R P KAPUR: Build canals, not dams

Even after submerging lakhs of acres of fertile land and uprooting thousands of farmers and their families in constructing big dams, a very large quantity of valuable water flows down to the sea. High-altitude canals are a better way to preserve water that flows across the country almost throughout the year, either through the monsoon or through melting of snow.

So what's a high-altitude canal and how can it be constructed? At the junction where fast flowing water is available, a small dam (about 20 metres high) can be build. Next to it, a well "" about 100 feet deep and having a 100-metre diameter "" can be constructed. The walls of this well should be 10 metres above the ground, and with an inflowing gap of 6 by 6 metres opening on the dam side. At a height of around 8 metres, concrete canals (about 20 metres wide and 10 metres high) should be constructed and connected to the well. The canal should be 5 km long.

After filling the well, the dam water will automatically flow into the constructed canal. At the end of the canal, on the right side, a second well with a 100-metre diameter and a depth of 11 feet should be dug "" the well should be constructed in such a manner that water flows into the wall (which has a gap of 6 by 6 metres) of the well from the existing canal side. When this well is filled to the brim, its water will flow into the second canal. The walls on second well should be higher than those of the first canal by 10 metres. A second canal, five kilometres long and 20 metres wide and 10 metres deep, is then to be constructed adjoining the first canal. It is in this canal that overflowing water from well no. 2 is to flow through a gate made in the wall of the well at a level that water goes out with full speed from the well into the second canal.

About 100 metres before the end of the first canal, an adjustable flood gate should be constructed. Similar floodgates should be constructed after 100 metres of the beginning of the second canal. In this fashion, a third, fourth, fifth and sixth canal should be constructed along with the wells and flood gates. The height of the sixth canal should be 18 metres.

Once the water from the dam start flowing through the wells, we will see that the gushing waters will not only fill the wells to the brim but will carry the water to the end of the sixth canal. At the end of the sixth canal, another (seventh) well should be constructed. In this way, we will have 30 kilometres of canals full of fresh water. We can extend the length of this canal further by another 30 kilometres by constructing another six wells and canals, in a declining manner. For taking out water from wells, water pumping sets, operable both by electricity and diesel need to be installed.

In October, operate well no. 7 and the water coming out can be poured into canal no. 6. Simultaneously, open the gate of canal no. 6 and connect it to well no. 6. When about 25 per cent of the water of canal no. 6 flows into the well no. 6 and it stands rejuvenated, the pumping station of well no. 6 should be stopped and the entry gate to this well closed. Now, the pumping set of well no. 6 should be operated and the water coming out should be added into canal no. 5. Simultaneously, the overflowing water of canal no. 5 will flow into well no. 5. When 25 per cent of the water of this canal gets into next well, the level of water in well increases and the canal water gets freshened. This procedure should be continued till well no. 6.

In November, operate the pumping set of well no. 7 and the water coming out should be poured into canal no. 7, constructed on the declining side. This process of pumping out water into the declining canals and then into wells should continue till the 12th canal.

This process of changing water should be done every alternate month so that fishes get fresh water after every two months. The flood gates are to be used for filling the canals, controlling its waters so that they don't flow down and also to facilitate running of boats, and so on.