The gharat is a horizontal-wheel water mill, driven by a stream through a wooden chute on to angled paddles, turning a millstone directly with no gearing. It grinds slowly and it grinds cool.
They were built along the hill streams of the Kandi belt and through the Shivalik valleys, and were owned by families or by villages, taking a share of the grain as payment.
The design is very old and it is the same throughout the Himalaya from Kashmir to Nepal. It costs almost nothing to build and nothing at all to run.
Electric mills and falling stream flows ended most of them. A few survive in Himachal and a small number on the Punjab side, mostly derelict.
Flour from a gharat is preferred by people who have eaten it, because the stone turns slowly and does not heat the grain. That is a testable claim and it has not been tested.
The whole machine has one moving assembly and no bearing that cannot be cut from wood, which is why a village could build one and keep it running without buying anything.
The water right was the valuable part. A gharat depended on a share of a stream at a particular point, and those shares were held, inherited and argued over in exactly the way land was.
Electric chakkis replaced them from the 1960s. A few still run in the Himachal foothills and almost none work in Punjab now.