Asian Water Crisis & Good Practices
Two-fifths of the people in Asia’s cities do not have access to regular sources of water, let alone piped water. India is a glaring example. Quite exceptionally, we are confronted with the conundrum of insufficient water for an increasing urban population, receding groundwater levels and yet the peculiar incidence of unexpected flash floods.
Unplanned development – rapid growth in urban sprawl, unwieldy urban migration and densification, has led to unwarranted ground water extraction. Urban floods are due to sanctioning of construction zones on land earmarked for drains and floodplains, encroachments and use of impervious materials in building pavements, common areas etc. It is paradoxical that even cities short of water should suddenly face floods, or contrarily, places like Cherrapunji in Assam which has heavy rainfall should be short of good drinking water. Mumbai faces floods intermittently. In 2012 Beijing was flooded. A flood in Shanghai led Uber to change its logo from a car to a boat and to Chinese cities being described as those with “sea-views.”
Chennai was estimated to once have hundreds of water bodies. Wuhan in China used to have more than a hundred lakes, but it lost two-thirds of them to construction sites. In India, rapacious builders argue with regulators that a waterbody run dry deserves to be liberated for development in the master plan to meet the huge need for housing.
China learnt its lessons early. India has yet to wake up fully, even though it uses 25 per cent more water because of the hot weather. In 2013 Chinese President Xi Jinping initiated 30 “sponge cities,” to attract private partnerships for effective PPPs. Work on 16 sponge cities has commenced, targeting to reduce rainwater runoff by capturing 70 per cent of it through a grid of absorption channels and underwater tanks, cover rooftops with plants, create wetlands for rainwater storage and make pavements with permeable materials so that excess water may be stored. Water thus stored will be used for cleaning streets and firefighting. The water table under Beijing had been subsiding at an alarming rate because of pumping from wells. This has now slowed. The project has revived severely eroded ecosystems nearby which had earlier dried up.
Another initiative brought back more than a third of Beijing’s water supply from 1400 km away under the South-North Water Diversion Project from the Danjiangkou reservoir in the south from where water is brought through a linkage of canals and pipelines. Bhopal too has lifted water from the Narmada river 100 km away, to reduce its dependence on the Bhopal lake which used to cause problems every summer.
Along with policies for reuse and recycling, we will also have to ensure that municipalities value water. The strategies should be both revenue-fetching (metering systems have to be installed and appropriate tariffs fixed) and accountable. It is critical that only proven quality of materials and pipes be deployed for urban water systems. Municipalities are prone to making expedient choices as a result of which pipes keep bursting and leaking, thereby failing the best intended schemes.
Apart from decentralised rainwater harvesting, check dams, desalination technology, drip irrigation, crops that can tolerate saline water, solar panel research, greenhouses and hydroponic technology, it is also important to ensure that industrial and domestic water is treated and recycled to the best possible international standards. In Europe 80 per cent of water in industrial processes is recycled. In China the share is half that. In India it is negligible. Therein lies the way forward.
_20241002143912_original_image_37.webp)
_20241002142923_original_image_5.webp)
