Drainage is an important part of the construction project and plays an important role. Whether it should be for a shorter period of time of rain or more years in a rainstorm to reproduce, an effective surface drainage system design is very necessary, it can prevent water on the pavement, construction and property damage. At the same time reduce the possible environmental health. An effective drainage system can achieve the following functions:
· Reduce the area of water phenomenon
· To reduce the risk of falling and tire slippage due to slippery ground
· To protect the ground pavement and prolong the service life
·  Protection of fixed assets is not affected by flooding
· To reduce public discomfort in the rainy days