Rule Curve of a River

Rule Curve of a River

Subject – Governance

Context – Mullaperiyar dam: TN violated rule curve, says Kerala minister

Concept –

• A rule curve or rule level specifies the storage or empty space to be maintained in a reservoir during different times of the year.
• Here the implicit assumption is that a reservoir can best satisfy its purposes if the storage levels specified by the rule curve are maintained in the reservoir at different times.
• It decides the fluctuating storage levels in a reservoir.
• The gate opening schedule of a dam is based on the rule curve.
• It is part of the “core safety” mechanism in a dam.

In case of Mullaperiyar dam, the Supreme Court asked Kerala and Tamil Nadu to abide by the water level of 139.5ft notified by the expert committee in Mullaperiyar dam.