rs.*)||Community contribution (Rs.)||No. of beneficiaries/ families||No. of wells recharged||Storage capacity (m3)|
*Rupee (Rs.): Indian currency
Fig. 3 Drainage network in Gangeshwar macro-watershed and anicut locations in study area
Water harvesting structures have multiple beneficial effects, such as interception of water from the structure’s catchment and its storage for optimum utilization by local community. Such structures not only reduce the erosive effects of runoff but also prevent the gullies from further enlargement. The water retained on the upstream side can be used for both irrigation and domestic purposes. The stored water also helps in recharging the wells downstream.
As revealed by the data in Table 3, a total of 48 wells were recharged and 119 families benefited from the easy availability of groundwater. Figures 5 and 6 show the rainfall during monsoon season for the period 2004-2007 and the corresponding rise in water levels in Villages Surkhand and Samel during April/May 2004-2007. Irrespective of the varying rainfall each year during monsoon season, the wells show rise in water levels after the construction of WHS in the subsequent post-monsoon period compared to the scenario prior to WHS construction. The decrease in depth to water level (DTWL) post-WHS construction is visible even during the summer months of April/ May when the water levels are deepest. Due to the influence of anicuts, the wells have yielded sufficient water to enable cultivation of extra third season crop. The impact of low rainfall in monsoon 2005 is visible in Figs. 5-6 by the relatively larger DTWL during April/May 2006 in some of the wells. However, DTWL still remains shallower in post-WHS construction scenario compared to pre-WHS construction scenario. The farmers have also reported a decrease in water level ‘recovery time’ on pumping water from these wells.
Fig. 5 (a) Monthly rainfall at Village Surkhand (b) Water levels in April/May during 2004-2007
Fig. 6 (a) Monthly rainfall at Village Samel (b) Water levels in April/May during 2004-2007
The data in Table 4 show the impact on increase in irrigated area on account of groundwater recharge. Prior to construction of these structures the total irrigated area under the command of 39 existing wells (i.e. in 2004) was only 22.58 ha, which has now (upto Rabi 2007) increased to 38.59 ha which is an increase of about 16 ha (about 70%) in irrigated area. The increased irrigated area is mainly put under wheat crop, that too with improved variety, viz., Raj-3765.
Table 4. Increase in irrigated area due to groundwater recharge.
|WHS-code||No. of wells monitored during Rabi/ Zaid||No. of benefi-ciaries||Irrigated area (ha)||Increased irrigated area (ha)|
*Winter crop; **Third season crop
It is further evident from the data that due to these WHSs, there is a significant increase of area under zaid crop (third season crop) as well. During zaid 2007 an area of about 18.16 ha was put under green gram, lucerne, vegetables, small millets and other fodder crops compared to only 0.42 ha under zaid crop prior to WHS construction in 2004. Construction of these structures provided an opportunity to the villagers to earn an additional income e.g. construction of one structure on average generated wages of Rs. 93,000.00.
Water harvesting structures aided by good monsoon rainfall in 2004 and 2006 increased the flow duration of River Gomati by 2-3 months. The river also recharged 26 wells and provided sufficient water to 75 families for drinking, and irrigation to 31 ha of agricultural land. In addition to the main crops, farmers were able to cultivate vegetables and earned an additional income of Rs. 10,000 from the increased production.
SOIL AND WATER CONSERVATION
The upper reaches of the entire study area (refer Fig. 3) were treated by Loose Stone Checkdams (LSCD) for in-situ soil and water conservation.
Fig. 7 Loose stone checkdam at Village Harjibhuj ki Bhagal
These LSCDs were planned and constructed as per specific site conditions and slope, in particular. Horizontal interval between two structures was kept as 30 m. A total of 747 LSCDs were constructed in all the five villages. Photographs in Fig. 7 show the pre- and post-LSCD construction scenes. As per estimates, each structure on an average conserved/ deposited about 12 tons of sediments, which is about 8900 tons for all the 747 LSCDs (village-wise details are given in Table 5).
Table 5. LSCD constructed during 2004 to 2007.
|Village||No. of beneficiaries||No. of LSCD||Treated area (ha)||Cost of work (Rs.)||Community contribution (Rs.)|
|4. Harjibuj ki Bhagal||27||85||50||85,654.00||19,765.00|
Loose stone checkdams protect the gully beds by retarding the runoff, redistributing it, increasing its infiltration, encourage silting and improve the soil moisture regime for establishing grass and other vegetative cover. In the treated area, only about 10% LSCDs have completely been filled up with sediments. The whole area is now almost stabilized by vegetative cover (trees, shrubs and grasses) and hardly any erosion is there. Further, out of 747 LSCDs only about 70 are damaged due to heavy rainfall and destroyed by cattle during 2004-2007, which is negligible. The construction of these structures helped the villagers to earn an additional income e.g. construction of 604 LSCDs during the period 2004-2005 generated wages of Rs. 346,514.
On surveying the treated area at the end of 2007, it was felt that owing to silting up of land on the upstream side, where necessary, the structures should be raised or upgraded. Further, the silted up area should be planted with appropriate plant species. Under the existing situations/ topography, it is recommended to keep average horizontal interval of about 20-25 m against the existing 30 m in order to make them more safe and effective. Further it is also suggested to combine these LSCDs with vegetative barriers/ checks to make them more stable and effective.
TREATMENT OF ARABLE LANDS
Construction of stone bunds or barriers, or Puerto Rico Terraces (PRTs), is an adaptable indigenous soil and water conservation measure on moderately sloping arable lands where the depth of soil is a limiting factor for cultivation of crops. By adopting this practice, one can put land with a limited depth of soil safely under cultivation, check soil erosion and reduce runoff, thereby increasing infiltration. PRTs were constructed on lands that existed on the sides of the valleys and in lower reaches, while ‘peripheral bunds’ mostly of stone were constructed on lands situated along the banks of major drainage lines and streams.
