Environmental Engineering Reference
In-Depth Information
Original contour
New Subgrade
Retaining wall
Fig. 4.3. If the original contour includes a rapid change in elevation, the use of a
retaining wall may be the only workable solution. (Drawing by R. Castro.)
to flood periodically, so a drainage system will probably be needed.
Properly designed drainage systems should ensure rapid removal of
water from the turf-grass root zone. Factors such as soil texture, topog-
raphy of the area and desired removal rate should be taken into consid-
eration. Small areas are often drained by perforated plastic tubes buried
below the surface. For large-scale projects, professional drainage design-
ers should be consulted. Perforated plastic tubing has become very
popular for subsurface drainage of turf-grass areas, but conventional
clay or cement drains should also be considered (Fig. 4.4). Clay drains
last for decades but are much more expensive to purchase and to install.
Fig. 4.4. Perforated plastic and clay drain pipes.
