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There is absolutely no doubt that flood is a natural phenomenon but its impact is much affected by human intervention.

In Baitarani river context some of the major causes can be summarized as follows.

1. The drainage pattern of Baitarani river basin (central plateau) is dendritic type and flash flood is a natural character of such type of drainage pattern. Again since the upper catchment of Baitarani is full of hillocks and occurrence of a large number of drainage lines allow the run off generating over there to gush into the main river with greater force in very short span of time.The lower part of Baitarani is a part of greater Mahanadi &Brahmani delta, which hasn’t very less no of drainages.
2. Baitarani is a highly meandering river. In meandering channels the flow is highly turbulents and forms eddy currents which very often leads to sudden overflow of the embactments causing inundation of surrounding areas.
3. Due to heavy mining activites and practices of shifting cultivation in the upper catchment a large quantity of sediments are added to the river during monsoon seasons. This lowers the carrying capacity of the river and thus even a medium size rainfall can cause high flood in Baitarani.
4. The shallow aquifer conditions, water table nearer to the ground level, spread of water logging areas, swamps, and esturines etc. do not allow precipitation & thus compound the impact of flood.
5. There is no major diversion channel to control flood in Baitarani river Basin
6. The upper catchment i.e the central plateau comprises of metasediment & controlled by severe fault & shear zones which contributes more sediments into the basin.
7. Encroachment of flood plains due to growth of population is also causing heavy damage though the flood is not so high. Sufficient area should be left in order to allow the flood water flow into the sea safely.This particular cause is an important human factor.Such that there is no flood zone planning for the coastal area of eastern ghat region.
8. The flow of Brahmani River is also adding to the flood in Baitarani River in the down stream.
   

The most flood affected blocks

• Anandapur
• Dasarathpur
• Korei
• Bari
• Jajpur
• Binjharpur
• Rajkanika

Alternate flood prevention strategy

• As per the coastal zone regulatoryAct, participatory flood zone mapping should be carried out &an implementable plan should be prepared.
• There should be dialogue between upstream & downstream stake holder to address the issue with mutual cooperation & contribution.
• Community level disaster contingency plan to be prepared to encounter any such further calamity.

Vulnerability to Flood

Flood is a regular phenomenon in the Baitarani basin and its inhabitants live with constantsfear of loss to life and property. Even a two-day rain in July this year made it overflowed its banks affecting 140,000 people in 220 villages of Jajpur and Bhadrak districts. There are also at least two other cases embactment breaching and marooning in this year inflicting massive loss to life and property1. Apart from the long pending construction of dam at Bhimkund and proposed other measures like river bed exacavation and construction of embankment etc. in the deltaic region, there remain an unaddressed needs of addressing the land use issues in the upstream, on which, till date no serious thoughts or efforts have yet been directed.

Environmental flow and River protection

The Salandi basin is drought prone due to the erratic trend of monsoon in September-October. For provision of irrigation and to control flooding in low lands, a dam intercepting 673 sq. km. of basin and a pick up barrage were built in 1970. This dam totally abstracts the peak flow and average monsoon and non- monsoon froom upper forested basin for consumptive use through irrigation. As a consequence there has been no spill to the lower basin thereby denying inudation irrigation to 50,000ha in the lower basin downstream of the command. With the monsoon flow below the dam drastically reducing and the non-monsoon flow dwindling, several pockets of wet land in the lower basin have dried up and can no longer sustain fish in particular and summer irrigation of cash crops and horticulture in general. The River below the dam has gone into distress as the channel has deteriorated. Consequently cccasional spill up to a maximum of 500 m3/sec causes over-bank flooding. Salinity incursion progressively into the dey river, lowering of ground water table and its contamination from the irrigation effluent, incapability of the river to convey even moderate flood discharge and loss of fish yield due to non-availability of the critical attracting flow in july are some of the adverse environmental impacts of the dam. Remidial measures to incorporate the environmental flow in the reservoir operation, rehabilitation of the river and its drainages and people’s participation have been suggested by some workers2 which need to be debated, weighed and integrated in the basin management plan.