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City of thirst

  • 14/03/1994

City of thirst THERE are water-scarce regions even within comparatively water abundant countries like India. One such region is Tamil Nadu, which has 9 per cent of the country"s population, but is endowed with less than 2 per cent of the nation"s water resources.

The availability of water in the state is temperamentally variable, particularly because of its slavish dependence on the vagaries of the northeast monsoon. Tamil Nadu is also among the most highly urbanised of states: 34.2 per cent of its population lives in cities and industrial growth has burgeoned in the major urban centres. The limited water resources of the state have to be shared between agriculture, industry and the voracious, rapidly growing needs of the urban populace.

Madras, Tamil Nadu"s capital and the largest city in south India, is home to about 5.4 million people. The city receives an annual rainfall of about 1,200 mm. But the cantankerous intemperance of the northeast monsoon ensures a city-wide thirst during its notoriously muggy summers. In the blessed years of relative normalcy, the per capita supply is about 78 litres per day; but in the lean periods, the water supply is often reduced to a miserly dribble -- on alternate days.

In such situations, households at the tail-end of the distribution system may not receive any water at all. To compensate, areas at the tail-end are provided water by tankers of the Madras Metropolitan Water Supply and Sewerage Board (Metrowater). It is believed that the long-term needs of the metropolis can be met only after the Telugu Ganga project -- which will divert flood waters from the Krishna river in Andhra Pradesh to Madras -- is completed. The waste water Madras spews out also causes serious pollution problems in the waterways and the coastal ecosystem.

A major institutional innovation in Madras was the establishment in 1978 of Metrowater, a separate water supply and sewerage board. Although the scope of the Act that created Metrowater covers the entire metropolitan area, its present jurisdiction is limited to the city and some industries on the city"s periphery.

Regulating water
Metrowater levies its own water and sewer tax and is equipped with the financial and technical capability to plan, implement and finance improvements to the system. Metrowater is also responsible for the regulation of groundwater, according to the 1987 Ground Water Act. The Madras Corporation retains jurisdiction on stormwater management and the Tamil Nadu Pollution Control Board on discharges of industrial effluents. The Public Works Department maintains the water supply reservoirs and is in charge of the water courses within the metropolitan area.

Since water in Madras is a premium commodity, it needs to be allocated in an efficient, equitable and ecologically sustainable manner. Efficient allocation would mean avoiding physical wastage during transmission and use, as would pricing the resource so that usage is optimised.

On the supply side, costs will have to be minimised by improving the infrastructure and the management of existing supplies. The stress will have to be on technical strategies such as reducing evaporation losses, regular checks on leaks in the distribution system and encouraging rainwater harvesting.

On the demand side, a bit of pragmatic harshness is required to optimise the use: charging the consumer the true value of water is clearly the most important factor here. In this connection, water meters will have to be rationalised. Further, the indiscriminate extraction of groundwater will have to be restricted by adopting appropriate regulatory measures, including special tariffs for electricity. The recycling and reuse of waste water by industries, municipalities and households can also go a long way in helping to rectify the scarcity.

At the same time, particular attention must be paid to slum dwellers and low-income groups who may not have the resources to invest in private wells or the wherewithal to purchase water from greed-driven private vendors.

Nonchalant disposal
The nonchalant disposal of municipal and industrial wastes into water bodies also has to be limited in line with their assimilative capacity, if sustainable use is to be achieved.

Madras" water scarcity has always been inevitability because the city is not located near any major river. The city is supplied with drinking water through three rain-fed reservoirs and various sources of groundwater on the urban periphery. Since the existing local sources are insufficient to meet the growing needs, the Telugu Ganga project has been initiated to transport water from the Krishna river in Andhra Pradesh to the city.

The first phase of the project is estimated to cost Rs 610 crore (at 1987 prices). It has also been estimated that the investment works out to about Rs 4.40 per 1,000 litres, whereas operation and maintenance costs will be around Rs 1.70 per 1,000 litres. The total cost to users will be around Rs 6.10 per 1,000 litres. In 1987, the delivered cost of water to households was estimated to be Rs 3.50 per 1,000 litres as compared to the direct municipal water tariff of Rs 2. Thus, the average cost of supplying drinking water could very well increase by 74 per cent.

Metrowater is, therefore, not only faced with an increasing marginal cost in enhancing the water supply, it also has to undertake projects that need to be financed and recovered through user charges. The bright side of the picture is that higher tariffs may also force users to be more careful with the faucet and the domestic water lines.

