The ambitious National River-Linking Project in India, aiming to connect 37 major river basins through 30 links, is raising environmental concerns. While the project promises to redistribute 174 billion cubic meters of water from 'surplus' to 'deficit' basins and generate 34,000 MW of power, experts warn of potential ecological disruptions.
Researchers from the Ashoka Trust for Research in Ecology and the Environment (ATREE) in Bengaluru have highlighted the risk of the project creating 'ecological highways' for invasive species. These species could spread to new, vulnerable regions, particularly in Northeast and peninsular India, threatening endemic species that are unique to individual river basins. The findings were published in Scientific Reports.
India's river basins, often isolated from each other, host many endemic species. The introduction of invasive species through river linking could jeopardize these native populations. Siddharth Agarwal, director-founder of the Veditum India Foundation, criticized the project, stating that it lacks a scientific basis and relies on the assumption that connecting wetter and drier regions will balance water distribution.
The study by ATREE indicates that basins in Northeast and peninsular India are particularly susceptible to biological invasions. The Southwestern Ghats, Kaveri, Krishna, Lower Ganga, and Brahmaputra basins are home to diverse habitats and complex ecological niches. These areas support both native and threatened species, as well as invasive alien species.
Aravind Neelavar Ananthram, the study's lead author and ATREE senior fellow, explained that invasive species are currently confined to individual basins. However, river connections could introduce new species and increase the vulnerability of native species unable to compete with these invaders. This aligns with global research suggesting that biodiversity hotspots are prone to accumulating invasive species, potentially turning into 'invasion hotspots'.
The Lower Ganga basin, hosting 13-15 invasive alien species, could become a significant invasion hotspot. This link is one of the project's most ecologically sensitive, posing a risk of extinction for threatened species. Water connections may also facilitate the spread of aquatic pathogens, disrupt fish migratory routes, and homogenize the unique biota of individual river basins.
Dr. Ananthram noted that fish in one basin might be immune to local pathogens, while species in other basins might not withstand these threats. Reduced water flow from transferring water between rivers could severely impact downstream biodiversity, potentially leading to the extinction of endemic species in lower reaches.
Critics like Agarwal question the project's efficacy in addressing water scarcity, particularly in regions like Bundelkhand, where the Ken-Betwa link is proposed. He argues that the project is more of a capital investment than an ecological solution. The Ken River, for instance, has ecologically valuable sand, but the link could lower water flow and sediment production, reducing biodiversity and possibly triggering a food chain collapse.
The project's implications extend beyond India. Currently, only 15 freshwater invasive species have been considered, but the total number, including terrestrial and marine systems, could be 350 to 400 species at various invasion stages. Developed economies like Australia and Europe have robust policies for managing invasive species, and India urgently needs a specific policy to regulate, manage, and control these species.
Incorporating evidence-based management of river basins into national infrastructure planning could provide ecological foresight. The health risks, biodiversity, wildlife, and economic costs of the project, especially for the agro-economy, farmers' livelihoods, and fisheries, demand urgent attention. While the government's intentions to address water deficits are commendable, development plans and policy decisions should consider ecological impacts, biodiversity, and people's lives.
