Self-Test D-3.7 Sub-soil Drainage Systems

Complete Self-Test D-3.7 and check your answers.

1. What is the term given to the scientific study of the movement, distribution, and management of water on Earth?
   1. Hydrology
   2. Hydronomy
   3. Hydroscopy
   4. Hydroelectricity

    

2. Which one of the following is not a true statement when moisture is removed from the ground around footings by installing subsoil drains?
   1. Ponding is reduced.
   2. The water table is lowered.
   3. Soils become waterlogged.
   4. Soil strength is stabilized or increased.

    

3. What was often the shape or profile of the outside of short lengths of drain tile?
   1. Triangular
   2. Octagonal
   3. Hexagonal
   4. Pentagonal

    

4. How much space was there intended to be between lengths of vitrified tile drainage pipe?
   1. [latex]\tfrac{1}{16}[/latex] in. to [latex]\tfrac{1}{8}[/latex] in.
   2. [latex]\tfrac{1}{8}[/latex] in. to [latex]\tfrac{1}{4}[/latex] in.
   3. [latex]\tfrac{1}{4}[/latex] in. to [latex]\tfrac{1}{2}[/latex] in.
   4. [latex]\tfrac{3}{4}[/latex] in. to 1 in.

    

5. How many degrees apart are the perforations on common PVC perforated pipe?
   1. 45°
   2. 60°
   3. 90°
   4. 120°

    

6. According to the BC Building Code, where should the top of the pipe used for footing drains be located?
   1. Below the bottom of the floor slab or ground cover of the crawl space
   2. Above the bottom of the floor slab or ground cover of the crawl space
   3. Below the bottom of the footing
   4. Above the bottom of the footing

    

7. What type of layer protects the drain rock and perforated pipe from becoming plugged with fines from the soil?
   1. Plastic film
   2. Newspaper
   3. Linen
   4. Geotextile fabric

    

8. What is the term for an excavated hole in the ground that is filled with drain rock and used as a terminal for storm or subsurface water?
   1. Well
   2. Dry well
   3. Wet well
   4. Water well

    

9. What is the term that is sometimes used to describe a trench; perforated pipe; clean, washed rock; geotextile fabric; and backfill intended for subsurface drainage?
   1. Ditch drain
   2. French drain
   3. Canadian drain
   4. Below-surface drain

    

10. What is the name given to a drain that might be installed at the foot of a rock face and that is intended to intercept and channel away water that would pond at the base of the slope?
    1. Rockface drain
    2. Channel drain
    3. Curtain drain
    4. Slope drain

     

11. What is the term given to the process of creating horizontal holes underground that water can flow through to get to a trench drain?
    1. Moling
    2. Tunnelling
    3. Chambering
    4. Crosshatching

     

12. What is the average depth of the pipe in a trench drain used as the main drain associated with the question above?
    1. 300 mm (1 ft)
    2. 600 mm (2 ft)
    3. 1,200 mm (4 ft)
    4. 1,800 mm (6 ft)

     

Answer Key: Self-Test D-3.7 is on the next page.