Abstract: A drainage system is located in a trench formed about the inner periphery of a foundation. The drainage system comprises a plurality of interconnected pipes, each positioned and pitched to allow water entering the pipes to flow to a collection site. The pipes comprise a longitudinal tubular member having a top wall with a central section containing a plurality of apertures. The top wall has a first sloping section which slopes from one end towards the central portion at a given angle and slopes from the other end towards the central portion at the same angle to enable any water directed on the top surface to flow into the apertures on the central portion of the pipe. The member contains a bottom wall and first and second side walls. A first side wall has a plurality of apertures and is positioned against the foundation wall. The second side wall is devoid of apertures as is the bottom wall. The side walls are each of the same height.