Future of farming depends on saving every drop

Surinder S Kukal

THE utilisable water available in Punjab is 56 billion cubic metres (BCM) against the demand of 66 BCM. The deficit of 10 BCM is met through overextraction of groundwater. The average annual rainfall in the state has decreased from 490 mm (1970-2020) to 444 mm (1998-2020); prolonged dry spells and skewed distribution of rain are among the other key factors.

INFOCUS: Agriculture — Water conservation

Most of the annual rain occurs from June to September. Also, the average annual rainfall in the catchment area of the Bhakra Dam has decreased from 1,124 mm (1983-2018) to 1,056 mm (2014-2018). Increasing urbanisation (from 217 cities/towns in 2011 to 237 in 2021) has led to decreased groundwater recharge and higher runoff. Consequently, the water table in the state is falling at an average annual rate of 65-70 cm. Currently, out of 150 blocks in the state, 117 are overexploited.

Water metering and rationing are a must to encourage judicious use of this natural resource. The supply of groundwater or surface water should be rationed as per good irrigation practices recommended by the state agricultural university. The quantum of water for irrigation as per good practices should be provided free of cost, but the water consumed over and above the recommended norm should be charged at high rates. Farmers who save groundwater through innovative techniques should be rewarded in cash or kind.

The state has 57 blocks with groundwater extraction of more than 200%, out of which 12 have groundwater extraction of even higher than 300%. Also, there is a huge gap in the generation, treatment and use of wastewater. The sewage water treatment capacity is 1,827 million litres per day (MLD) against 2,500 MLD of the total generated, of which 1,355 MLD is actually treated and only 280 MLD is being used.

The groundwater in 8% of the area, covering 10 blocks in Barnala, Moga, Patiala and Sangrur districts, is expected to deplete beyond the 50-metre depth by 2030, and 19% by 2040. Even without any change in the quantum of rainfall, the actual evapo-transpiration is expected to increase by 5% by 2030, 6% by 2040 and 8% by 2050. The water demand in the state is thus expected to increase from the present 66 BCM to 70 BCM in 2030 and 72 BCM by 2050. The treated water potential for reuse is expected to increase from 0.8 BCM in 2020 to 1.1 BCM in 2030 to 1.8 BCM in 2050. A higher number of extreme wet years along with dry years are expected to be witnessed in the future, leading to a higher magnitude of floods and droughts. The average temperatures are projected to increase by 0.5-2°C in different regions of the state by 2050. The total runoff is expected to increase by 5% and 7% by 2040 and 2050, respectively. The surface waters are expected to decrease from 14.8 BCM in 2021 to 14.6 BCM by 2030 and 14 BCM by 2050.

The challenges

Increase in dry spells: The occurrence of dry spells has been increasing in the region. Data shows that despite otherwise normal or higher rainfall years, the increased frequency and duration of dry spells is leading to higher extraction of groundwater.

Inadequate utilisation of rainwater: Punjab, on an average, receives about 550 mm of rain annually. The northern part receives about 900 mm, the central area about 650 mm and the southern part 300 mm. About 75-80% of the annual rain is received in a span of two-and-a-half months (July-September). Based on a runoff co-efficient of 90% in urban areas and 15% in rural ones, around 5.3 BCM of rainwater goes as runoff into streams and rivers.

Mono-cropping system: Rice-wheat is the major cropping system in the state, with rice occupying more than 30 lakh hectares. It requires extraction of 2,400 litres of water to produce 1 kg of rice as per recommended practices of irrigation, whereas based on commonly prevailing farmers’ practice of irrigation, this figure touches 3,400 litres. The methane emissions from rice fields add to the greenhouse gas emissions that are responsible for increased temperatures. Rice replacing some of the area under cotton in south-west Punjab has resulted in a higher incidence of whitefly and pink bollworm attacks due to higher relative humidity.

Non-judicious and inefficient use of water: Every sector (agriculture, industry, domestic) is using water non-judiciously. Some farmers not only tend to continuously flood the fields but keep their tubewells running even if it is raining.

Provision of free electricity: Punjab’s farmers get highly subsidised electricity to run their tubewells. This has put a huge burden on the exchequer, as indicated by the subsidy bill of Rs 7,180 crore for 2020-21, apart from overexploitation of groundwater.

Quality issues: The quality of groundwater deteriorates as the water table goes down. The area with unfit water has increased from 11% to 29% in seven years.

The way forward

Crop diversification: A three-pronged strategy should be followed, based on water budgeting of blocks/clusters, niche crops’ (other than paddy) value addition, and improvements in market infrastructure.

Water metering: Water metering and rationing are a must to encourage judicious use of this natural resource. The supply of groundwater or surface water should be rationed as per good irrigation practices recommended by the state agricultural university. The quantum of water for irrigation as per good practices should be provided free of cost, but the water consumed over and above the recommended one should be charged at high rates.

Water credits: All farmers who save groundwater through innovative techniques like micro-irrigation, crop diversification or preferred use of canal water should be rewarded in cash or kind.

Revival of drains: The drains, most of which are presently defunct, need to be desilted and provided with gabion-type structures at fixed intervals to ensure natural recharge of excess runoff water. These drains could also be linked to rejuvenated village ponds, wherever possible.

Canal water recharge: Canal water that remains unutilised due to lower demand during monsoon must be used for groundwater recharge. A committee of experts should redesign canals to ensure their ruggedness and low maintenance.

The author is a member of the Punjab Water Regulation & Development Authority

Send your feedback to letters@tribunemail.com