Why in News?

• Hydropower projects that do not comply with the Centre’s ecological flow notification could face closure.

Highlight:

• The Natural Flow Regime is the characteristic pattern of a river’s flow quantity, timing, and variability.
• Environmental flows/ ecological flows are the acceptable flow regimes that are required to maintain a river in the desired environmental state or predetermined state.

What is Ecological flow Notification?

• Power producers generally hoard water to create reserves to increase power production.
• The Centre’s ecological flow notification, 2018 mandates that project developers ensure a minimum supply of water all through the year.
• The notification came into effect in October 2018 and gave companies three years to modify their design plans, if required, to ensure that a minimum amount of water flowed during all seasons.
• The e-flow notification specifies that the upper stretches of the Ganga — from its origins in the glaciers and until Haridwar — would have to maintain: 20% of the monthly average flow of the preceding 10-days between November and March, which is the dry season; 25% of the average during the ‘lean season’ of October, April and May; and 30% of monthly average during the monsoon months of June-September.
• It will apply to the upper Ganga River Basin starting from originating glaciers and through respective confluences of its head tributaries finally meeting at Devaprayag up to Haridwar and the main stem of River Ganga up to Unnao district of Uttar Pradesh.
• In September 2019, the government advanced this deadline, from October 2021 to December 2019. This was after it tasked the Central Water Commission (CWC) to ascertain actual flows and the amount of water present in the river through 2019.

Details:

• The Central Water Commission (CWC) will be the designated authority and the custodian of the data, and will be responsible for supervision, monitoring, regulation of flows and reporting of necessary information to the appropriate authority as and when required and also take emergent decisions about the water storage norms in case of any emergency.
• Power projects will be assessed by the CWC quarterly for compliance after December 2019.
• Projects that are not compliant will have to face closure.