Agriculture contributes to 18 per cent of India’s Growth Domestic Product
Agriculture contributes to 18 per cent of India’s Growth Domestic Product (GDP) and together with other allied sectors provides livelihood to two-thirds of its population. Rains are the main source of water for the 60% of arable lands. Unpredictable rainfall pattern and increasing droughts are greatly impacting the agriculture and meet drinking water needs. India receives 80% of the rainfall during 100-120 days of monsoon (Kumar, Singh et al. 2005). Such high-intensity rainfall in a short period leading to huge runoff to downstream. Effective Rainwater Harvesting (RWH) combined with the integrated and adaptive watershed management offers an optimal solution to capture and store this precious quantity of water that could be utilized for recharging shallow groundwater aquifers thereby improving the irrigation and drinking water needs, and ecosystem, at the same time catalyzing overall rural development. This paper analyses the opportunities, challenges, and limitations of RWH as a contributory factor for effective watershed management in the rainfed areas of India and offers suggested improvements and change in policies in relation to the planning and development of watersheds. It is concluded that an integrated approach supported by sound hydrological analysis, and sustained monitoring and control results in successful watershed projects.
Keywords: Rainwater harvesting, watershed management, groundwater, agricultural and rural development.
A sacred prayer from ancient Rig Veda, the oldest sacred scripture in Sanskrit proclaims ‘Apo Janayatha Chanaha’ which translates as ‘O Water, you are the source of our lives’. It is no wonder civilizations flourished along rivers and watersheds of India, where populations adapted to careful harvesting, storing, and managing rainfall, runoffs and stream flows for centuries. In the southern part of India over 1500 years ago, the kingdoms of Cheras, Cholas and Pandyas constructed thousands of irrigations tanks. The Grand Anicut across Cauvery river built in the 2nd Century AD by Cholas, indicate that watershed development is deeply rooted in social and cultural structures of the country. India’s economy is significantly dependent on Monsoon, the seasonal annual rains to such extent that framed a famous cliché ‘The Indian Budget is a gamble on Monsoon’. Rainfed areas in India are classified of receiving more than 750 mm of rain per year, comprised of arid and semi-arid ecosystems stretching from the western state of Gujarat to Eastern Madhya Pradesh and from Rajasthan to the Southern tip of the country. India is positioned first among the rainfed agricultural countries of the world in terms or the area and value of produce. Poverty is concentrated in the rainfed regions due to population pressure on agricultural lands. The climate in India’s rainfed regions is characterized by complex climatic deficiencies, manifested as water scarcity for crop production. The climate is largely semi-arid and dry sub-humid with a short and occasionally intense wet season followed by long dry season. Rainfall is highly unreliable, both in time and space, with strong risks of dry spells at critical growth stages even during good rainfall years (Source: Resurgent India).
The major portion of the annual rainfall is received in around 100 hours of heavy monsoonal downpour, providing short-time for natural recharge of the aquifers due to rapid runoff. As more deforestation is occurring in the catchments, the detaining time is reduced resulting in increased runoff. The solution lies in harvesting the rainwater by capturing, storing, and recharging it through developing several micro watershed systems managed by the participatory approach. Rainwater harvesting stores the monsoon runoff that percolates to groundwater tables (Keller, Sakthivadivel et al. 2000). Aggarwal (2000) points out that every village in India can meet their water demands for groundwater recharging, irrigation, drinking water requirements, and improvement of ecosystems if this substantial runoff is effectively captured.
The trends during the 1990s show that there has been a progressive shift of budgetary allocations from irrigation development to RWH (Shah 2013). Methods to recharge aquifers, including RWH (often referred as artificial recharge), have become so widespread in India over the last two to three decades that it is now referred to as ‘a groundwater movement’ or ‘artificial recharge movement’ (Sakthivadivel, 2007).
