Watermill 

Zahra AL-Abri

UNESCO's Chair on Aflaj Studies-Archaeohydrology

A watermill is an ancient, traditional tool used to grind the grain by the hydraulic power of stream water like falajs.

Its history dates back to the first century BC, at the time of the Greeks and Romans. As for Oman,surveys conducted by Harvard University indicate its presence since the early Islamic eras, approximately around the eighth century until the tenth in the Wadi Al-Jazi region in willayat Sohar.

The millstone consists of two pieces of flint or basalt stone on top of each other, and there is a hole in the upper stone to put grain, while the lower stone is connected to a piece of metal from which wooden fans extend to rotate the axis of the mill. 

The working principle of the water mill is based on directing a water force using the Falaj channels and then descending vertically towards the basement or the mud mill room, where the hydraulic forces of the water move the mill wheel or its fans, which is what is known locally as ” alwarqah” or the paper. By moving the axis the mill rotates and the grains are grinded between the two pieces of stones.

The produced flour from the milling process is collected in a channel made of clay, plaster or sarooj (local cement). In some mills, a piece of fabric or leather is placed around the mill.

Water mills are located in a number of willayas, including Sohar(Falaj Al-Mutarid), Al-Hamra (Falaj Al-Hamra), Nizwa (Falaj Al-Khatmeen), Qurayyat (Siaa), Nakhl (Falaj Al-Gharid), Bahla (Falaj AL Maiytha),AR Rustaq (Falaj Al-Mayassar), Al-Awabi and Al-Seeb.

The water mill in the Wilayat of Al-Hamra, - which was built on the stream of Falaj Al-Hamra-, was a public endowment for all people, with their agreement, and the majority of its users live near it. It is supervised by a woman by virtue of its being located within the precincts of her house, and her rent is either a part of the flour or a few baisas (Omani coins), and some of the palm trees surrounding the house are still belonging to the endowment, but the water mills have no ruins at the moment.

As for Falaj Al-Mutarid at the archaeological site of Arja in Wadi Al-Jazi in Sohar, archaeological surveys indicate the presence of traces of four water mills, which is the first willayah believed to have introduced the water mill system due to its urban expansion in the early Islamic eras and the expansion of its agricultural area. It was also at the top of its economic activity, especially mining copper. Where the height of the downstream of the water in one of them is about 8.5 meters, while the size of ​​the room or the vault of the mill is about 24 square meters. Wadi stones, seashells, sandstone, blue and grey coloured volcanic rocks, in addition to gravels mixed with sarooj, were used in their manufacture.

In the village of Tawi Al-Seih in  Wilayat of Al-Awabi, and according to what was mentioned in the Omani Encyclopedia, there are water mills with an area of ​​13.5 square meters and the height of the downstream of the water is 1.5 meters.

Also, traces of six water mills were found in the Wilayat of Al-Seeb along the Gili Falaj. The source of its water is Wadi Al-Khoud, some of them goes back to the Abbasid era and some to the Sassanid era, according to archaeological surveys.

The types of water mills differ according to the waterfall, as well as the position of the mill wheel. In Oman, the Greek mills or mills with a vertical drop and a horizontal wheel were famous, and they depend on the height of the waterfall, which is usually 4-8 meters high. This type of mills is suitable for areas with hilly and mountainous terrain, where the flow of water is in sloping streams, which provides the hydraulic pumping necessary to operate the mills.

The Islamic Republic of Iran is still using water mills powered by the Aflaj water forces, specifically in the province of Yazd. Moreover, in the Kingdom of Morocco, there is a complete model of the water mill similar to the Omani model in the Museum of Water Civilization in Marrakesh.