Automated design flood estimation for highway drainage

Good surface drainage is one of the basic needs for strength and durability of any finished pavement. Although the deteriorating action of water has been known for centuries, significant advances in this direction have been made in recent past. Previous field surveys, tests of interstate freeways, state highways, airfield runways, taxiways and aprons in various regions spread all over the world, for the last three decades, have greatly strengthened the need for proper drainage of pavements. The study of past records shows that in the case of culverts, the failure-rate is upto 90% solely on account of hydrological failure. Therefore, it becomes clear that the success of both of the aforesaid steps depend on a detailed and precise analysis of hydrological data to get a dependable estimate of peak discharge. If this is not done, the pavement may have to face serious deterioration and even failures due to the occasional, unconsidered and unaccounted for flood. This problem takes significant proportions in tropical countries like India and especially in its northern plains where topography of the area is not very uniform and soil strata is rather soft.