Context: Recently, Uttar Pradesh government has told the Centre that it has planned to fix the minimum environment flow for the polluted stretches of at least six rivers.

• The state government has planned to regulate the E-flow for polluted stretches of Saryu, Hindon, Ramganga, Betwa, Ghaghara and Rapti rivers.

About the Background

• So far, Ganga is the only river in the country for which E-flow has been fixed by the Centre.
• In October 2018, the then Ministry of Water Resources, River Development and Ganga Rejuvenation — now Ministry of Jal Shakti — had issued a notification, fixing the E-flow for Ganga.

About E-flow

• E-flow is the minimum limit of flow required to maintain a river in the desired environmental state.
• It will ensure that the river has at least the minimum required environmental flow of water even after the river flow gets diverted by projects and structures.
• The river flow would be diverted for purposes like irrigation, hydropower, domestic and industrial use etc.
• It is an important step taken towards maintaining the uninterrupted or Aviral flow of the river.
• The compliance of minimum environmental flow is applicable to all existing, under-construction and future projects. 
• The mini and micro projects which do not alter the flow characteristics of the river or stream significantly are exempted from these environmental flows.