According to the data released by the Food and Agricultural Organisation’s AQUASTAT in 2010, at 250 billion m³ per year, India is one of the countries that uses groundwater the most. As high as 80 percent of its water is used for irrigation of which 65 percent is groundwater.
This paper Bi-decadal groundwater level trends in a semi-arid south Indian region: Declines, causes and management published in the Journal of Hydrology: Regional Studies says that the large-scale groundwater withdrawal is due to the increase in number of irrigation wells with diesel or electric pumps in the country. There has been a 130-fold rise in irrigation wells--from 0.15 million in 1960 to nearly 20 million by 2000. This over-extraction of groundwater is leading to extreme groundwater depletion and many other related environmental problems in many parts of the country.
Although states like Punjab, Haryana and Telangana have high levels of groundwater use, the aquifers in these regions are different. The deep alluvial aquifers found in Punjab and Haryana have more water-holding capacity than those in Telangana. So while the declining water table may not affect the water availability in Punjab, at least not in the short run, the situation is different in Telangana due to the shallow nature of the aquifers. One of the reasons for the groundwater depletion in Punjab and Telangana is speculated to be the free electricity provided to the farmers. No studies, however, have been done to verify this.
The former state of Andhra Pradesh, divided into two states namely Telangana and Andhra Pradesh on June 2, 2014, had the free electricity policy for farmers implemented in May 2004. Although it has been argued that free electricity has triggered extensive well drilling in Telangana, there is very little evidence to support this claim.
This article presents the findings of a study done on three districts in Telangana--Rangareddy, Medak and Nalgonda--spanning 22 years that examined the correlation between free electricity provision in Telangana and its implications on the groundwater security in the state.
The study was aimed at:
- Analysing the long-term (1990-2012) trends in the groundwater levels in the districts
- Identifying whether the changes in the groundwater levels were due to the natural variability in the rainfall or any other factors such as power subsidy
- Discussing possible policy mechanisms for sustainable use of groundwater
The study findings
The study was done on one-third of the wells in the three districts (mentioned above) that reported a decline in the groundwater levels due to the increase in the area irrigated by groundwater.
It was found that the area irrigated by groundwater has increased by 110 percent in a 22-year-period from 1990 to 2012 which includes 90 percent of Rangareddy and Medak districts and 65 percent of the Nalgonda district. This is mainly due to a 30-fold increase in the use of tube wells for irrigation purpose and an accompanying decrease in the use of water from the reservoirs and open wells. Reliability is a major factor contributing to the popularity of drilled wells in the region.
Free electricity, which the state began to provide in 2004 is one of the important reasons for this steady increase in groundwater-irrigated areas. More than 98 percent of the tube wells in the study area were found to use electric pumps as of 2006-2007. Telangana state provides five to seven hours of daily free electricity for pumping. However, this electricity is often very unreliable and low in quality. Untimely and low quality electricity causes wasteful groundwater extraction and use, high electricity consumption and increased pump repair costs--a lose-lose situation for both farmers and electricity boards. Two to three hours of uninterrupted quality power supply could help reduce the wastage of electricity and reduce groundwater withdrawals.
Free electricity has been found to have benefited medium and large-scale farming more although it was meant to help small-holder farmers. Ninety percent of small and marginal farmers in the state do not own an irrigation well and their financial capacity to dig a new well with a pump is limited. This is because drilled wells become unproductive in a short span of time and digging deeper and frequently is not possible because of the financial limitations of the small farmers.
Climate change has been predicted to increase the intensity of rainfall in the future. The paper argues that in the case of Telangana, this is not good news for groundwater recharge because of the poor water retention capacity of its aquifers resulting in runoffs. This will further deplete the groundwater in the state. Faulty cropping patterns, such as an increase in irrigation-intensive crops like paddy, are another reason for groundwater depletion.
Policy mechanisms for regulation of groundwater use
Various regulatory Acts and guidelines have been developed for proper management of surface and groundwater resources in Telangana. The Andhra Pradesh Water, Land and Trees Act was enacted in 2002 for the integrated management of surface and groundwater resources. This Act needs farmers to register the existing borewells and receive permission to dig new irrigation tube wells. Although the Act has been successful in registering existing borewells, few farmers have complied with the permit requirement for drilling new tube wells. Under this Act, only 2500 wells were given permission in 2005-06 but the Transmission Corporation of Andhra Pradesh Limited reported 66,000 individual agricultural electrical service connections during this time for drilling tube wells indicating that more number of tube wells were actually drilled during this time.
The paper argues for a policy to restrict the number of tube wells and better coordination between the state electricity board and the agency granting permission for drilling of new wells. Deeper drilling has also led to a number of groundwater quality problems with the three districts under study having excessive fluoride and nitrate levels in groundwater.
The paper argues that the study findings highlight the need for:
- A careful consideration of the reform in the existing power subsidy policy
- A policy to restrict the expansion of tube wells
- Water management focusing on the reduction in demand for groundwater by change in cropping patterns and reducing water use through conservation measures such as promotion of drip irrigation
- Designing further studies to verify the impact of power subsidy with groundwater declines for Telangana
- Careful and detailed region-specific water balance and modelling studies to improve sustainable water use and encourage agricultural sustainability
A copy of the paper can be downloaded from below: