Rapid development in Malaysia with the construction of new towns may change the hydrologic and hydraulic characteristics of previously rural catchments. Flash flood and lower replenishment of groundwater may occur downstream of the new development areas as a result of increase in impermeable areas. Bio-Ecological Drainage System (BIOECODS) is an alternative urban stormwater management approach based on “control-at Source” concepts combining infiltration, detention storage as well as conveyance to delay flow. The main feature of BIOECODS is the use of subsurface drainage modules acting as both stormwater conveyor and attenuation agent. This report contains the study of drainage modules in order to determine their suitability and workability as well as to confirm the specifications of these components under local condition as implemented at the USM Engineering Campus, Nibong Tebal, Penang.

The objectives of this study are:

1. to test the hydraulic capacity of the drainage module

2. to check the water quality improvement capability of the drainage module

The results show that the drainage module should be designed as pipe flow and the resulting turbulence causes the DO level to increase with the distance as flow travels downstream.