Patent ID: 8182174

Claim:
A drainage system comprising: at least one first drainage pipe to be disposed within the ground and including a single-piece first porous pipe wall that has a top open end to be disposed proximate to the ground surface for entry of surface water thereinto, a bottom open end for extending to a level distant from the ground surface, and a plurality of first through holes disposed between said top and bottom open ends to permeate the surface water into adjacent soil areas; and at least one second drainage pipe transversely connected to said first drainage pipe, and including a single-piece second porous pipe wall that has two opposite open ends, and a plurality of second through holes disposed between said two opposite open ends of said second porous pipe wall to permeate the surface water into adjacent soil areas; wherein said single-piece second porous pipe wall further has an upper wall portion, and a lower wall portion facing and extending below said upper wall portion, said upper wall portion having a blocking member that blocks solid particulates from entering said second porous pipe wall through said second through holes; wherein said blocking member includes a lining layer that covers an inner surface of said upper wall portion and that is made from a waterproof material; wherein said second porous pipe wall is formed with a semicircular cross-section, said upper wall portion being arcuated, said lower wall portion being flat.