If four fires break out in a city of populationlakhs and if each hydrant has three streams and duration of each fire is four hours, the total quantity of water required, is

Turbidity of raw water is a measure of

By boiling water, hardness can be removed if it is due to

The maximum permissible nitrites in public water supplies, is

Time of concentration

Pick up the correct statement from the following :

The fire demand of a city may be worked out by

A high velocity of wash water is required for

Pick up the incorrect statement from the following regarding fire hydrants

Aeration of water is done to remove

Water supply includes

For determining the velocity of flow of underground water, the most commonly used non-empirical formula is

In distribution pipes, drain valves are provided at

The specific retention is least in case of

The yield of a rapid gravity filter as compared to that of slow sand filter, is

Corrosion of well pipes may not be reduced by

Surge tanks are used

B.O.D. of treated water should be

Corrosion of well pipes may not be reduced by

As per IS : 1172-water required per head per day for average domestic purposes, is

In slow sland filters, the turbidity of raw water can be removed only up to

Water supply includes

For determining the velocity of flow of underground water, the most commonly used non-empirical formula is

Biochemical Oxygen Demand (B.O.D.) of safe drinking water must be

Acidity in water is caused due to

Gravity conduits

Pick up the correct statement from the following :

The most ideal disinfectant used for drinking water throughout the world, is

Carbonates in water produce

Before constructing a dam, the factor to be considered for controlling sedimentation, is