1. It may also carry away soluble materials in the surface drainage waters. 2. Surface drainage must be allowed for precipitation to drain away from the structure.3. In the long run surface drainage can help to reclaim acid sulfate soils. 4. Checked surface drainage systems are also found in terraced lands used for rice. 5. The sewers were mainly for the removal of surface drainage and underground water. 6. Concrete rectangular drains were installed along the road for the road surface drainage system. 7. There are a number of surface drainage features in the vicinity of the stream. 8. For example, a city project to improve surface drainage would indirectly aid the urban poor. 9. Q . I had to have a sub-surface drainage system installed in my yard and around the foundation. 10. Surface drainage is generally good with almost all the rivers being seasonal, notably river Aya and river Be.
