Full Reservoir Level (FRL) is:

Explanation:

• The maximum elevation to which reservoir water surface will rise during normal operating conditions

• This defines the maximum water level that a reservoir is allowed to reach during standard or intended usage.

• It determines the design and operational limits of various hydraulic structures like spillways, gates, and power intakes.

• Beyond FRL, water is not normally stored, and any additional inflow is routed through spillways.

• The normal operating level in a reservoir

• FRL is considered the target water level during the reservoir’s routine operations.

• It ensures optimum storage for purposes such as irrigation, water supply, hydropower, and navigation.

• Operators aim to maintain this level to balance demand and storage without flooding or loss of utility.

• In seasonal reservoirs, water is typically stored up to FRL during monsoon and drawn down post-monsoon.

 Additional Information

Full Reservoir Level (FRL):

• The maximum elevation the reservoir water surface is allowed to reach during normal operations.

• Used for designing the capacity of the reservoir, penstocks, intake structures, etc.

Maximum Water Level (MWL):

• The highest level reached during design floods or emergency conditions, which may be above FRL.

• Determines the top of dam or freeboard design.

Dead Storage Level:

• The portion of the reservoir below the lowest outlet, not usable under gravity flow.

Live Storage:

• The volume of water stored between the dead storage level and FRL, usable for operational purposes.