Wednesday, June 27, 2012

Restore Indian Rivers for Water Security & Livelihood

Restoration of India’s rivers can help in attaining water security and promote sustainable livelihood, particularly for the deprived sections of the country’s large rural population.

Most rivers in the country have progressively degraded in quality due to rapidly increasing waste input from different sources, exacerbated with reduced flows, primarily due to large water diversion for multi-sector use.

Multiplicity of uses often conflicts with environmental concern. River restoration, with time dependant recovery, require committed long term approach, supported with hydrologic, quality of water and socio-economic studies to identify causes, contaminant sources and polluted stretches in order to plan compatible measures.

Restoration efforts face both natural and human induced constraints including varied hydro-climatic zones in the country, climatic vicissitudes, and anthropogenic actions producing undesirable situation.

Intensity and duration of rainfall varies widely in this vast country, from humid Meghalaya to arid Rajasthan, which has an unmistaken impact upon the flow regime. Major (12) and medium (48) rivers have been recognized, depending upon climatic condition, geographical locations and size of catchment, which reportedly contribute nearly 85 per cent of the total flow.

River courses, particularly perennial ones, may derive their water from multiple sources, such as catchment precipitation, snow/glacier melt, effluent streams and tributaries. Climatic changes can modify precipitation pattern, affecting runoff.

Ecological degradation can be inferred from enhanced biological oxygen demand (BOD), low levels of dissolved oxygen (DO), increase in toxic concentration of heavy metals, pathogens, load of organics including hydrocarbons and pesticides etc.

These changes could occur due to disposal of raw or partially treated sewage containing organic, inorganic and hazardous waste through various modes on river stretches. Open defecation, disposal of dead bodies and carcasses of animals, encroachments in flood plains, infrastructure affecting river course, agrarian activities and erosion are among other causes.

The polluted river waters create unfavourable habitat for the aquatic species such as fish, turtles etc and affect the livelihood of dependant communities, engaging in fisheries, boat / barge operation, cultivation, livestock rearing, among others. The use of degraded river water quality also affects human health, exposing vulnerable population to water borne diseases, besides endangering animal health as well as survival of aquatic biota.

Improvement in quantity and quality of river water and the ecological habitat therein, is attainable by applying available technology of waste containment, barring input along with waste dilution and dispersal by allowing sufficient natural flows for waste assimilation.

Waste generation e.g. municipal sewage and industrial effluents & emissions need to be curbed, as per existing guidelines. Agricultural activities including large use of irrigation water, overspreading chemical fertilizers, crop pesticides can contribute significantly in water quality decline. Waste can also travel from surface and shallow aquifer routes.

Although natural flow is impeded by dams, barrages, flood protection structures and river course modification etc, voluminous short-span precipitation and runoff during monsoon necessitates their storage in dam reservoirs for utilization during lean flow or dry period.

Uncontrolled massive load of sediments, debris and other land originated suspended and dissolved matters in flood waters needs to be regulated and minimized. Pollution loads from municipal, agricultural, industrial and other watershed sources including storm water, need proper evaluation for developing preventive and remediation methodology.

Concerted effort is required in implementing guidelines, policies and planned restorative actions together with sufficient financial infusion.

Among the corrective actions may include adopting conservation procedures, including bank stabilization, forestation and preserving surrounding wetlands and flood plains etc, managing storm water inflow to minimize watershed washout, systematic coverage of urban, semi-urban or rural settlements’ solid waste & wastewater collection and efficient operation of sewage treatment plants of sufficient capacity at anomalous locations, planned reuse of treated effluents on the land for non- domestic purposes with risk assessment, and  sensitizing riparian communities and the public at large in sanitation and hygiene for sustainable river utilization.

River use planning with emphasis upon the conservation of river water in all its usage should entail entire catchment, since partial approach is likely to be insufficient in a populous scenario.

The river management structure, therefore, may need a relook, in view of seemingly fragmented nature of water resources responsibilities undertaken by different agencies, both at state and Central levels.

An inclusive management strategy in cooperation with riparian states and stakeholder communities, may need to be established for each hydrological basin, some of which may even extend beyond state boundaries and national borders. Taking riparian communities into confidence, holistic planning should be able to integrate genuine ecological concern with sustainable development.

Knowledge-based social awareness campaign leading to habit change, respecting pollution bye-laws, formation of people’s interest groups are among more notables to be carried out by civic bodies/administration in coordination with people at local levels.

 (Author's comment: The article is developed on the premise that persisting river use problems in the river basin and their causes needed to be clarified for the purpose of developing and / or reviewing effective restoration programme. Most information is derived from different published and on line sources, including agencies data, observations and experience for which the author is truly indebted.)

By Dr Rashid Ali Khan former Water Resources Expert with Food & Agriculture Organization of the United Nations (FAO)@India Water Review

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