|Indigenous technology knowledge for watershed management in upper north-west Himalayas of India (1998)|
|Chapter 2 - Soil and water management techniques|
In cold deserts of Himachal pradesh kuhls (water channels) are built along the hill gradient for maintaining proper gravity for irrigation (Fig. 2.2). Kuhls are commonly found in West Himalayas cold deserts. The technique for the preparation of kuhls for irrigation purposes seems to have originated since Babylonian times, it is still one of the commonest ways of bringing water to the crops. If the river has a steep gradient, water is diverted into a canal some distance upstream and led along a contour so that it can flow to fields by gravity.
In dry temperate zone, kuhls (wooden water channels) are generally made by making notches at the natural water sources and the water is diverted to the fields for irrigation to different terraces, using the natural gravitational flow of water (Fig. 2.3). Since the topography of the area consists of very high slopes and rocky terrain's, wooden water channels are used at many places as water passes from one place to another. The water channels are built and managed by the villagers with no government assistance. In the lower areas of H.P. bamboo pipes are commonly used as irrigation channels on depressions/small nala (Fig. 2.4).
In west Himalayan cold deserts for the optimum harnessing of water for irrigation, water channels are constructed along the natural gradients. The irrigation channels (kuhls) are diverted from river tributaries by making use of the natural gradients thus the level of water is higher than that of the cultivated fields.
In upper Kinnaur, the channels (kuhls) are simply dug in the ground to regulate the flow of water. However, where the digging of channels is difficult or the channel has to pass through a village path, underground channels covered with slates are constructed. However, in some parts the wooden channels are also used which are put like a bridge over the path. These channels are made by making a deep grove in the tree trunk or a thick branch.