A large rural population of India are extremely poor mainly reliant on rain-fed agriculture for their livelihood. Extreme fluctuations in rainfall pattern severely impact their lives. Water resources development is the main component of rural development in India. Effective utilization of natural resources is the key to overcome poverty. Maximizing the use of the available rain, surface, and groundwater is most essential to achieve this objective. Detaining and exploiting the maximum possible rainwater have therefore become the main strategy that points to micro-watershed development as the natural choice.
A Government of India Policy statement emphasizes that “integrated and holistic development of rainfed areas will be promoted by conservation of rainwater by vegetative measures on watershed basis and augmentation of biomass production through agro- and farm-forestry with the involvement of the watershed community. All spatial components of a watershed, ie, arable land, non-arable land and drainage lines will be treated as one geo-hydrological entity. Management of grazing lands will receive greater attention for augmenting availability of animal feed and fodder. A long-term perspective plan for sustainable rainfed agriculture through a watershed approach will be vigorously pursued for development of two-thirds of India’s cropped area which is dependent on rains” (Government of India 2000b).
A comprehensive report on watershed development programs submitted to the Government of India in 2006 by the Parthasarathy Committee argues that the rainfed parts of Indian Agriculture have been the weakest though they contain the highest unutilized potential for growth. The report further reiterates that even by the most optimistic scenario of irrigation development, nearly 40% of the national food demand in 2020 will have to be met by increasing the rainfed agriculture that demands intensive watershed development in these regions (Source: indiawaterportal.org).
RAINWATER HARVESTING (RWH):
RWH is a process for capturing and storing rainwater for efficient utilization and conservation controlling its runoff, evaporation, and the seepage (Kumar et al.) that encompasses methods to induce, collect, conserve, and store runoff from various sources and purposes, by linking a runoff-producing area with a separate runoff-receiving area (Boers and Benasher, 1982). Some of the key benefits of RWH are highlighted as
• Improved water availability
• Reduction of groundwater decline and recharging
• Environment-friendly and improves the watershed ecosystem
• Groundwater quality improvement through dilution of fluoride, nitrate, and salinity
• Prevention of soil erosion, silting and flooding
• Socio-economic benefits achieved by rural development through improved agriculture and non-land related initiatives
RWH methodology has three common characteristics (Boers and Benasher, 1982)
1. It involves small-scale capture of rainwater and does not feature river water detention in large reservoirs or groundwater mining.
2. It is relevant in arid and semi-arid regions where runoff is intermittent due to intermittent and highly variable rain pattern making them susceptible to drought and floods.
3. It is comparatively small scale relative to the catchment area, storage volume, and capital investment, and hence viable for micro-watershed management.
Fig 1: Schematic representation of a simple RWH system for groundwater recharge
(Glendenning et al.)
RWH using runoff conservation structures (gully plug, rockfill dams, check dam, farm ponds and bench trenching) is basically intended to slow or stop the running water (contour trenching and subsurface dams) and to infiltrate (percolation tank) into the underground. (Raju et al.).
Since RWH structure capacities are smaller, they respond faster to detain runoff water that percolates and replenish groundwater table. The groundwater, in turn, is used for irrigation and domestic purposes through dug and tube wells. Rainwater harvesting also tends to lead to increased crop production intensities and greater crop yield, because rises in the water table mean better accessibility and yields of groundwater (Keller, Sakthivadivel et al. 2000).
A World Bank initiated water sector study (Briscoe and Malik, 2006) noted that community “rainwater harvesting” as the solution, everywhere and for almost all problems for India’s water woes.
WATERSHED DEVELOPMENT POLICIES AND DESIGN APPROACH:
Watershed Management is an integrated holistic approach to developing, conserving, regenerating, and optimized usage of natural and human habitats within a shared ecosystem comprised of geological, hydrological, and ecological components located in a common catchment/drainage system. Watershed shall be understood as dynamic systems characterized by diverse interactions and spatial relations between humans and the environment that manifest as mosaics of different land-use systems. The socio-economic, cultural and environmental relationships flow and conflicts between the upper and lower parts of a watershed are called upstream-downstream linkages. Consideration of these linkages is one of the key principles of watershed management (Definition: FAO.org.).