The low per capita supply provided by Metrowater forces households either to rely increasingly on deep bore wells or to purchase water from private vendors. All that the canny private vendors do is pump out groundwater from the coastal aquifer in south Madras and transport it by lorry tankers all over the city -- particularly to institutions and rabbits-warren apartment blocks. As a result, the price per tanker charged by vendors has risen steeply from Rs 250 to Rs 390 -- the equivalent of Rs 21 to Rs 32.50 per 1,000 litres. The unit cost of the supply by private vendors is naturally much higher than the most expensive public option, the Telugu Ganga Project. In other words, consumers are willing to pay a private seller much more than the tariff charged by Metrowater even though the sellers do not guarantee water of potable quality.

Even industries are willing to pay a higher price if they can be guaranteed uninterrupted supply. According to their self-serving calculations, the "opportunity cost" of water is the cost sustained when production has to be either halted or reduced due to the non-availability of water. They consider water to be as important as other raw materials and its economic value is gauged by the "opportunity cost" incurred due to a paucity of water. This is another way of suggesting that Metrowater can comfortably hike the tariff, as long as it can guarantee supply.

The other half
Supplying water at reasonable rates is, however, only the first half of any integrated water management system. The other half is the disposal and recycling of waste water. The sewerage system of Madras covers approximately 85 per cent of the city. Due to its flat topography, sewage has to be pumped through a complicated relay of some 60 pumping stations to five treatment plants on the urban periphery. Ironically, after the secondary treatment, the discharged effluent ultimately ends up polluting the waterways anyway.

A number of improvements have been effected following recommendations of Severn Trent International, a British consulting firm. The most promising development in re-using waste water is the agreement between Metrowater and two major industries -- Madras Refineries and Madras Fertilisers. Metrowater has agreed to supply secondary-treated sewage from the Kodungaiyur plant to the industries, which have set up tertiary treatment plants to improve the effluent quality to a level where it can be used for industrial cooling.

The economic value of this treated water will include the cost to Metrowater for initial treatment plus the cost of tertiary treatment incurred by the industries. A French consultant had estimated the selling price of the treated water to be Rs 10.50 per 1,000 litres (at 1988 prices).

Stormwater, collected through a network of drains that ultimately discharge into the waterways, can also meet certain needs. Metrowater maintains that it is impractical to collect stormwater run-off within the precincts of the city. However, voluntary organisations insist that the few remaining tanks in the periphery and the suburbs be retained to hold stormwater. A revival of some deficient temple tanks has also been attempted. The problem, however, is that urban stormwater run-off can be highly polluted and must be treated before use.

Since Madras is a coastal city, it is technically feasible to consider quenching thirst by desalinating seawater. However, the two promising technologies -- reverse osmosis and electrodialysis -- are expensive. The treated water will cost between Rs 40 to 50 per 1,000 litres (at 1988 prices). Despite this fat figure, desalination would be much cheaper than the present emergency system of transporting water by lorries from Neyveli. The fuel costs, the wear and tear on the lorries and the damage to highways would work out to be several times the cost of desalination.

Water for urban and industrial use can also be obtained by restricting water use in agriculture. Since irrigation consumes 70 to 80 per cent of the state"s water resources, even small improvements in agro-efficiency would release substantial quantities for non-agricultural utilisation.

Various industries have demonstrated their commitment to optimising the use of water by investing in tertiary treatment facilities. Unfortunately, the free supply of power to farmers has led to the extravagant use of groundwater for irrigating non-essential crops like casuarina. Apart from this anomalous situation, water management is, by and large, efficient.

The subsidy question
Although water is gratis for slum-dwellers and low-income groups, studies show that even the poor are willing to pay a nominal amount for drinking water, which is why it is not clear whether a full subsidy is warranted at all. At present, the growing suburban areas receive a paltry water supply and fare miserably in comparison with the city. In the interest of equitable allocation, Metrowater will have to expand its jurisdiction to the entire metropolitan area after the Krishna project is implemented.

Madras has a mixed record; it also has buckets of potential for integrated water management. However, greater attention needs to be paid in future to ecological sustainability in the management of water resources in the Madras metropolitan area. The happy paradox is that a strange melange of scarcity conditions and populist politics has led to a reasonably efficient and equitable allocation of water resources.

Paul P Appasamy is a fellow at the Madras Institute of Development Studies.

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