Mangaluru: An unplanned development path adopted by “unscrupulous decision-makers” is threatening the ecologically sensitive regions in the Netravathi river basin in the State, according to a study report released by a team of researchers from the Indian Institute of Science (IISc), Bengaluru, here on Friday.

The report titled “Carrying capacity of Netravathi river basin based on the ecological sensitiveness” was released by Energy and Wetlands Research Group (EWRG), Centre for Ecological Sciences (CES), IISc, at Alva’s College during the pre-lake 2018 conference jointly organised by the IISc and Alva’s Education Foundation.

It said that river diversions, hydro electric projects, coastal reservoirs, commercial plantations, unscientific tourism, etc., would cause irreplaceable loss of rich biodiversity in the river basin. Referring to the river basin, it said that Netravathi having a catchment area of 4,409 sq km covers 11 taluks in Chikkamagaluru, Hassan, Kodagu, Dakshina Kannada and Udupi districts.

It originates in Bangrabalige valley, Yelaneeru Ghat of Kudremukh in Chikkamagaluru district. The basin is part of the ecologically fragile Western Ghats, one among the 35 global hotspots of biodiversity. “It is the lifeline of Dakshina Kannada region supporting the enormous population with rich resource base and diverse cultures,” it said.

The 203-page report from T.V. Ramachandra, co-ordinator, EWRG-CES, Bharath Setturu and Vinay S., researchers, said that rivers/streams in the ecologically sensitive regions should not be diverted or manipulated as that would affect the water retention capability of the catchment area and ground recharge potential. It would affect the sustenance of water in the streams and affect the downstream users’ right to adequate freshwater.

The report said that of the 433 villages in the basin, 111 are in ecologically sensitive region (ESR) I followed by 69 villages in ESR II, 119 villages in ESR III and 134 villages under ESR IV.

“Persistence of the endemic (rare, threatened, etc.,) species in ESR I and ESR II calls for serious attention from conservationists and decision-makers to initiate programmes immediately for conservation,” the report said. The report assumes significance in view of the ongoing Yettinahole diversion project in the Netravathi basin.

Earlier, a group of researchers from IISc, led by Mr. Ramachandra, had, in a report, questioned the State government’s estimation of the project yielding 24 tmcft of water for diversion to parched districts. The group said that only 0.85 tmcft of water could be diverted from the project. The group had warned that the project would lead to water scarcity in Hassan and Dakshina Kannada and would not benefit Chikkaballapur, Kolar and Tumakuru districts.