The watershed programs in the country are undertaken with multiple objectives ranging from areas to conservation of the resource base and improvement of the productivity of agriculture. Mitigating adverse impacts of droughts and resource degradation will contribute to reducing production risk and protecting livelihoods. Conservation of the resource base will contribute to sustainable productivity growth in agriculture, while the latter will improve the incomes of the poor and contribute to poverty reduction.
A document ‘Vision for Integrated Water Resources Development and Management’ released by the Ministry of Water Resources, Government of India (GOI) stressed the need for rainwater harvesting as a reliable method in preventing soil erosion, providing sustainable irrigation and mitigating the drinking water shortage. The action plan set to accomplish rainwater harvesting is to support non- government efforts in rainwater harvesting both financially and technically (GOI 2003). Similar thrust has been given by various state governments in their respective ‘Vision 2020’ documents implying that watershed programs would receive high priority for conserving rainwater, preventing soil erosion and overcoming the vulnerability of the poor in the rainfed areas. These policies clearly demonstrate the commitment of national and state governments for the development of rainfed areas through watershed management.
In recent years, the watershed programs have increasingly focused on poverty. There has been a shift from assessing the impact of watershed management on the regeneration of the natural resource base, health of the environment and agricultural productivity to enhance the overall impacts on poverty and livelihood security. Enhancing people’s livelihoods, reduction of poverty and sustainability are being recognized as being the main objectives of watershed programs. (SAT eJournal | ejournal.icrisat.org August 2006 | Volume 2 | Issue 1)
Location specificity is an extremely important aspect of watershed planning since a population-resource interaction generates varied situations under heterogeneous environments, which were difficult to simulate prioritization. However, watershed treatments impact the income structure and stabilize income flows by reducing the overt fluctuations and making a positive impact on income distribution. Multilevel stakeholder participation and scientific input are the two most important components of watershed planning that enhance impacts (Deshpande and Reddy (1991)).
Rigorous water assessment needs to be performed prior to the water harvesting structures installation. The assessments should be carried out considering the volumes of water retained in any existing structures in relation to available water resources and minimum flow requirements before new structures are installed. It might be possible that the existing structures considered as having an optimal design related to the density of RWH structures, might have been ‘over-engineered’, although the available water resources might have decreased through agricultural intensification and catchments degradation. (Calder et al.).
It is important to apply a cross-disciplinary approach for data collection and analysis to successful management of water resources on an individual watershed basis. Water quality and quantity assessments based on traditional inputs combined with biological, botanical, geomorphology, and anthropological subjects like economical evaluation are important decision support factors for deriving design considerations of watersheds (David et al.)
Three new management/dissemination tools for the planning and development of interventions involving RWH focussed watersheds are (Calder et al.)
• The web-based geographical information systems exploratory, climate land assessment and impact management tool dissemination tool for disseminating to policymakers and non-specialist stakeholders the downstream impacts of watershed interventions
• The ‘Quadrant’ approach to ensuring that the sustainability criteria are met
• Bayesian networks to investigate the biophysical and societal impacts of interventions.
RIDGE TO VALLEY APPROACH:
Ridge to Valley approach is a desirable option to optimize overall development to maximize benefits from the Watershed. The treatment measures are initiated from the highest level, progressively moving downward, where the upper catchment areas including forest areas and upper reach ridges where lands of marginal farmers that are located. This results in a reduction in velocity of water, soil conservation and prevention of silt deposition in water harvesting structures on the downstream sites allowing better management. The method contributes to improved efficacy, economic stability and durability of soil and water conservation structures. (Baif.org.)
