Karez system is one of the foolproof and systematic water supply systems adopted by our earlier rulers in and around Bidar city. This system is known for its uniqueness in design and concept. The Muslim kings of Bidar, apparently under the expert guidance of Persian engineers, have laid out subterranean canals passing through the heart of Bidar city.

The one which still exists at the village of Alliyabad near Bidar is largely carved out from the existing natural rifts. In fact, it is a magnificent piece of water management engineering taken up by the Muslim rulers of Bidar during their times to ensure clean water for drinking and irrigation.

This natural cave tunnel is 25 feet wide and many stories are doing the rounds as to why the rulers of that period felt the need to widen existing natural rifts in the form of such huge tunnels. According to Prof B R Konda, the rulers came up with such concepts to ensure clean water to their subjects as there was neither electricity nor pump sets they could bank on.

Hence, under the guidance of Persian experts, they carved out large caves from the existing natural rifts from where water in the form of streams was coming out and followed the path of the stream till the next source of water (like open wells), he added.

Meanwhile, they even constructed manholes 90-120 feet apart on the top of the rift to ensure natural air and light. Even to this day, 21 such manholes can be seen on the tunnel which ends at a large open well in the agricultural fields of Naubad village, treading the path of over 2 ½ km.

And there are some technical aspects to go along with. When the existing tunnel is on the sub-terrain, the rain water which collects on a higher terrain percolates below the ground, under 60 to 70 feet, and the water thus percolated takes the shape of streams while it comes out of the cave, which is then used for the purpose of drinking and irrigation. The other end of the terrain was connected to open wells, thus ensuring a continuous supply of water in the summer too.

One such marvellous piece of water management existed in the heart of Bidar, where one of the subterranean canals known as Jamuna Moori, headed from Fateh-Darwaza to the parallel moats of the main fort area. It has a historic presence on the archeological maps of the district. And, the manholes of this canal were seen till recently but, with the passage of time, they have all gone underground.

Very little can be done to trace the canal in the heart of the city, what with the amount of excavation undertaken at the cost of development. However, the one at Alliyabad is in dire need of conservation. The authorities concerned should take immediate steps to promote the place and the canal as an interesting tourist spot so that people can learn about the ways and means adopted by our rulers in the past for water management.