CLA CLA Grading & Drainage

Question 1

What is the minimum recommended slope for lawn areas to ensure positive drainage away from structures?

Accepted Answer

2%

Answer

1%

Answer

5%

Answer

10%

Question 2

A spot elevation of 102.50 is shown at the top of a swale and 100.00 at the bottom over a 50-foot run. What is the slope percentage?

Accepted Answer

5%

Answer

2.5%

Answer

10%

Answer

50%

Question 3

Which type of inlet is typically used at the low point of a parking lot to collect surface runoff?

Accepted Answer

Catch basin

Answer

Yard inlet

Answer

Curb inlet

Answer

Trench drain

Question 4

What grading technique uses a series of flat terraces separated by steep risers to manage slopes on hillsides?

Accepted Answer

Bench grading

Answer

Cut and fill

Answer

Swale routing

Answer

Berm construction

Question 5

On a grading plan, a dashed contour line typically indicates:

Accepted Answer

Proposed grade

Answer

Existing grade

Answer

Limit of work

Answer

Drainage swale

Question 6

What is the primary purpose of a drainage swale in landscape grading?

Accepted Answer

Convey surface runoff in a controlled channel

Answer

Retain stormwater on site

Answer

Increase infiltration only

Answer

Separate planting zones