Question

Which of the following statement is incorrect?

(a) Water can be withdrawn from any selected level of the reservoir using dry intake towers

(b) Intake towers have to be designed for the worst combination of hydrostatic wind earthquake and wave forces

(c) Dry intake towers are lighter in construction as compared to wet intake towers

(d) In dry intake tower, the water is directly drawn into the withdrawal conduit through the gated entry ports

I had been asked this question in a dream while sleeping

This intriguing question originated from River Intakes in section Pressure Conduits, Outlet Works through Dams and Rivers of Irrigation Engineering

Answer 1

Correct choice is (c) Dry intake towers are lighter in construction as compared to wet intake towers

The best I can explain: The water through the entry ports with gates is directly drawn into the withdrawal conduit in a dry intake tower. Dry intake towers is heavier in construction as it is subjected to additional buoyant forces even if the gates are closed. There are separate gate controlled openings for the conduit in a wet intake tower and openings are also made into the shaft.