The most common and universal coagulant used in water works is

 

(A) magnesium sulphate

 

(B) calcium sulphate

 

(C) chlorine

 

(D) aluminium sulphate

Rainwater of the locality which flows in sewer is called

(A) subsoil water

(B) storm water

(C) combined sewage

(D) sullage

Which one of the following is not surface water?

(A) from natural spring

(B) from natural lakes

(C) from reservoir storage

(D) from river diversion

A dam constructed to store water during floods and release is gradually later is known as

(A) rigid dam

(B) detention dam

(C) diversion dam

(D) storage dam

Vertical wells provided along the banks of a riverbed to draw ground water in dry season are known as

(A) artesian wells

(B) infiltration wells

(C) tubewells

(D) open wells

Which one is not the effect of presence of iron oxide in water

(A) causes toxic effect

(B) increases hardness

(C) increases corrosiveness

(D) causes red color

Temporary hardness of water is due to the presence of

(A) nitrates

(B) sulphates

(C) carbonates

(D) chloride

The suitable method of forecasting population for a young and rapidly increasing city is

(A) graphical method

(B) incremental increase method

(C) geometrical increase method

(D) arithmetical increase method

Zero hardness of water is achieved by

(A) using excess alum dosage

(B) ion exchange method

(C) excess lime treatment

(D) using lime soda process

For trunk and out fall, the type of sewers generally used is

(A) circular shaped

(B) horse shoe shaped

(C) parabolic shaped

(D) standard egg shaped

For an area developed in haphazard way, the type of layout of water distribution system preferred as

(A) radial system

(B) ring system

(C) grid iron system

(D) dead end system