Storm Drainage Flashcards
Learn about storm drainage system requirements and best practices. (25 cards)
True or False:
Storm water shall be drained into sewers intended for sanitary drainage.
False
Fill in the blank:
Subsoil drainpipe shall be surrounded by not less than ______ inches of gravel, slag or crushed rock.
4
Fill in the blank:
The minimum discharge pipe size for a subsoil drain sump is ______ inches.
1 1⁄2
Fill in the blank:
A subsoil drain sump discharge pipe is permitted to discharge onto a concrete splash block with a minimum length of ______ inches.
24
What is the minimum pipe size for an open areaway drain for a surface less than 100 square feet?
2”
Which of the following is not an approved system for draining roof areas of a building?
a. subsoil drain
b. roof drain
c. gutters
d. vertical conductors
a. subsoil drain
Fill in the blank:
An open-sided roof or scupper shall be sized to prevent ______.
excessive ponding on the roof
True or False:
No trap is required for storm drainage pipes that are connected to a sewer that only carries storm water.
True
Fill in the blank:
Roof drains shall have _____\____ strainers.
domed
Fill in the blank:
The size of building storm drains shall be based on the ______.
Area of the roof
Fill in the blank:
Where a vertical side wall drains onto a roof, for one wall ______ percent of the wall area shall be added to the roof area figures.
50
Fill in the blank:
Where a pump continuously discharges into a storm drain, 1 GPM of discharge shall be equal to ______ square feet of roof area.
24
Which of the following is not a conditional requirement for controlled- flow roof drainage?
a. Water from a 25 year storm shall not be stored on the roof for more
than 24 hours.
b. Not less than two drains shall be installed in roof areas of 10,000
square feet or less
c. Scuppers shall be provided in parapet walls.
d. Scupper openings shall be not less than 3 inches high.
d. Scupper openings shall be not less than 3 inches high.
Fill in the blank:
A water test on a storm drainage system shall be kept in the system for not less than ______ minutes.
15
What is the pipe size for a vertical storm drain in a location with 4 inch per hour rainfall and a roof surface area of 10,500 square feet?
6”
What is the pipe size for a vertical storm drain in receiving a maximum flow of 535 gallons per minute?
6”
What is the size for a horizontal rainwater pipe with a slope of 1/4” per foot in a location with 3 inch per hour rainfall and a roof surface area of 40,000 square feet
12”
What is the size for a horizontal rainwater pipe with a slope of 1/2” per foot in a location with 1 inch per hour rainfall and a roof surface area of 11,500 square feet?
4”
What is the size for a horizontal rainwater pipe with a slope of 1/4” per foot with a maximum flow rate of 200 gallons per minute?
6”
What is the size for a storm drain gutter with a slope of 1/16” per foot in a location with 3 inch per hour rainfall and a roof surface area of 2,000 square feet?
8”
What is the size for a storm drain gutter with a slope of 1/2” per foot in a location with 4 inch per hour rainfall and a roof surface area of 2,000 square feet?
6”
Which of the following is not an option for subsoil drain piping?
a. solid wall pipe
b. perforated pipe
c. open-jointed drain tile pipe
d. none of these
a. solid wall pipe
What is the pipe size for a vertical storm drain in receiving a maximum flow of 120 gallons per minute?
4”
What is the size for a horizontal rainwater pipe with a slope of 1/8” per foot in a location with 2 inch per hour rainfall and a roof surface area of 9,500 square feet?
6”
