The urban water crisis

Transcription

1 The urban water crisis Most cities suffering from severe water scarcity;water conflicts Urban flooding after every monsoon Declining groundwater tables; Urban water bodies polluted and dying Water supply (no of hours) Early 1980s Early 1990s Early 2000s Chennai Vizag Hyderabad Source: World Bank Bangalore

2 The urban water crisis why? Growing urban population Grown almost five times in five decades from 1951 (62.44 million) to 2001 (286.08). In 1951, there were 5 Class I cities with over 1 million population, and in 2001 there were 35 such cities. Urban water demands are higher. Growing industrial & commercial use Growth of million plus cities

3 Urban water paradigm: fuelling crisis Bring water into the city storage, diversion, pipe, pump, treat from further and further away. Flush and carry the waste out of the city pipe, pump, divert, treat further and further away. It is capital intensive; It is resource intensive; Relies on government subsidising costs; The state can subsidise some but not all. Creates divide between the rich and poor in a city; and between cities and rural areas.

4 Demand vs Supply Delhi Mumbai Hyderabad Bangalore Kolkata Chennai Offical demand Supply before leakage loss CPHEEO demand Supply after leakage loss

5 Cities import water from far flung rural areas Cities, which are richer and powerful, take water from rural hinterlands. Chennai brings water from Veeranam, Mumbai from Vaitarna and Bhatsa, Hyderabad from Manjira and Nagarjuna dams and Jodhpur from the Indira Gandhi canal, each of them about 200 km away from the respective city.

6 Case of Delhi Delhi search for water. Looking further and further away. Depriving rural areas of water Thousands of crores spent to transport water & treat Using wastefully. Polluted water bodies

7 Depleting groundwater levels NIUA says: Over 21 % of urban water demand is met from groundwater CGWB says: overexploited or dark zones in the country are tripling every decade.

8 Delhi

9 The face of urban water crisis Distance from the sea coast in m The red lines mark the distance from the sea to which saltwater had intruded in the respective years: In about than 30 years, the seawater has intruded inwards for almost 20 m

10 Insatiable want for water Cities want more. In all cities plan is to increase the availability of water to meet the needs of all. DELHI Per capita availability 211 lpcd 2011 Master plan targets 363 lpcd

11 Cities create conflicts Political costs Conflicts between rural and urban peoples; conflicts within cities Inequities in water supplied Inequities in sanitation facilities Within the city, disparity between the rich and the poor Rich drink bottled water; poor use the filthy rivers for drinking, bathing, cooking

12 Cities create conflicts 2004 > Water availability LPCD Search turns to Veeranam Lake. (235 km away) Completed June 2004 Tamil Nadu Lake dry at peak demand time (Feb. to July) Solution: Dig borewells to augment supply Result? Water table plummets. Farmers agitate

13 Cities are inefficient in their use of water Huge distribution losses in water supply between %. 20 per cent of the water used for drinking, cooking; 80% for bathing, washing and flushing down the toilet. Cost recovery difficult because of huge distribution losses. Increased pollution in source water adds to cost of treatment. Cannot invest in efficiencies and clean water for all.

14 Cities do not recover costs City Production cost Rs/kl Water charges Rs/kl Delhi Mumbai Jodhpur Indore Bangalore

15 Unsustainable investments Planning Commission working group for 11 th Plan Funds needed for full coverage of estimated urban population of 366 million by 2012 = crore For sewerage and sanitation = crore For urban drainage = crore Total = crore Outlay up until 10 th plan = crore Is this sustainable?

16 Citizens take action Rainbow Drive, a newly developed private colony in Sarjapur Road in Bangalore No municipal supply or sewage treatment Borewell supply; own STP Over the years borewells dried up (3/5) Started rainwater harvesting from stormwater drains; individual plots (recharge wells 55); storage tanks Supply from groundwater 2 borewells (after RWH) Water charges based on costs of RWH + cost of STP

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18 Case of RWH in Hyderabad Enough water! Crystal clear!

19 The urban agenda sewage management Sewage systems does not exist in our cities only 15% of sewage generated is treated Where they exist: Sewage pipes are not connected to treatment plants; sewage still pollutes rivers, streams Where there are ST plants, often there is no power or sometimes funds to run the plants; sewage still pollutes rivers and streams. Where sewage is treated, treated sewage gets mixed with untreated sewage; river is still polluted. Sewage-excreta biggest challenge for modern India

20 The urban agenda sewage management All sewage treatment plants built in river cleaning programmes as grants/loans/pu blic investment. Massive subsidy to sewered populations.

