Question

The surcharge storage in a dam reservoir is the volume of water stored ________________

(a) between the minimum and maximum reservoir levels

(b) between the minimum and normal reservoir levels

(c) between normal and maximum reservoir levels

(d) below the minimum pool level

I have been asked this question during a job interview.

My doubt stems from Capacity and Area Elevation Curves of a Reservoir Site topic in section Reservoirs and Dam Reservoirs Planning of Irrigation Engineering

Answer 1

The correct answer is (c) between normal and maximum reservoir levels

To explain I would say: Surcharge storage is uncontrolled storage which is the volume of water stored between the normal pool level and the maximum pool level. It is that portion above the crest of the dam’s spillway which cannot be regulated.