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Narrative Description of the Project:

Hydrologic and hydraulic study for wadi Dima Attaiyn Road S-18A in Al Mudabgha. The road is located in Ash Sharqiyah Region near the Road No.25 that is running along the main Wadi Dima. Along the road alignment one main catchment has been determined and the resulting 50 years return flood calculated. Two options have been studied: box culverts and bridge. The Consultant?s investigation has led to the conclusion that 6 box culverts (4x4) are not functional for a 50 years return period storm because they can?t guarantee the design constraint (All-Weather Road) being the flow total head over the road surface. Culverts functionality is also at risk if we consider the high flood velocities, the channel steepness (0.03) and the presence of boulders on the wadi bed. Even adopting suitable protections against scouring, erosion and debris the culvert option will not be in accordance with the Highway Design Manual (2010) unless it is requested by the Client to reduce the road functionality. Taking into account the above mentioned reasons the Box Culverts Option is not recommended. The Consultant recommends the Bridge Option as it fulfills with the requirement ?All- Weather Road?. Taking into account that the wadi width is about 30 meters, it could be possible to construct a bridge without piers, without narrowing the wadi section and obviously eliminating the problem of scouring. Bridge functionality is higher than culverts.

Description:

1) Hydrology study
2) Hydraulic study
3) Drainage structure concept design
4) Detailed report and drawings submission