CLARB - Council of Landscape Architectural Registration Boards Grading, Drainage, and Stormwater Questions and Answers

Question 1

A landscape architect is designing a stormwater management system for a commercial property.
The primary goal is to manage peak runoff rates by temporarily holding water and releasing it slowly.
The system should be dry between storm events.
Which of the following is the most appropriate solution?

Accepted Answer

A detention basin

Answer

A retention basin

Answer

A French drain

Answer

A bioswale

Question 2

When grading a site to direct surface water away from a building foundation, what is the generally accepted minimum slope?

Accepted Answer

2% (1/4 inch per foot)

Answer

0.5% (1/16 inch per foot)

Answer

1% (1/8 inch per foot)

Answer

5% (5/8 inch per foot)

Question 3

A client wishes to address soggy lawn conditions caused by a high water table and subsurface water movement. They want an underground solution that will intercept and redirect this water away from the problem area. Which drainage system should be recommended?

Accepted Answer

A French drain

Answer

A vegetated swale

Answer

A catch basin

Answer

Permeable pavers

Question 4

A path has a starting elevation of 102.5 feet. The path is 80 feet long and has a constant slope of 2.5%. What is the elevation at the end of the path?

Accepted Answer

100.5 feet

Answer

102.0 feet

Answer

104.5 feet

Answer

105.0 feet

Question 5

Which of the following stormwater management techniques is a form of green infrastructure designed to slow, filter, and infiltrate surface runoff through a shallow, vegetated, and gently sloped channel?

Accepted Answer

A bioswale

Answer

A dry well

Answer

A trench drain

Answer

An underground storage tank

Question 6

During the design of a large parking lot, the landscape architect must incorporate a stormwater feature that not only manages runoff but also improves water quality and provides aesthetic and habitat benefits. The feature should maintain a permanent pool of water. What is the most suitable option?

Accepted Answer

A retention pond

Answer

A detention pond

Answer

An infiltration trench

Answer

A channel drain

A landscape architect is designing a stormwater management system for a commercial property.The primary goal is to manage peak runoff rates by temporarily holding water and releasing it slowly.The system should be dry between storm events.Which of the following is the most appropriate solution?

A landscape architect is designing a stormwater management system for a commercial property.
The primary goal is to manage peak runoff rates by temporarily holding water and releasing it slowly.
The system should be dry between storm events.
Which of the following is the most appropriate solution?