Stormwater Test 2 UPDATED ACTUAL
Questions and CORRECT Answers
What is WQV - CORRECT ANSWER - Water quality volume is the treatment volume
required to remove a significant percentage of runoff pollution load
What is the maximum contributing flow length for a downspout disconnect? - CORRECT
ANSWER - 75'
What is the minimum slope to drain turfgrass? - CORRECT ANSWER - 2%
What range of slopes are required for the downspout disconnect? - CORRECT ANSWER -
2%-6%
What kind of flow occurs at the end of the downspout? - CORRECT ANSWER - sheet
flow
What is a level spreader? - CORRECT ANSWER - a device that allows for water to pass
over land at a level depth and to create sheet flow (like a baby berm)
What is the design criteria for a downspout disconnect? - CORRECT ANSWER - 1) max.
contributing flow length of 75'
2) min. length of pervious flowpath below the disconnect of 15', equal or greater than the flow
path
3)max. rooftop area per downspout of 2,500 sf
4) max slope of pervious area below downspout of 6%
5) sheet flow character below downspout disconnect
6) downspout outlet orientation is directed away from the building
, What is the equation used to find the volume contributing to a downspout disconnect? -
CORRECT ANSWER - Roof Area (sq. ft) x ([rainfall inchesx95%]/12)=CuFt
What percent of TSS is required to be removed according to the GSWMM standard? -
CORRECT ANSWER - 80% of TSS
What does TSS stand for? - CORRECT ANSWER - Total Suspended Solids
What is turbidity? - CORRECT ANSWER - the quality of being cloudy or thick with
suspended solids, suspended solids settle out eventually
Why is it important to capture TSS/polluted runoff before it reaches streams and lakes? -
CORRECT ANSWER - to preserve our water resources and aquatic habitats
How do we achieve 80% TSS removal? - CORRECT ANSWER - we teat a portion of all
storms, we intercept and treat ALL of the runoff from 85% of the storms that occur within in the
average year
What percent of Georgia storms are 1.2 inches or less? - CORRECT ANSWER - 85%
What percent of storms are greater than 1.2 inches (in georgia)? - CORRECT ANSWER -
15%
How many inches of rain is considered a 1-year storm in Georgia? - CORRECT
ANSWER - 3.2 inches
What does it mean when we say "1 year storm event"? - CORRECT ANSWER - it means
that there is a 99% probability that it will occur in any year
Are 1-year storm events considered Water quality storms? - CORRECT ANSWER - No,
because a 1-year storm is 3.2 inches and we aren't required to treat storms of that magnitude
Questions and CORRECT Answers
What is WQV - CORRECT ANSWER - Water quality volume is the treatment volume
required to remove a significant percentage of runoff pollution load
What is the maximum contributing flow length for a downspout disconnect? - CORRECT
ANSWER - 75'
What is the minimum slope to drain turfgrass? - CORRECT ANSWER - 2%
What range of slopes are required for the downspout disconnect? - CORRECT ANSWER -
2%-6%
What kind of flow occurs at the end of the downspout? - CORRECT ANSWER - sheet
flow
What is a level spreader? - CORRECT ANSWER - a device that allows for water to pass
over land at a level depth and to create sheet flow (like a baby berm)
What is the design criteria for a downspout disconnect? - CORRECT ANSWER - 1) max.
contributing flow length of 75'
2) min. length of pervious flowpath below the disconnect of 15', equal or greater than the flow
path
3)max. rooftop area per downspout of 2,500 sf
4) max slope of pervious area below downspout of 6%
5) sheet flow character below downspout disconnect
6) downspout outlet orientation is directed away from the building
, What is the equation used to find the volume contributing to a downspout disconnect? -
CORRECT ANSWER - Roof Area (sq. ft) x ([rainfall inchesx95%]/12)=CuFt
What percent of TSS is required to be removed according to the GSWMM standard? -
CORRECT ANSWER - 80% of TSS
What does TSS stand for? - CORRECT ANSWER - Total Suspended Solids
What is turbidity? - CORRECT ANSWER - the quality of being cloudy or thick with
suspended solids, suspended solids settle out eventually
Why is it important to capture TSS/polluted runoff before it reaches streams and lakes? -
CORRECT ANSWER - to preserve our water resources and aquatic habitats
How do we achieve 80% TSS removal? - CORRECT ANSWER - we teat a portion of all
storms, we intercept and treat ALL of the runoff from 85% of the storms that occur within in the
average year
What percent of Georgia storms are 1.2 inches or less? - CORRECT ANSWER - 85%
What percent of storms are greater than 1.2 inches (in georgia)? - CORRECT ANSWER -
15%
How many inches of rain is considered a 1-year storm in Georgia? - CORRECT
ANSWER - 3.2 inches
What does it mean when we say "1 year storm event"? - CORRECT ANSWER - it means
that there is a 99% probability that it will occur in any year
Are 1-year storm events considered Water quality storms? - CORRECT ANSWER - No,
because a 1-year storm is 3.2 inches and we aren't required to treat storms of that magnitude
