25-09-2014, 03:20 PM
Abstracts: A passage running underneath, especially a passage for pedestrians or vehicles, or both, crossing under a railroad, road, etc. is known as Underpass. The underpass is very rarely adopted in bridge construction but recently the underpass is being used for traffic movement. Drainage in an underpass is always a problem because it’s almost always impossible to align the slope of the underpass drainage with that of the main drain outside the underpass (whose level will be higher than the underpass). The problem becomes worse when the underpass is located at a site which is topographically also a naturally depressed zone. In such an area the tendency of water from all the surrounding catchment area is to flow towards that depression with no escape route in sight. There are various methods to avoid waterlogging, some of them are: I. Diversion of the drainage pipeline around underpass. II. Rain water harvesting. III. Laying of storm water pipelines. IV. Construction of storage tank.