21 Maths of national excreta Waste-maths: How much is generated, how much is collected, how much is treated? 2006 CPCB estimated sewage from class I and II cities = 33,200 mld Existing sewage treatment capacity : 6,190 mld (18% of sewage) Sewage actually treated: 4,400 mld (72% of capacity created) Gap: 28,800 mld of sewage Only 13.5% of sewage generated actually treated

22 Treatment: River cleaning started in 1985 Objectives were: Interception and diversion of sewage Sewage treatment plants (STPs) Low cost sanitation works to prevent open defecation Electric crematoria River front works like bathing ghats Plantation, public awareness etc

23 Indian rivers: massive programme for clean up 90 per cent of Ganga Action Plan money spent on sewerage and STPs; 2 per cent on sanitation

24 Drainage exists; but does not work. Drainage does not exist; does not work Cannot transport waste to the STP. Large parts of the city does not have officialunderground drainage system Large parts of the city lives in unauthorisedillegal colonies; Sewers in bad state defunct, silted, settled Delhi: 5,600 km of drains in city; 130 km of trunk sewers; in poor state Agra: 45 km of sewers; only in 14 km functional

25 No assimilative capacities in our rivers Freshwater withdrawals are reducing the flow in the rivers Cities aspire to draw more and more freshwater to augment its water supplies Cities are worried about water not about their waste Waste not treated goes into water of others cities have to invest in cleaning water (Agra chlorine). Can t clean then they look for new source

26 Challenge: Take the waste out of wastewater Polluted water contains nutrients that belong to the land. Farmers and governments spend crores of rupees on nitrogen and phosphorous which the domestic wastewater contains Using sewage for farming is one of the best ways of using wastewater. Sewage farm in Kolkata wetlands where city s farming is undertaken In Israel, 70% of domestic wastewater is treated to irrigate the country s hectares of agricultural lands. Deep reservoirs and lagoons biologically treat wastewater

27 Revive and protect water bodies Hyderabad 679 water bodies within 30 km 111 have a surface area of over 10 hectares each, with average of 2 m depth. They can store 164,756,000 cubic metre (m 3 ), which is more than the water that the Krishna Project is expected to supply.

28 Reduce use: be water efficient Educate to reduce wasteful use Provide incentives for water efficient fixtures: Move from 15 litre flush systems to 6-7 litres systems. Better still move to ecosanitation Incentivise taps that waste less water Introduce rating system for water effciient fixtures and water efficient buildings

29 Future urban hydrology? Capturing rainwater from macro and micro catchments Rooftop water can be used for drinking Groundwater recharge Recycle wastewater : Can be used for toilet flushing, gardening, urban irrigation Look at dry sanitation options Use less water. Do not be wasteful

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31 Threats to the water bodies Water pollution: sewage, industrial effluent, garbage dumping Encroachment of the lake bed. Change in landuse pattern of the lake bed Degradation of catchment, siltation Unplanned development in the catchment area Mining from the lake bed

32 Destruction Threats to the of water bodies Bangalore city had 51 lakes in early 1970s and by the end of the century, this number plummeted to a mere 17, of which only 14 can be considered to be alive. In Hyderabad, there were 932 water bodies in 1973 which were reduced to 834 in The Ahmedabad collector on directions from the high court listed 137 lakes in the city but also said that over 65 had been already built-over.

33 Kunds of Aravalli ancient origins Surajkund was built by the Tomar kings more than 1000 years ago. Badkhal Lake was a natural lake formed at the base of two hillocks. These lakes existed for thousands of years till very recently when they could not withstand the impacts of large scale mining. These two lakes were largely fed by rainwater and needed the catchments to be maintained in order to retain good water levels throughout the year.

34 Fighting degradation of waterbodies First petition filed in 1985 to ban mining in Aravallis Government forced to look into it. Studies showed devastating impacts of mining on the ecology and water bodies. Showed mining pits reached below the aquifer; massive evaporation of groundwater due to exposure of groundwater. Fractured governance: Files moving between tourism ministry, forest dept and irrigation dept. Court orders ban on mining. Despite court order licenses continued to be issued.

35 Aravallis undermined