*5.4.3 Dam Lake which was previously used in sewage*

It was found that most of them obstructed the movement of water and were exposed to the intensity of evaporation and high temperature in the region, with a decrease in the level of water in general in the area surrounding the body of the dam, and desertification of most of the land in front of it. This is due to the increased risk of floods caused by the phenomenon of sedimentation behind dams. The lack of access to the sea has led to the deterioration of the marine environment, where many marine organisms, including benthic fish and crustaceans that feed on the sediment, have been affected [19] (**Figure 15**).

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*Flood Risk and Vulnerability of Jeddah City, Saudi Arabia*

*DOI: http://dx.doi.org/10.5772/intechopen.82073*

**5.5 Some ways to reduce the risk of floods**

**Figure 15.**

*Dam Lake for sanitation.*

in times of extreme necessity.

which any plan is developed.

prior scientific studies.

The valleys have devastating effects on urban facilities:

lack rainwater drainage channels and floods to regulate flow.

be provided around residential areas, farms, and installations.

• Treatment of the source of the problem of sedimentation in dams.

places where runoff water can be exploited.

• Establishment of dams of various types and forms (surface and subsurface) on the main valleys or on the tributaries, especially in the places of danger revealed by hydrological studies, to reduce the runoff in the valleys and the use of water

• Rationalization of the construction of protection dams in major cities, which

• Establishment of industrial channels to transfer runoff from hazardous areas to

• Cladding process using appropriate materials on the sides of roads or barriers to

• Geomorphological maps that illustrate the locations of risk and safety places on

• Creation of different land use schemes away from hazardous areas, based on

• Benefit from this study in applying its proposals to similar areas in Saudi Arabia.

**Figure 14.** *Floodwater channels.*

**Figure 15.** *Dam Lake for sanitation.*

*Recent Advances in Flood Risk Management*

pleting a peripheral drainage.

*5.4.1 Completion of floodwater channels*

El Assla and Mreikh (**Figure 14**).

Hableen, Daghbj, and Bariman.

*5.4.2 Construction of medium and trench dams*

*5.4.3 Dam Lake which was previously used in sewage*

the sediment, have been affected [19] (**Figure 15**).

Ghlil, and Khumra.

ces, networks, GIS, and expert systems.

water.

○ Sealing water leaks in buildings by installing water leakage barriers, processing sandbags, cracking, network packaging (electricity, gas, telephone, and water), closing ventilation outlets under flood levels, and using internal pumps to pump

○ Facilitating the return to normal mode by creating the surroundings of the buildings, using thermal insulation of water, placing the electrical panels outside the water level, establishing a separation network for the flooded places, and com-

• Application of environmental assessment methods including checklists, matri-

• The northern channel of the direction of sailing for the drainage of the Valley of

• The central channel for the drainage of the valleys of Karaa, Mreikh, Ghia, Om

• The southern channel of the drainage of the valleys of Kawes, Osheer, Methweb,

It was found that most of them obstructed the movement of water and were exposed to the intensity of evaporation and high temperature in the region, with a decrease in the level of water in general in the area surrounding the body of the dam, and desertification of most of the land in front of it. This is due to the increased risk of floods caused by the phenomenon of sedimentation behind dams. The lack of access to the sea has led to the deterioration of the marine environment, where many marine organisms, including benthic fish and crustaceans that feed on

**5.4 Measures taken in previous periods to address the problem of floods**

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**Figure 14.** *Floodwater channels.*
