Correct option is B
Storm water inlets Storm water inlets are the openings in the pavement, which collect surface runoff & direct it into the storm sewer system. These are used to prevent flooding & protect streets from damage.
Types of Manholes:
(a) Straight - Trough Manholes: When there is a change in the size of sewer, the soffit or crown level of the two sewers should be the same.
(b) Drop Manholes: To connect the high level branch sewer to the low level main sewer by vertical dropping pipe.
(c) Junction Manholes: Built at every junction of two or more sewer
(d) Flushing Manhole: When it is not possible to obtain self-cleaning velocities due to flatness of the gradient. It is essential that some form of flushing device be incorporated. Flushing manholes are located at the head of sewers or at points where the grade changes significantly. They are used to flush out sediment & debris, which may have accumulated in the sewer system.
Catch basin - It allow the strom water to enter the sewer by eliminating the silt, grit, etc. at the bottom of the basin. It helps to maintain the efficiency of the sewer system & prevent blockages.
