The major rivers of Odisha and small water channels and streams are becoming dry very fast due to improper management of water systems of the State. The water sources generally originate from hills, hill-ranges and mountains.
Almost all the rivers, from small to big, which originate from the Eastern-Ghat region, used to be full of waters throughout the year although these rivers are not perennial like snow-fed rivers of the Himalayan range. But the same situation does not prevail now.
The river means an aquatic system, which is built by nature; where there are feeder channels, called tributaries, through which the main and the principal channel is fed by water. Other than the Himalayan rivers, all the rivers of India are rain-fed rivers. The rain-fed rivers are more subjected to pollutions and contaminations, including bank-erosions. The reason is that except rainy season, the streaming of water is not possible or it cannot happen due to non-supply of water from the sources. The source of water means, the whole amount or the volume of inflow of a river dependent on the extent of catchment areas of the principal stream of the river and catchment areas of several tributaries or the feeder streams of the principal river.
The catchment areas mean the areas from which water streams into the river-system and makes the river system alive for all practical purposes. The principal river or a tributary always starts or originates from a catchment area, which is known as rainfall-flow.
Other than the tributaries, a river system has branches and sub-branches and distributaries, which ultimately join the ocean; which is known as mouth of a river. The whole traversed land of a river is known from point of head of the river to mouth of the river.
In respect of branches, sub-branches and distributaries of a principal river, there is only one catchment area; although they have separate river mouths, individually or collectively. The sources of water of a principal river are from the principal catchment area and the catchment areas of tributaries. Other than the catchment areas, the hills also provide substantial quantity of water to the river for its sustainable existence.
If we take the cases of two major and important rivers of Odisha i.e. the Mahanadi and the Brahmani, we find that they are very badly polluted due to industrial developments and other human activities, which cause the dryness of the river. The total catchment area of the Mahanadi is 1,41,600 sq km out of which Odisha shares 40.3 per cent where as Chhatisgarh shares 52.9 per cent. Similarly the total length of the Mahanadi is 858 km. Whereas Chhatisgarh owns 286 km, Odisha owns 572 km. The annual flow of water of the Mahanadi is 59.16 billion cubic meter out of which 29.90 billion cubic meter is from the catchment areas of Odisha which amounts to 49 per cent of water available within the jurisdiction of Odisha. Odisha shares about 50 per cent of annual flow of the water. As the Mahanadi starts from the Amarakantaka plateau, which comes within the jurisdiction of Chhattisgarh, the State unreasonably claims 50 per cent of water for its uses which is quite unfair.
The major flood plain of the Mahanadi starts from Hirakud to Paradip. This requires proper management to sustain the water flow in the river. This also includes conservation of the riverine eco- system not only of the Mahanadi, but also of the 20 streams and sub – streams of the river. Similarly the river has 45 tributaries in Odisha. The tributaries like IB and Seonath come within the border line of these two States. Hence, there must be management plan and programme for sustainable use of the Mahanadi water.
Unfortunately Odisha’s programmes at sustainable management of the river are far from being satisfactory. The regular tree felling and de-vegetation of the command areas of water resources leads to drying of the river. Unless the natural forests are conserved, nothing on earth can save the river. So, the administration should carefully look into the matter.
If we analyse the case of Brahmani river system which is the second major river of the state, it has two major tributaries like Sankha and Koel, and has eight branch streams other than the main stream. The total length of the river is 701 km, out of which 149 km is within the State of Odisha and the rest 552 km comes within the State of Bihar.
It originates from the Chhotnagpur plateau of Bihar, and enters into the State of Odisha from Sundargarh district. It is an absolutely hill stream; which passes through revenue districts of Sundargarh, Deograh, Angul, Dhenkanal, Jajpur and Bhadrak and joins the Bay of Bengal being associated with the river Baitarani of Keonjhar – Banai plateau. The eco-systems of the two rivers are very rich. The Brahmani and Baitarini are perennial to semi-perennial throughout the year since the eco-systems of the rivers are rich. However, due to rampant felling of green belts along the sides of the rivers, the situation has changed for the worse. The perpetual soil erosion, the deterioration of soil value and non formation of new soil profile have deteriorated the moisture conservation and sub-soil water management of the nature.
The burning example is Mandar Ghat of Kamakhyanagar sub-division of Dhenkanal district and Mandapal-Ghat of Talcher sub-division of Angul district. The river systems of Brahmani and Baitarani including Mahanadi once were used for rafting and floating of timbers and bamboos to different parts of the State. Such navigation of goods and forest products now is not possible due to dryness of stream flow.
(The writer is a former senior forest officer and an environmentalist. Tel no 9937460649)
