Home UpIrrigation 1: Ancient Methods
Heat and Dust isn't a bad image for most of peninsular India most of the year, but farmers have found many ways to supplement the sparse rains. Here are some examples, shown as they were between 1981 and the early 1990s.
Wells in India are often massive excavations. In 1950, India had about 3.5 million such "dug wells" more or less like this one and about 6,000 narrow "tube wells." The ratio has changed greatly since then, with the explosive rise of tube wells and the passing into picturesque obsolescence of the dug. Still, dug wells remain in use particularly in hard-rock areas where yield depends on tapping a great many rock fractures. This example lay within the command area of the Tungabhadra Project high-level canal, between Hyderabad and Bangalore.
The cheap alternative: unlined but functional so long as the rock walls are hard enough.
Excavation of these wells is strictly manual, with rubble hoisted by hand.
Lifting the water: a swing basket—a simple but very energetic method.
Upgrade One: the humble picottah,, identical to the Egyptian shaduf. A bucket drops down to the water in the well. Raising it is made easier by the counterweight at the end of the balance beam. Only a few feet of lift are possible, though in Egypt these devices used to be arranged in series.
Upgrade Two: the kabalai. Once the bucket is raised, a tug on a thinner rope drops the tube or trunk, draining the bucket into an irrigation ditch. A related device called a mhot takes two men to operate, one emptying the bucket.
Upgrade Three: the Persian wheel, here on a chilly morning on the Ganges Plain. A bullock goes around in circles, turning a shaft connected through a spur gear to another shaft controlling the bucket line in the background. The buckets descend to water in a dug well. They spill into the ditch in the upper left.
The buckets don't have to be fancy.
Here's a way to skip the well altogether: a crude dam blocks a river to divert its flow into a ditch. This is the headwork of one of the Vijayanagar channels off the Tungabhadra River.
The irrigation channel is "open-mouthed," reaching into the river then narrowing as it begins to leave the river's course. This channel is ancient, though the weir has been repeatedly rehabilitated.
A grander version of the same kind of irrigation system: this is the Asif Nahar, a 60-mile-long canal that diverts water from the Musi River ("the river of Moses"), downstream from Hyderabad. It was built in the 18th century and has the ingenious variation of feeding small reservoirs along the line of the canal, so that water will be available when levels in the Musi decline and the canal runs dry. (A similar design in China is vividly named "melons on a vine.") Recent upstream reservoirs have kept the Musi so low that the Asif Nahar is not very useful anymore. Here it's choked with vegetation. The banks are lined with humble but tough Prosopis juliflora, or mesquite. Watch those thorns! They'll cause the devil of an infection.
Canal cleaning under way on the Asif Nahar. Actually, the villagers are fishing, following a brief spate in the channel. In the process and at the instigation of an irrigation officer, they pull up some of the weeds. The stone-slab fencing is common in this granite-rich part of India.
And yet another approach: for thousands of years reservoirs called "tanks" have been built in South India: indeed, the word tank is indigenous and refers to such small lakes. In this case, the lake isn't so small: it's the Ramappa Tank, built by the same Kakatiya kings who built the nearby Ramappa Temples (See South India: Ramappa.) The facing on the dam was added by a British engineer named Roscoe Allen, who about 1900 went around the Nizam's Dominions fixing up a small fraction of its 18,000 tanks.
A view of the tank from the resthouse at the south end of the dam.
At the toe of the dam, an outlet tunnel releases water into a canal: this is paddy country, at least when the reservoir levels permit its cultivation. Sometimes they don't.
Looking downstream.
Another example of Roscoe Allen's tank-repair work: the spillway of the Bhongir Tank, northeast of Hyderabad.
And yet another: Pakhale. Like Ramappa, this is a 13th-century undertaking rebuilt by Roscoe Allen. It's big enough to support not only a monsoon crop of paddy but a dry-season crop one year in three. Lord Curzon bagged a tiger in the surrounding teak forest.