Ahar pynes: Traditional flood harvesting systems of South Bihar

Ahar pynes, the ingenious community managed irrigation systems of South Bihar

Ahars and Pynes, the traditional irrigation systems of South Bihar were first developed during the times of the  Magadh dynasty nearly 5000 years ago and continue to be particularly popular in Gaya district of South Bihar. The system is highly sophisticated and well managed and is considered to be one of the most reliable sources of irrigation by cultivators in Bihar.

The Ahar pyne system, with the help of its network, not only helps in transferring river water to nearby agricultural fields to irrigate kharif (mostly paddy), rabi (wheat or gram) in winter season when water is available, but also sustains the water table in the area.

Simply put,  it is a diversion-cum-storage system wherein Ahars include  man made earthen storage structures that have small embankments on three sides and store harvested river water while Pynes are diversion channels or carriers of the harvested water that is drawn from the river from a temporary head to be stored into the Ahars. In a suitable terrain, the main Pyne often branches into  into interrelated Pynes and Ahars to form a network of channels drawing and storing river water.

The system is mostly used for paddy cultivation in Bihar where rainfall is scanty, farm lands are sloping and undulating and the soil is clayey or sandy with little water retention capacity. The system has attained its highest level of development and social acceptance amongst cultivators in Gaya district.

Ahar pynes also play an important role in recharging groundwater. For example, The Ahar, known as Surajkund, in Nalanda district, has five wells to recharge the groundwater. Ahars also have waste-weir to discharge excess water, which finds further use in the form of a new Pyne. The excess water, if necessary can be released in a small stream as well.

Ahar Pynes are now in a state of neglect

Ahar and Pyne system suffered serious neglect in the British era with very little efforts being made to maintain and repair them and the introduction of modern irrigation systems further enhanced their neglect. The use of ground water through wells and tube-wells added fuel to the fire, impacted the ground water table and largely diverted the attention of the people and government from these traditional irrigation systems and this resulted in a complete collapse of this valuable community managed system.

Recently, the importance of these traditional irrigation systems for Bihar is being realised and the Bihar government is making concerted efforts to revive and restore the Ahar pynes. It is thus necessary to understand the concept behind Ahar pynes  and study the hydrology of this ancient system in its totality. Proper understanding can greatly help to build a bridge between the program managers of the governmental system and the community to undertake Ahar pyne restoration, rejuvenation and help in equitable management of water resources.

What needs to be done

The restoration and rejuvenation efforts for Ahars and Pynes should primarily address the following concerns:

• Develop a proper understanding of the natural conditions and physical configurations of the land of south Bihar, the rain fall patterns (quantity and characteristics) and the river system (Basically flow pattern and silt deposition over the supply season) of the area. These natural factors decided the technical design of the ancient system and assured cultivation and ground water sustainability for non-monsoon flows in the river system, and need further exploration.
• Development of community controlled equitable arrangement for distribution of available water after renovation. The desired user friendly mechanism has to be conceived within the framework and provisions of the Panchayat system.
• Non-monsoon flow is decreasing in practically every river. South Bihar is no exception. Rivers in this region are also under stress. The winter crop needs optimum water and hence, those who are dealing with the rejuvenation effort of the ancient system, will have to ensure optimum flow in the donor river. This is necessary for sustainability of the benefits.
• The ancient system was developed on rivers of south Bihar. The rivers of south Bihar are directly or indirectly tributaries of the Ganga. The river bed of Ganga is rising due to siltation. This siltation, in turn, is raising the height of river beds of tributaries and introducing changes in the landscape. This has modified/changed the relationship between the land and the rivers in the region. This needs to be understood for technically sound restoration efforts.

These concerns are real. It is therefore urgently necessary to undertake a detailed study of the Ahar pyne network, identify problems  and come up  with solutions by involving the community in the effort. For example, a simple GPS status app, downloaded from play store of a mobile can facilitate the stake holders to broadly determine altitude, longitude and latitude of the hot spots indicating disturbances in the slope of the land that could affect the Ahar pyne functioning.

Proper understanding of hydrology and natural parameters will also enable and build bridges between the program managers of the government departments and local communities to undertake Ahar pyne restoration, rejuvenation and water management.

The federation of Ahar pyne management committees could be conceived and put in place to deal with all the issues. With the support of the federation of Ahar pyne management committees, livelihood opportunities for the local communities can also be explored and put in place.

In this context, there is an urgent need to develop a sustainable and nature friendly model of Ahar and Pyne restoration and rejuvenation along with establishing democratic community based system (Federation) to equitably distribute available water of the system and deal other concerns.

It is important to undertake studies for better understanding of the hydrology of the Ahar and Pyne system and for suggesting the technically sound approach and putting in place the socially acceptable model for community participation/ownership.

This could be done by appointing an expert committee, under the chairmanship of a renowned Ahar and Pyne system expert, who will submit a report/guideline, so that a technically sound strategy and operational guidelines could be framed and the Ahar and Pyne restoration large-scale campaign can be launched in the state.  

K G. Vyas is a geologist and a well-known writer on environmental issues. He has served as a consultant for the Rajiv Gandhi Drinking Water Mission in Madhya Pradesh.