BENGALURU: Ecologists and environmentalists have pointed out that linking of rivers will lead to severe environmental implications. Prof T V Ramachandra, Energy and Wetlands Research Group, Centre for Ecological Sciences, IISc, feels that river-linking projects at a mega scale will spell doom for the regional economy with scarcity of water and food, which will impact sustainable living. Excerpts:
What is your view of the government’s announcement on the river-linking project?
The proposed river-linking projects at a mega scale are neither technically feasible, environmentally sound, nor economically viable. Altering the natural course of rivers will be disastrous and will affect sustenance in the region. The prevalence of invasive species leads to erosion of native aquatic biodiversity and will impact local people’s livelihood. Hence, before mega scale projects are proposed or taken up, we need social and ecological auditing of earlier projects. For example, the Telugu Ganga project was implemented in the 1980s to supply 15 tmcft of water from Krishna basin to Chennai. But after implementing it, Chennai has got a maximum of 3.8 tmcft of water. Lack of accountability and transparency regarding failed projects has encouraged decision-makers to opt for such proposals, which will benefit only a small section (a nexus of consultants, contractors and engineers) of society while depriving water and food security to a majority of the local population in the river basins.
Why do you think the government is making such an announcement now?
The country has been facing a severe water crisis due to mismanagement of water resources in the last century. Water has become an emotional issue. Every politician/government tries to capitalise on it and falls prey to the illogical and unscientific proposals mooted by a section of society to capitalise on the water-scarce situation.
Will it open a Pandora’s box, as there are many inter-state disputes?
Certainly. Such projects which lack scientific rigour or scrutiny will pave the way for disasters. Mismanagement of river basins will lead to the decline of water retention capability of watersheds, leading to conversion of perennial streams to intermittent or seasonal streams, which will further aggravate the situation of water scarcity leading to more inter- and intra-state conflicts.
When there are issues like the Mahadayi and Mekedatu, what do you think will happen with this?
Conflicts in society will always benefit decision-makers. Hence, such issues are kept alive. There were some interventions in Malaprabha basin earlier that led to the watershed losing its ability to retain water, which has contributed to water scarcity. Instead of rectifying the problem in the Malaprabha catchment, a proposal cropped up to divert Mahadayi water, contributing to further degradation of both river catchments.
The Mekedatu project leads to the submersion of about 4,700 hectares of forests, including Cauvery wildlife sanctuary (submerges 65% of sanctuary spatial extent) with numerous endemic species of flora and fauna. Instead of a decentralised option of water harvesting, such senseless projects are pushed. For example, Bengaluru city (spatial extent of 740 sqkm), with annual rainfall of 700-850 mm, gets about 15 tmcft of water while the city requires about 18 tmcft of water. The best option is rainwater harvesting at an individual (rooftop) and community (through lakes) levels. To meet local water demand, rejuvenate lakes, enhance water storage capacity and improve groundwater recharge. Currently, 45% of Bengaluru’s water needs are met from groundwater sources, and this will be the best and most viable option.
Is it worth investing so much in river-linking projects?
Natural capital accounting and valuation of ecosystem services reveal that forests provide services — Provisioning services (tangible benefits) worth Rs 2.19 lakh per hectare per year, Regulating services worth Rs 3.31 lakh per hectare/year, Cultural services worth Rs 1.05 lakh per hectare/year and the total ecosystem supply value of forest ecosystem is Rs 6.56 lakh per hectare/year. So, with this value, against what the government is talking of investing, one can understand that it’s not worth the investment. The forest assets NPV (Net Present Value) is Rs 80 billion. Considering the worth of the forest ecosystems, it is prudent not to disturb the vital ecosystem.
Is there an alternative?
There are solutions like decentralised water harvesting through lakes and tanks, treatment of waste water, watershed programmes through engineering and ecological treatment which will enhance the water retention capacity of the catchment. All these are implementable and cost-effective, which enhances job opportunities.