Waste Water Engineering Multiple Choice Questions on “Storm Water Flow”.
1. Storm water can even occur as snow melts.
a) True
b) False
Answer: a
Clarification: Storm water, also spelled stormwater, is water that originates during precipitation events and snow/ice melts. Stormwater can soak into the soil (infiltrate), be held on the surface and evaporate or runoff and end up in nearby streams, rivers or other water bodies (surface water).
2. Which of the following is not a negative effect of storm water?
a) Volume
b) Runoff
c) Potential contaminants
d) Evaporation
Answer: d
Clarification: In developed environments, unmanaged storm water can create two major issues: one related to the volume and timing of runoff water (flooding) and the other related to potential contaminants that the water is carrying (water pollution).
3. Pollutants entering surface waters during precipitation events is termed ________
a) Runoff
b) Polluted runoff
c) Contaminated runoff
d) Water flow
Answer: b
Clarification: Pollutants entering surface waters during precipitation events is termed polluted runoff. Daily human activities result in the deposition of pollutants on roads, lawns, roofs, farm fields, etc.
4. Water is recycled into the atmosphere by vegetation through the process called ______
a) Evaporation
b) Evapotranspiration
c) Precipitation
d) Runoff
Answer: b
Clarification: Before development occurred most rainfall soaked into the ground and contributed to groundwater recharge or was recycled into the atmosphere by vegetation through evapotranspiration.
5. Stream erosion can be caused by excess ______
a) Precipitation
b) Evapotranspiration
c) Penetration
d) Transpiration
Answer: a
Clarification: Stream erosion can be caused by excess pollutants from the increased stormwater flow. It can further lead to weed invasion and alter natural flow regimes.
6. Storm water is a major cause of urban flooding.
a) True
b) False
Answer: a
Clarification: Storm water is a major cause of urban flooding. When the storm water overwhelms the capacity of drainage systems, urban flooding is caused.
7. Which of these is a single event?
a) Monsoon rain
b) Flash flood
c) Flood
d) Volcano eruption
Answer: b
Clarification: Flash flood is considered as a single event. It occurs for a short period of time without prior notice and with major after effects.
8. What is the amount spent in the UK every year because of flooding?
a) £250
b) £260
c) £270
d) £280
Answer: c
Clarification: According to the Federal Emergency Management Agency almost 40 percent of small businesses never reopen their doors following a flooding disaster. In the UK, urban flooding is estimated to cost £270 million a year (as of 2007) in England and Wales; 80,000 homes are at risk.
9. When was SWMM developed?
a) 1970
b) 1980
c) 1990
d) 2000
Answer: a
Clarification: SWMM was first developed in 1970 and has undergone four major upgrades since those years. It stands for Storm Water Management System.
10. Which year was the SWMM approved?
a) 2000
b) 2002
c) 2005
d) 2008
Answer: c
Clarification: SWMM 5 was approved FEMA Model Approval Page in May 2005 with this note about the versions that are approved on the FEMA Approval Page SWMM 5 Version 5.0.005 (May 2005) and up for NFIP modeling.
11. In which of the months does the maximum sewage flow occur in India?
a) March
b) May
c) July
d) September
Answer: c
Clarification: In India, the maximum sewage flow occurs in the month of June and July. This is because maximum precipitation occurs in these months. Hence the adequate storm water creates maximum sewage.
12. Which of the following runoff formula is correct w.r.t. Kuitchling formula?
a) I = 2567 / (t+20)
b) I = 2667 / (t+20)
c) I = 2676 / (t+10)
d) I =2867 (t+10)
Answer: b
Clarification: Runoff according to the Kuitchling formula is given by,
I = 2667 / (t+20) (for storm once in 10 years)
I = 3084 / (t+20) (for storm once in 15 years)
Where t is time (minutes) and I is precipitation (mm/hr).