Stormwater management

Question 1

Storm water that moves on the ground by gravity and flows into streams, rivers, ponds, lakes, and oceans

Answer 1

Surface runoff

Question 2

Storm water that infiltrate and moves through the soil both horizontally and vertically

Answer 2

Subsurface runoff

Question 3

A structure typically concrete block or precast concrete rings, 2.5 to 4 ft. in diameter, used to collect and divert surface runoff to an underground conduction system

Answer 3

Catch basin

Question 4

A general rule of thumb is that one catch basin may be used for each _________ sq. feet of paved surface

Answer 4

10,000

Question 5

A structure that allows surface runoff to enter directly into a drain pipe; unlike the catch basin, this does not contain a sump

Answer 5

Drain inlet

Question 6

A prefabricated structure, similar to a floor drain, that collects runoff from paved areas

Answer 6

Area drain

Question 7

Usually, one area drain is used for each _______ to ________ sq. feet of pavement

Answer 7

1000-2000

Question 8

A linear inlet structure used to collect sheet flow runoff in paved areas

Answer 8

Trench drain

Question 9

Manholes are often _________ ft. in diameter, made of concrete block, precast concrete, or fiberglass-reinforced plastic rings, which allows a person to enter a space below ground

Answer 9

4

Question 10

Any structure not classed as a bridge, which allows a water course to flow beneath a road, walk, or highway

Answer 10

Culvert

Question 11

An impoundment area constructed to collect storm runoff from a management system for the purpose of reducing peak flow and controlling the rate of flow; defined as having a permanent pool

Answer 11

Retention basin

Question 12

An impoundment area constructed to collect storm runoff from a management system for the purpose of reducing peak flow and controlling the rate of flow; normally dry

Answer 12

Detention basin

Question 13

An impoundment area or structure that slows the velocity of runoff in order to allow sediment particles to settle out

Answer 13

Sediment basin

Question 14

A constructed or natural drainage channel used to direct surface flow

Answer 14

Swale

Question 15

A trench filled with porous material which is used to collect and conduct surface runoff

Answer 15

French drain

Question 16

Drainage areas that are thousands of square miles

Answer 16

Watershed

Question 17

The runoff coefficient which represents a completely pervious surface from which there is no runoff

Answer 17

0

Question 18

The runoff coefficient which represents a completely impervious and wetted surface from which there is total runoff

Answer 18

1

Question 19

The number of years during which the design storm, or a storm exceeding it, statistically, may be expected to occur once

Answer 19

Storm frequency

Question 20

A storm with a frequency and duration for which the management system is designed; based on economics, environmental context, and the ultimate consequences should the system overflow

Answer 20

Design storm

Question 21

The time for water to flow from the hydraulically most remote part of the drainage area to the section under consideration

Answer 21

Time of concentration

Question 22

Typical pipe gradients for lawn areas

Answer 22

0. 1% (minimum)

1. 0% (maximum)

Question 23

The depth of water removed over the drainage area in 24 hours

Answer 23

Drainage coefficient