CATCHMENT ASSESSMENT AND PLANNING:
Hydrogeological modelling is a useful tool in investigating the multi-scalar impacts of watershed development that supports planning at various institution levels. SWAT (Soil and Water Assessment Tool) is one such model that is being integrated into the Government of India’s existing planning methodology under the Integrated Watershed Management Program (IWMP). The GOI guidelines provide 13 different parameters and Geographic Information Systems (GIS) that are to be used to identify and prioritise watershed development. The guidelines emphasize the importance of hydrology in the selection process. However, socio-economic goals take precedence in the selection process, in most of the cases discounting the potential downstream externalities. A socio- hydrological dynamic (SD) modelling that provides a framework to integrate hydrological and socio-economic and policy systems in a holistic approach proposed by Adamowski et al. would probably be a futuristic solution to combinedly address the stated issue.
In many cases, the lack of accessible hydrological data is the main concern to provide the right inputs into the selection and planning of watershed development. Due to the high variability of recharge rates in time and space from individual RWH structures makes their assessment and monitoring complex. Hydrological models are practical solutions to support watershed development, in terms of site selection, downstream impacts assessment for investments in soil and water conservation interventions, research studies etc. Increased asses to remote sensed digital data through satellites, availability of advanced open-source software and decreased computing costs have recently fuelled increased use of hydrological modelling in India. However, the key challenge in using advanced modelling systems lies in non-availability of data in many watersheds specifically the stream flow gauging, makes accurate calibration and validation of the models almost difficult. Besides, the modelling in rainfed areas of India is challenging due to the variability of the climatic conditions. Additionally, the surface and groundwater interactions that are most necessary to represent RWH hydrological processes, are limited to many available models.
Fig 3. SWAT- Hydrological Modelling tool (source: https://www.slideshare.net)
STRATEGIES FOR UPSTREAM AND DOWNSTREAM TRADE-OFFS:
Watershed management strategies through RWH for rainfed agriculture would result in trade-offs with downstream water use and ecosystems. However, selecting the right management strategies and watershed designs can minimize these trade-offs. The increased productivity manifests in improved water utilization where the yields from rainfed agriculture are low. Water productivity improvement results in a vapour shift, which means an increase in productive green water flow without affecting the blue water flow due to the reduction in non-productive runoffs. Hence, investments in rainfed agriculture by means of in-situ or ex-situ RWH causes comparative improvement in water productivity. Capturing blue water close to the source through in-situ water harvesting increases green water resources. This strategy reduces evaporation loses of blue water which otherwise would have been used for irrigation downstream, at the same time limiting erosion. Through an integrated approach, the trade-offs can be best managed for the benefits of both upstream and downstream stakeholders
(Carlberg, L et al).
BENEFICIAL IMPACTS OF RWH FOCUSSED WATERSHED PROJECTS:
• Beneficial impacts are categorized as an increase in cropping intensity, change in cropping patterns, crop productivity improvement and increase in underground recharge because of conservation measures, reduction in soil and run-off losses with lesser siltation effect and reduction n sedimentation at the watershed level. These projects have also generated employment and increased family incomes through the diversified farming system such as livestock development, dryland horticulture and household production activities.
• Micro-watershed rehabilitation in India could make significant contributions to reversing environmental degradation, largely through improved recharge of groundwater and permit a quantum shift in sustainable agricultural productivity in the lower slopes of watersheds. (Government of India 2001c)
• Kerr et al. (2002) noted that the impact of watershed development programs in the rainfed areas that focussed on the participatory approach was successful. Also, participatory watersheds performed better than the more technocratic, top-down counterparts, and the programs with a combination of people’s participation and sound technical input performed best.
• Results from a meta-analysis comprising 310 watersheds in India revealed that the mean benefit-cost ratio of watershed programs in the country was quite modest at 2.14 (Joshi et al. 2000). The average internal rate of return was 22%, which is comparable with many rural developmental programs. The watershed programs generated more employment opportunities, augmented irrigated area and cropping intensity and conserved soil and water resources. The study added that performance of watershed programs was best in regions with a rainfall ranging between 700 and 1000 mm, jointly implemented by state and central governments, targeted in low- and medium-income regions, and had effective people’s participation.
