CO Stormwater Systems Contractor
Exam Practice Questions And Correct
Answers (Verified Answers) Plus
Rationale 2027 Q&A| Instant
Download Pdf.
1. Which Colorado stormwater management practice is primarily
intended to reduce runoff volume by allowing precipitation to
infiltrate into the underlying soil rather than immediately entering a
conveyance system?
A. Detention basin
B. Riprap channel
C. Infiltration basin
D. Concrete-lined ditch
C. Infiltration basin
An infiltration basin temporarily stores stormwater and allows it to
infiltrate into the surrounding soil, thereby reducing runoff volume and
helping restore groundwater recharge.
2. During construction, what is the primary purpose of installing a
stabilized construction entrance?
,A. To increase the infiltration rate of the site
B. To prevent sediment and mud from being tracked onto public roads
C. To provide permanent drainage for the completed project
D. To increase vehicle access speed
B. To prevent sediment and mud from being tracked onto public roads
A stabilized construction entrance provides a firm, aggregate-covered
access point that helps remove sediment from vehicle tires and reduces
tracking onto adjacent streets.
3. Which stormwater pollutant is most directly associated with
exposed soil on an active construction site?
A. Sediment
B. Chlorine
C. Dissolved oxygen
D. Carbon dioxide
A. Sediment
Exposed and disturbed soil is highly susceptible to erosion, making
sediment one of the most significant pollutants generated by
construction activities.
4. What is the primary difference between a detention basin and a
retention basin?
A. A detention basin is designed to permanently hold water
B. A retention basin generally maintains a permanent pool, while
detention storage is normally temporary
,C. Detention basins cannot have emergency spillways
D. Retention basins are used only for erosion control
B. A retention basin generally maintains a permanent pool, while
detention storage is normally temporary
Detention facilities primarily store stormwater temporarily and release
it at a controlled rate, whereas retention facilities are generally
designed to retain water for longer periods and may maintain a
permanent pool.
5. Which erosion-control measure is generally most appropriate for
protecting a newly seeded soil surface from raindrop impact and
sheet erosion?
A. Concrete pavement
B. Temporary mulch
C. Steel trench plates
D. Permanent fencing
B. Temporary mulch
Mulch protects exposed soil from direct raindrop impact, reduces runoff
velocity, and helps retain moisture while vegetation becomes
established.
6. What is the primary function of a silt fence installed along the
downslope perimeter of a disturbed construction area?
A. Divert all stormwater around the project
B. Filter and slow shallow sheet flow so sediment can settle
, C. Replace a storm sewer
D. Increase the velocity of runoff
B. Filter and slow shallow sheet flow so sediment can settle
A silt fence is intended primarily for sediment control by slowing shallow
runoff and promoting deposition of suspended soil particles before they
leave the disturbed area.
7. Which condition most strongly indicates that a silt fence has been
installed improperly for its intended purpose?
A. The fence is placed along a contour
B. The bottom edge is properly trenched into the soil
C. Concentrated runoff is directed against the fence
D. Sediment accumulates on the upslope side
C. Concentrated runoff is directed against the fence
Silt fences are generally intended for shallow sheet flow rather than
concentrated flows, which can bypass, undermine, or collapse the
barrier.
8. When constructing a temporary diversion swale, what is one of the
most important design considerations?
A. Eliminating all vegetation from the swale
B. Providing adequate capacity and stable side slopes for anticipated
runoff
C. Making the channel as narrow as possible
D. Preventing all water from reaching the site outlet
Exam Practice Questions And Correct
Answers (Verified Answers) Plus
Rationale 2027 Q&A| Instant
Download Pdf.
1. Which Colorado stormwater management practice is primarily
intended to reduce runoff volume by allowing precipitation to
infiltrate into the underlying soil rather than immediately entering a
conveyance system?
A. Detention basin
B. Riprap channel
C. Infiltration basin
D. Concrete-lined ditch
C. Infiltration basin
An infiltration basin temporarily stores stormwater and allows it to
infiltrate into the surrounding soil, thereby reducing runoff volume and
helping restore groundwater recharge.
2. During construction, what is the primary purpose of installing a
stabilized construction entrance?
,A. To increase the infiltration rate of the site
B. To prevent sediment and mud from being tracked onto public roads
C. To provide permanent drainage for the completed project
D. To increase vehicle access speed
B. To prevent sediment and mud from being tracked onto public roads
A stabilized construction entrance provides a firm, aggregate-covered
access point that helps remove sediment from vehicle tires and reduces
tracking onto adjacent streets.
3. Which stormwater pollutant is most directly associated with
exposed soil on an active construction site?
A. Sediment
B. Chlorine
C. Dissolved oxygen
D. Carbon dioxide
A. Sediment
Exposed and disturbed soil is highly susceptible to erosion, making
sediment one of the most significant pollutants generated by
construction activities.
4. What is the primary difference between a detention basin and a
retention basin?
A. A detention basin is designed to permanently hold water
B. A retention basin generally maintains a permanent pool, while
detention storage is normally temporary
,C. Detention basins cannot have emergency spillways
D. Retention basins are used only for erosion control
B. A retention basin generally maintains a permanent pool, while
detention storage is normally temporary
Detention facilities primarily store stormwater temporarily and release
it at a controlled rate, whereas retention facilities are generally
designed to retain water for longer periods and may maintain a
permanent pool.
5. Which erosion-control measure is generally most appropriate for
protecting a newly seeded soil surface from raindrop impact and
sheet erosion?
A. Concrete pavement
B. Temporary mulch
C. Steel trench plates
D. Permanent fencing
B. Temporary mulch
Mulch protects exposed soil from direct raindrop impact, reduces runoff
velocity, and helps retain moisture while vegetation becomes
established.
6. What is the primary function of a silt fence installed along the
downslope perimeter of a disturbed construction area?
A. Divert all stormwater around the project
B. Filter and slow shallow sheet flow so sediment can settle
, C. Replace a storm sewer
D. Increase the velocity of runoff
B. Filter and slow shallow sheet flow so sediment can settle
A silt fence is intended primarily for sediment control by slowing shallow
runoff and promoting deposition of suspended soil particles before they
leave the disturbed area.
7. Which condition most strongly indicates that a silt fence has been
installed improperly for its intended purpose?
A. The fence is placed along a contour
B. The bottom edge is properly trenched into the soil
C. Concentrated runoff is directed against the fence
D. Sediment accumulates on the upslope side
C. Concentrated runoff is directed against the fence
Silt fences are generally intended for shallow sheet flow rather than
concentrated flows, which can bypass, undermine, or collapse the
barrier.
8. When constructing a temporary diversion swale, what is one of the
most important design considerations?
A. Eliminating all vegetation from the swale
B. Providing adequate capacity and stable side slopes for anticipated
runoff
C. Making the channel as narrow as possible
D. Preventing all water from reaching the site outlet
