With the growing population in India, the demand for water is increasing exponentially. Water is in demand not just for individual consumption but in various sectors like agriculture, manufacturing, construction etc. While the demand is growing at a rapid pace, the availability of water has declined sharply in the past five decades. Reports say that the there is high amount of inequality in the demand and availability of water in the rural and urban areas. While the demand is 135 liters per capita in the rural areas, it is about 40 liters per capita in rural areas. This sharp demand for water has also been the cause of inter and intra-state disputes in the country. The problem of water is so multidimensional in nature, with no specific single cause, that a multipronged strategy will be required to solve it. Better water management techniques, awareness campaigns, strategies of reducing water wastage and increasing the availability of water will all have to explored.
Agriculture Based Consumption
So what are the water needs in various sectors? Agricultural irrigation consumes the maximum amount of water and in the coming years we would see an increase in the consumption of water by the energy sector.
While we assume that this water comes from entirely from the rivers, data says that only one-third of the river water is usable. The remaining water comes from borewells which are dug very deep in rain shadow areas. So where does this borewell water come from?
We get this water from aquifers which are of two types namely: confined and unconfined. Unconfined aquifers are the most accessible and located beneath the ground. These aquifers are formed by the water that seeps in from the ground surface above. Confined aquifers are deep inside and it is difficult to permeate into them. In some countries where water is really scarce, people have started consuming confined aquifer water which has taken thousands of years to build up.
The groundwater we use for daily is from unconfined aquifers and they do not have a protective mechanism. Digging these borewells uses up a large part of unconfined aquifers and the worst part is that these aquifers can be polluted easily and hence extensive use of fertilizers can be extremely detrimental. So a 360 degree view of the problem is needed to be able to solve this. Solutions cannot be just at the individual level but also bigger policy decisions are needed. For instance, while as citizens we can take measures to regulate our daily water usage, construction of large number of dams has to be rethought. While dams made good sense before 50 years, now they make very little economic sense. Several scientific studies, including one by the United Nations Environment Programme in 2001, emphasize that dams have two main adverse effects on rivers. First, dams alter the chemical content and temperature of water. Water stored by dams has a temperature distinctly different from the rest of the river, and being stagnant, picks up unwanted things such as sand, besides encouraging algal bloom.
The water scarcity in India has led farmers to heavily depend on rainfall for cultivation. With 85% of the water being consumed by agriculture, we need better ways of managing this consumption. This management will not just require quick fix solutions but will also involve reflecting on the food consumption patterns of people. Rice based consumption has increased the usage of water for agriculture. So what are the various dimensions that we need to focus on to manage water effectively?
- Increasing the water retention capacity of soil
- Ways of replenishing ground water
- Moving to consumption of food that requires less water
- Better water storage and usage techniques
- Reducing the dependence on seasonal rain
- Enhancing the usage of indigenous crop varieties that require less water
The Indian agricultural ecosystem has given the opportunity for innovative water management practices by some simple and creative people. We are sharing some success stories here.
Hubli region in Karnataka is a very dry region and relies very much on rainfall. Borewells are a solution but almost 70% of the borewells had dried up in the area that received 997 cms of rainfall every year, water tables had sunk to 400 to 500 feet and farmers like Devendrappa were fast selling off their lands to repay their debts. Sankalpa Rural Development Society (SRDS) came up with an innovative way of doing direct borewell recharge at a fraction of the cost of digging one.
SRDS’ ingenious method uses a catchment pond that can store upto 3 lakh litres, to channel all the rain water, a 10X10X10 pit that acts as a primary filter around the borewell and tiny slits through the casing pipe to percolate water without loss.
The technique is very affordable: recharge requires an investment of around Rs.30,000-Rs.35,000 on an average while building a new borewell costs Rs.1,00,000- Rs.1,50,000. Four years and two good rain seasons later, as the SRDS method of recharge has slowly gained the trust of farmers and the results look impressive: 305 borewells recharged, 5,75,00,000 litres of water harvested and farms in 12 villages reaping good harvests.
Traditional Rain Water Harvesting
Parts of Rajasthan receive the lowest rainfall in the country. Large scale agriculture seems out of question in these areas. However, reviving traditional water harvesting practices has helped people in these areas immensely. Jethu Singh Bhati has been using these techniques and has been cultivating without irrigation.
Bhati has been extensively working on the paar system of rainwater harvesting. He took monetary help from the Centre for Science and Environment and purchased non-farming land from a panchayat on a five-year lease in 2003.
This traditional method of paar maximizes the catchment of water percolating into the sandy soil. The water flows from the agar (catchment area) and in that process percolates into the soil. To access the percolated water, 5 to 12 meter deep beris/ kuis (small wells) are dug in the catchment area using traditional masonry technology.
Around six to ten beris are constructed in an average paar.
He has also been using the irrigation free Khadin system of agriculture. According to Bhati, this system of agriculture has been in usage since 15th century.
A khadin, also called a dhora, is an ingenious construction designed to harvest surface runoff water for agriculture. Its main feature is a very long (100-300 m) earthen embankment built across the lower hill slopes lying below gravelly uplands. Sluices and spillways allow excess water to drain off. The khadin system is based on the principle of harvesting rainwater on farmland and subsequent use of this water-saturated land for crop production.
Millet based consumption
Indians in general consume more wheat and rice compared to other crops. In 2010, an urban Indian consumed 52 kg of wheat, almost twice the 27-kg annual consumption of the mid 1960s. As a result, since 1956, the area under millets has shrunk: 23%for pearl millet, 49% for finger millet, 64% for sorghum and
85% for small (or minor) millets.
Rice requires huge amount of water for cultivation and hence moving away from rice consumption gradually may help the water availability in the long run.
If we look at this graph, we see that cultivation of millets requires much less water than rice. Revival of millets can help in major way. Timbaktu Collective, an organization in Ananthapur District has helped local farmers transition from cash crops, especially groundnuts, to millets. Their interventions have given amazing results. The farmers who used to grow groundnut generally used to subsist on rice available from the PDS. After they started growing millets, they have included them in their day to day consumption. The chart below shows the yield of a farmer from 2011-2014.
- Barnyard millet has 531% the iron in wheat, 1,033% that in rice. Pearl millet has 314% the iron in wheat, 611% that in rice. Little millet has 265% the iron in wheat, 516% that in rice.
- Finger millet has 839% the calcium content of wheat and 3,440% that of rice. Pearl millet and wheat are comparable in calcium content, both of which have four times the calcium density of rice.
- Barnyard millet has 313% the mineral content of wheat, 783% that of rice; foxtail millet has 220% the mineral content of wheat, 550% that of rice.
- Proso, foxtail, pearl and barnyard millets compare with wheat in protein content. Sorghum and all millets are richer sources of protein than rice.
- Girls fed a diet composed of sorghum (60%) and rice (40%) recorded a high growth rate than those fed just rice, according to this 2015 study by the Indian Institute of Millets Research and the National Institute of Nutrition, Hyderabad.
There are many such success stories all over the country. What we need to do is to look at the situations locally, adopt and adapt these solutions.
One great way to increase the water retention capacity of soil is to using mulching techniques. Though plastic paper based mulching is common and has yielded good results, natural mulching through usage of coconut fibre is recommended. Mulching with coconut coir can retain water for a longer time and also reduce the evaporation of water.