Devise plan to save crops from a watery grave

Surinder S Kukal

MONSOON fury ravaged Himachal Pradesh in July and August this year. Punjab and Haryana suffered, too, as the huge runoff water from the catchment areas located in the hill state, coupled with water released from the reservoirs into the rivers, led to the inundation of vast tracts of agricultural land. Many crops, including water-guzzling paddy, got damaged on lakhs of acres in Punjab and Haryana. It is feared that paddy yield in these states may decline by around 30 per cent. The situation could not be handled by the two states due to certain challenges.

More than 75 per cent of the annual rainfall in the region occurs during a period of two-and-a-half months. The three-day spell of rainfall (about 300 mm) in July accounted for more than half of the average annual rainfall in Punjab and Haryana. The excess rainfall (436 per cent of the long-term average) during July in Himachal Pradesh led to a huge runoff from the Himalayan state into the rivers of Sutlej, Beas, Ghaggar and Yamuna, causing numerous breaches and flooding of agricultural fields.

Degraded catchments

The major reservoirs in the region have their catchment areas in the Himalayan states of Himachal and Uttarakhand. These catchment areas have been denuded of their natural vegetation by large-scale, unplanned deforestation over the past couple of decades. This has led to huge siltation of the reservoirs. For example, the sediments entering the Gobind Sagar lake from a catchment area of 36,000 square km in the Himalayas have reduced its water storage capacity from 9.27 billion cubic metres (BCM) to 7.14 BCM. Also, the heavy runoff and unabated soil erosion in the catchment areas trigger floods in the plains of Punjab and Haryana. Due to anthropogenic activities in the hill states, the floods in the plains threaten agricultural productivity of the food bowl of the country.

So-called development activities, such as the construction of roads, bridges, tunnels, etc. in the catchment areas without proper planning and execution, have rendered the landscape unstable. Unregulated inhabitation in the catchment areas has aggravated the situation by blocking the natural path of running water and concentrating its flow velocity. The concentrated flow damages structures such as roads, buildings and embankments of rivers and streams, leading to damage to crops in Punjab and Haryana.

Managing floods

The natural landscapes in hills and plains, which have been altered over time, need to be restored. The provision of systematic waterways in recently degraded landscapes and their isolation from any type of man-made obstruction needs to be ensured. The basic principle of reducing runoff and sediment load from the catchment areas should be adhered to through a dedicated afforestation programme.

In the plains, too, the embankments of rivers and streams need to be strengthened, besides curbing stream-bank erosion. The floodplains of the rivers and streams must be restored by removing structures or habitations. The excess water in rivers should be diverted for irrigation purposes through the existing canal system or an alternative carrying system. This becomes more important during situations like the one witnessed recently — there was abundant floodwater in some blocks of Punjab, whereas farmers in other blocks had to irrigate their fields through groundwater extraction. Let this disaster be turned into an opportunity for groundwater conservation.

Desiltation of water bodies

The reservoirs of various dams in the region need to be desilted periodically to ensure a minimum of 50 per cent of dead storage available for water, apart from live storage. Similarly, the rivers and streams in the plains must be cleared of deposited sand (or silt near the barrages) through scientific mining to sustain their carrying capacity. The village ponds, which get runoff water from the whole village/catchment areas, also need to be desilted periodically with the twin objectives of groundwater recharge and water use for animals and other purposes.

Rainwater management

Rainwater in the hills or plains needs to be managed in such a way that the runoff accounts for not more than 25 per cent in the hill states and 10 per cent in the plains. Unfortunately, during the monsoon season, more than 70 per cent of the rainwater in hill states goes as runoff water into rivers and streams and, ultimately, oceans. This water must be conserved in the hills as well as the plains. Most of the catchment areas of hydroelectric reservoirs are in Himachal and Uttarakhand, while rivers and streams carrying runoff water flow into the plains via these reservoirs. Thus, there is an urgent need to tackle the rain runoff issue on a regional basis rather than by individual states; any activity in a hill state may have consequences for the plains. In this direction, a Regional Water Commission for the states concerned should be established, aided by a regional group of land and water experts. The commission, on the advice of the expert group, should draft state-specific water and flood management plans on short-, medium- and long-term bases. These plans should be executed effectively by the states. Such a collaborative approach is a must to minimise flood-induced damage to agriculture and also to utilise the rain/runoff water to recharge groundwater.

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