• Farrington et al. (1999) also provided an overview of the recorded impact of watershed development programs in the country. Results indicate that successful projects have in fact reduced rainwater runoff and recharged groundwater and surface water aquifers, improved drinking water supply, increased the irrigated area, changed cropping patterns, crop intensity and agricultural productivity, increased availability of fuel and fodder, improved soil fertility and changed the composition of livestock.
ISSUES AND CHALLENGES:
• The main disadvantage of RWH watersheds is that open storages are often subject to high evaporation losses, due to a high surface area to volume ratios (Neumann, MacDonald et
• Quantifying the overall impact of RWH in a catchment is important because it can cause unintended impacts such as inequitable sharing of water between upstream and downstream users (Batchelor, Singh et al. 2002).
• There are only a few published studies that have accurately quantified the nature and magnitude of upstream-downstream conflicts in India, with most being mainly site-specific and descriptive (Kumar, Ghosh et al. 2006; Sakthivadivel 2008). Additionally, the studies relate mainly to RWH storage, but there is a lack of research on recharge or streamflow impacts.
• Despite the long history of the watershed development programs, there are no systematic and largescale impact assessment studies on the performance of watershed programs. Individual scholars, NGOs, and international agencies undertook some studies largely on a project basis. Otherwise, conclusions are derived from qualitative assessments and impressions.
• Farmer acceptance of water harvesting techniques has been limited, due to the high costs of implementation and higher short-term risk due to the necessity of additional inputs, cash, and labour. Water harvesting initiatives frequently suffer from lack of hydrological data and insufficient attention and important social and economic considerations during the planning stages, and the absence of a long-term government strategy for ensuring sustainability of interventions (Rosegrant et al. (2002)
• Several reasons can be identified for lack of significant impact of watershed programs such as complexity of the evaluation, delayed ecological effects and non-tangible project effects. Demand-oriented projects were site-specific and difficult to replicate. (Rosegrant et al. (2002))
• Proper indicators and evaluation methods are not available to assess the tangible and non-tangible economic, social, and sustainability impacts of the programs.
• In many cases, an increase in agricultural production did not last for more than two years. Structures were abandoned because of lack of maintenance and there was no mechanism for looking after common lands. Projects have failed to generate sustainability because of the failure of Government agencies to involve people ((Government of India 2001c)
• The impact of the projects on poverty alleviation and the long-term sustainability of project results were, however, less clear. Although some projects did seem to have paid attention to the needs of the landless and poor, their impact on poverty reduction was not assessed.
• Lack of appropriate institutional support is impending in tapping potential benefits of the watershed programs. The isolated and piecemeal approach to watershed development has not also been consistent with large-scale technology exchange and dissemination Farrington et al. (1999)
• Many government-sponsored approaches were expanded rapidly, but often lacked the local ownership and group coherence necessary for sustainable management of the common pool components of watersheds. If micro-watershed programs are to be participatory and rapidly replicable, it is important to identify enabling conditions for scaling up and out (Farrington and Lobo 1997)
• A key challenge in evaluating the successes and failures of watershed projects is the lack of baseline data (Upadhyay, K)
• Legacies of central planning versus participatory approach.
• Lack of sustainable funds is another major reason for the long-term consolidation and replication of watershed management.
KEY SHORTCOMINGS OF WATERSHED PROJECTS IN INDIA:
Kumar et al. identify six critical shortcomings in RWH focussed watershed development efforts in India
• Lack of emphasis on the local potential for supply in relation to the demand. In many cases, the demand far exceeds the local supply.
• Inaccurate economic evaluation due to the complexities; mainly due to lack of scientific information on the water inflow, runoff collection and storage efficiency, beneficiaries, calculation of incremental benefits generated, and scale considerations. While the scale of the watershed increases, the marginal benefits from RWH at basin level reduces at the same time the marginal costs increases.