These structures were constructed only where treatment was mostly needed to control and/or check soil erosion and increase in-situ moisture conservation in the field to boost productivity. This intervention, initially, was taken up in Village Samel where approximately 9.5 ha amongst 26 families are covered. The participating households contributed upto 50% towards the cost of constructing these structures. Subsequently, similar treatment was also taken up in Village Bodimagri covering nearly 12 ha of land between 43 families and in Village Surkhand in approximately 25 ha of land distributed amongst 28 families.
Good and effectively managed arable lands ensure not only food security but also other livelihood solutions, as well as reduce vulnerability and ill effects of drought in semi-arid regions. The benefits were visible in terms of an increase in cultivated area by 56% after treatment and enhanced farm productivity. The damaged or breached PRT were repaired by the village community. The SHG leaders in respective locations took the responsibility to ensure that the repair works were carried out in earnest, which is an example of how the SHGs, as village institutions, can take on leadership role and functions and responsibility for the maintenance of assets created in the watershed.
In the semi-arid water scarce region of Gangeshwar macro-watershed, large diameter dug wells are in use and water from the wells is lifted by different lifting devices. Renovation of these wells helps to prevent the walls of the well from collapsing. A total of 32 of open dug wells were renovated by lining the inside walls of the well in stone masonry and construction and/or repair of elevated platform (Table 6). This intervention stops an asset of the farmer from being further damaged or lost completely. In some places the lining of irrigation channels too was carried out.
Table 6. Well renovation during 2004 to 2007
|Village||No. of wells||No. of beneficiaries||Cost of work (Rs.)||Community contribution (Rs.)||Remarks|
|1. Samel||7||27||192,709.00||116,991.00||Shared wells|
|2. Surkhand||8||20||204,482.00||125,488.00||Shared wells|
|3. Harjibuj ki Bhagal||5||13||89,571.00||57,471.00||Shared wells|
|4. Bodimagri||10||25||256,048.00||157,457.00||Shared wells|
|5. Kalalon ki Chatri||2||5||78,900.00||63,444.00||Shared wells|
Lining of irrigation channels contributes to ‘water saved’ from losses due to percolation. Water thus saved can contribute to an increase in area cultivated and/or increased water availability for ‘critical irrigation’ in both Rabi as well as Kharif cropping season (when monsoon fails). Further, the lining of channels also contributed to a reduction in time spent on crop irrigation.
HUMAN AND INSTITUTIONAL RESOURCE DEVELOPMENT
Training programs on various aspects of water harvesting and soil and water conservation measures for capacity enhancement of the participating village community were organized with help and support from the local institution ‘Sahyog Sansthan’ which has developed a good network with the villagers. Trainings were conducted to improve and strengthen their management skills and systems in place. ‘Field days’ were organized for the trainees as well as the participating farmers from within the watershed and from the neighbouring villages. In all 16 SHGs have been promoted and strengthened, and are functioning in the five villages covered under the watershed.
TOWARDS A SUSTAINABLE LIVELIHOOD
The protection and sustainable use of water resources plays a decisive role for the future of humankind. In the water-scarce Jaisamand Lake Basin, water availability has a direct impact on livelihood security such as food availability, animal husbandry and forest produce. The adaptation and mitigation techniques in the basin have facilitated easy access and availability of water for drinking and irrigation purposes. The increased availability of water in each village of the study area has led to increasing interest of the farmers in agricultural activity, increase in crop production and visible improvement in health of women and children with more time for social activities due to reduction in time spent on fetching water on foot over long distances. Thus, the adaptation and mitigation measures have not only helped in increasing the water availability but also in enhancing the productivity of food grain and fodder crops, allowing income generation thereby reducing poverty and increasing the resilience of the local community in successfully coping with the water scarcity.
Water is an indispensable prerequisite to improve quality of life and achieve sustainable development. The adaptation and mitigation measures implemented in the water scarce semi-arid area with the participation of villagers have facilitated the recharge of groundwater and have benefited the poor rural community in terms of enhanced crop production, availability of irrigation water even during low monsoon rainfall, and cultivation of third crop, all of which has given a boost to the earning capacity of the rural community as a whole. The measures taken up have also reduced soil erosion and aided the growth of vegetative cover. In addition, capacity building of village communities has ensured effective utilization, maintenance and sustainable operation of water harvesting structures and soil and water conservation practices by the participating rural community so that the benefits continue to build up over the years.
The authors are thankful to the dedicated staff of ‘Sahyog Sansthan’, Udaipur, for their ready help and cooperation during the course of the study. The authors also acknowledge the support by Mr Rajan Vatsa, Scientist, National Institute of Hydrology, Roorkee, in the study. Both the village community and Wells for India – India Liaison Office, Udaipur, contributed towards the construction cost of water harvesting structures in the study area.
GOR (2004) Statistical handbook of Udaipur District. Government of Rajasthan (GOR), Jaipur, India.
GOR (2005) State Water Policy. Government of Rajasthan (GOR), Jaipur, India.
Narain, P., Khan, M.A. and Singh, G. (2005) Potential for water conservation and harvesting against drought in Rajasthan, India. Working paper 104 (Drought Series: Paper 7), International Water Management Institute, Colombo, Sri Lanka.
SRSAC (1999) Ground Water Atlas of Rajasthan. World Bank (IDA) Aided Project. State Remote Sensing Application Centre (SRSAC), Jodhpur in collaboration with Ground Water Department, Jodhpur, India.[/vc_column_text][/vc_column][/vc_row]