Study warns of falling reservoir capacities

A study by Nashik-based Maharashtra Engineering Research Institute (MERI) has revealed that several large and medium-sized reservoirs in the state suffer huge sedimentation and may offer only around 30 per cent of their established capacity over the next 15 years.

The study, which included sedimentation analysis of 70 major and medium reservoirs in the country (22 from Maharashtra), has set alarm bells ringing in the state's water resources department.

Sources said that the issue will be discussed in the forthcoming session of the state legislature in Nagpur as four reservoirs mentioned in the study are in Vidarbha. The region already suffers from water scarcity and irrigation backlog.

According to the MERI study, some major reservoirs in the country, with gross capacity of 84,868 hectometres, are losing storage capacity at the rate of more than one per cent per annum.

"The observed sedimentation rate is generally 1.5 times to 3 times more than the designed parameter," the study observes.

Among the irrigation projects from Vidarbha are the Upper Wardha project in Amravati District, Bor in Wardha District, Lower Wunna and Totladoh in Nagpur District. The loss in live storage of these reservoirs ranges from 4.25 per cent at the Upper Wardha project to 0.46 per cent at Lower Wunna.

The study also notes that barring a few erosion control efforts, nothing much was being done for sediment management. It has stressed on the need to adopt integrated sediment management practices for long term use of reservoirs. The impact, it warns, may involve losing as much as 29.93 per cent of storage capacity by 2025.