• Trade-offs between maximizing the hydrological benefits versus improving cost benefits. In many cases, there is a lack of a balanced approach.
• Disparities in demand between the upstream and downstream catchments, leading to trade-offs between upstream RWH and optimised basin wide benefits.
• Water harvesting often divides the hydrological benefits rather than augmenting them.
• Poor integration between surface and groundwater due to non-inclusion of natural recharging that in turn results in the reduction of artificial recharge.
The following additional deficiencies are also observed:
• Many projects ignore the hydrologic boundaries of watersheds. Watersheds are treated as stand-alone units discounting the interconnectivity between many watersheds.
• Interventions are designed and constructed without proper assessment of the hydrogeological characteristics of the watershed.
• Qualitative and quantitative evaluation processes are limited or not implemented.
• Lack of long-term socio-economical and ecosystem sustainability.
• Mostly supply side focussed without much importance given to the demand management.
PATH FORWARD RECOMMENDATIONS:
• A major policy shift to include the entire drainage area that covers sub-areas of the basin, to effectively address equity and externality issues. A critical analysis must be conducted on how RWH reacts to the hydrology of the watershed and impacts the water balance perspective of the entire basin.
• The concept ‘save the water where it drops’ promulgated by Government of India has to consider the overall impact on ecosystems through effective feedback mechanism from various stakeholders like agriculture, forestry, environmental, watershed development etc.
• It is important to emphasise on equity and societal issues, through socio-economic analyses of the watershed with an integrated approach for equitable sharing of benefits. The benefits should not be limited only to agricultural returns but also focus on improved access to drinking water, stakeholder empowerment and non-land-based employment opportunities.
• Comprehensive analysis of watershed in respect to water use and water users by using effective modelling systems must be incorporated in the Integrated Water Management plans. However primarily, it is required to establish a robust data collection method to ensure a reliable database availability.
• Watershed development should not be just RWH focussed as is the case now. India’s heavy reliance on groundwater necessitates through examination of RWH impacts on groundwater replenishment. Equitable and sustainable synergizing of both surface and groundwater are important. The entailed results should be established and conveyed to stakeholders to ensure the success of the watershed programs, particularly making them demand focussed.
• As in many Federal Countries, the responsibility for implementation watershed development in India falls under the purview of the State Governments. However, policies and procedures are framed by the Central Government. There is a gap in integration between the Central and State Governments and between different States. It is of foremost importance to establish a framework that offers a clear mode of cooperation and facilitate integration between them.
• Land ownership among women is very few in India, limiting their participation as decision making stakeholders in watershed development programs. A shift change needs to occur to empower them being treated as a disadvantaged group, to a point where they become integral contributory partners in watershed development programs.
• It is important to include traditional knowledge.
• Establish mechanisms to ensure long-term sustainability and management of watershed structures by effective monitoring and control processes involving local stakeholders.
• Create a benchmark to evaluate the failures and successes of watershed projects.
Rain Water Harvesting has emerged as the centrepiece of the watershed program for rural development in India, providing credible solutions to many issues faced by the rainfed areas in the country. However, the challenge lies in the economic evaluation of the RWH systems due to complexities in quantifying the hydrological impacts and various socio-economic benefits. An equitable trade-off between upstream and downstream water use and managing externalities assumes paramount importance. There is a great progress in hydrological modelling due to easy availability and access to new advanced technologies. However, the accuracy of the models turns out to be unreliable due to non-availability of adequate input data. Several positive contributions of RWH focussed participative integrated watershed development programs have been established. At the same time, many shortcomings are identified that must be addressed to ensure the long-term sustainability of these programs. An emphasis is placed on participatory equitable approach, particularly to include women as contributory stakeholders. It is concluded that to derive maximum benefits, systematic research and development focussing on physical, hydrological, socio-economical, environmental and institutional aspects are essential.