Traditional watermills: dying wisdom

Traditional watermills have been in use in the Indian mountain region since time immemorial. This eco-friendly device that harnesses waterpower for local production is a symbol of local technical excellence and the traditional wisdom of the people inhabiting the mountain region. In India, experts estimate that the water-mill originated somewhere in the northeastern region around the 7th century AD. The system worked harmoniously with nature for over 2700 years and is abundantly scattered across the Himalayas (Figure 1). The widespread use of watermills and their popularity owed much to their simple and cost-effective mechanism.

According to one estimate, there are nearly 200,000 watermills in the Himalayas from Uttaranchal, Himachal Pradesh, Jammu and Kashmir to the northeastern states of the country. In Uttaranchal alone there are about 70,000 watermills. As mentioned above the design of traditional watermills is centuries old. Their low output (5–10 kg of flour per hour) does not provide enough profit to the owners today.

In recent years, watermills have thus started to fall into disuse. This is probably also because they were serving only the remote rural communities of the Himalayan region and their potential remained hidden or was neglected. In the absence of appropriate technology, water-mills were not used for any purpose other than grinding wheat, maize, and rice. The importance of watermills was further overshadowed by the introduction of diesel and electricity powered mills, and the inclination of the people towards high-speed grinding machines. Moreover, owners of traditional watermills were often forced to descend to the plains to seek more lucrative employment. They were unable to do anything to save their watermills.

The present article discusses the technology model developed and being replicated in Garhwal Himalaya, which has shown potential for improving the efficiency of traditional watermills, not only for flour grinding, but also to produce electricity to meet local energy requirements and promote multipurpose use of decentralized power and enhance local income.

Upgraded watermills: inducing economic potential

A watermill is a traditional device run on the principle of using the kinetic power of a water stream running on a gradient. Traditionally, the mill functioned in a single mode to grind flour. Watermills in the present discussion are upgraded as follows:

Models using such modern technology have been developed by the Himalayan Environmental Studies and Conservation Organization (HESCO) in Dehradun, a science- and technology-based NGO. These models have won community approval and are widely accepted, as shown in the case study presented below. Their technology in terms of water use and management (upgraded watermills, agro-processing and electrification, nursery management, beekeeping, etc) has been standardized for hilly conditions.

The turbine is simply an upgraded local design. The new system replaced the wooden water wheel with a cast steel runner mounted on a steel shaft. The flat wooden fins of the water wheel have been curved to harness maximum energy (Figure 2). To allow free rotation of the wheel, a single steel ball bearing is used at the bottom of the water wheel, increasing efficiency to a significant degree. The other parts of the water-mill—such as flumes that bring water from channel to turbine; wheels attached to the turbine to obtain the appropriate number of revolutions per minute for electricity generation; and other agro-processing applications such as dehusking and flour grinding—were upgraded depending upon the quantity of water and head availability.

A ball bearing instead of an axle increased efficiency by 70%, while innovations in the blades brought an increase of 120%. Altogether, these measures have increased the power and efficiency of the traditional single mode system to a significant degree, by 80–90%. Such changes have inspired improvements in numerous watermills across the Indian mountain region to generate power commercially and put it into grids (Figure 3).

Integrated technology model for multipurpose use

Given the abundant availability of land and water in the vicinity of improved watermills, water-millers have been encouraged to initiate floriculture-related activities linked to beekeeping for income generation. Low-cost bee boxes (which make use of the stems of the locally available invasive weed lantana) have been developed and introduced. It was found that 2–10 bee boxes can be maintained easily at one watermill site, which gives a return of about Rs 26,000 (US$580) per annum to the water-miller or local villagers who market honey.

Since water is an essential component for mills as well as for fisheries, a composite fish culture was made part of this integrated model to get the maximum advantage from available water. A tank of 1000 square feet (∼93 m²) was constructed, and after appropriate treatment, different types of carp were introduced. The advantage of carp is that they are in demand, accepted by local people, and fetch a good income for pond owners and mill owners. This is not the first time they have been introduced and cultured in the region. In addition, integration of vegetable and ornamental plants in areas measuring ∼90 m², with assured irrigation from the water channel of a watermill, provides further returns to water-millers and the local community. These activities are seasonal and can be integrated and managed locally.

The whole technology package of water management has focused on the watermills, which are abundant and scattered throughout the Himalayas. Technological upgrades with small and affordable changes have improved the functional efficiency of the watermill in a user-friendly way to generate power. Besides providing shaft power, watermills can now be converted into electrical generating systems that can be used by villagers for lighting at night and operating small-scale industry in the daytime. The entire scheme of integrated use of water shows how a water stream can be useful to the local community through various applications. Specifications for an integrated watermill package, including adoption factors, technology flow, and development indicators, are given in Table 1 and Box 1.

Community empowerment: adopting technology to improve livelihoods

Considering the economic incentives for households and communities as a whole, the adoption of this multipurpose model has had an important impact on socioeconomic conditions. Successful adoption of this model using modern technology has been reported from about 100 locations in Western Himalaya alone, while development agencies in other mountain regions are adopting it in remote villages with the support of extension agencies and the army. Enterprising millers who had set up diesel and electric mills are now switching over to the improved watermill model because of cost-effectiveness, multipurpose benefits, and the environmentally friendly way this system functions. Technology flows from village to village and other Himalayan regions were found to be very effective and efficient, but it was noted that this requires initial stimulus and continuous encouragement from local NGOs and development groups to empower communities with a complete technology package in partnership mode, ensuring forward and backward linkages.

Replicability and outlook

This evidence suggests that if improved watermills could be directly used to generate power across the Himalayas, local power needs could be sufficiently met while surplus power could be transmitted to far-flung and remote mountain areas through small hydropower grids. Indeed, upgrading of existing watermills in the Indian mountain region would lead to considerable power generation, considering that each watermill has the capacity to generate 5 kW of power. It is estimated that 2 million people—or nearly 500,000 families with 4 members each—could directly benefit from technological upgrading of watermills and related activities.

The multipurpose use of this field-tested technology model, with careful approaches to innovation and transfer, can play an important role in the overall development of local areas in terms of commercial activities. For traditional activities in the mountains, there is a need to strengthen the knowledge, skills, and infrastructure already available and scale them up in a business model, in order to bring significant impacts in terms of better output and efficiency. A range of skilled and unskilled employment opportunities for pre- and post-installation services related to electricity supply and mechanical and civil work can be generated. If properly pursued, this opportunity would provide immense employment opportunities to local young people in mountain regions, who are currently migrating to bigger cities or industrial areas in search of jobs.