First of all, the importance of understanding and designing seepage control for a civil engineering project is a building, especially the basement structure might undergo detrimental effect due to the water movement in the soil beside the structure or under the structure. The groundwater may enter the structure which cause the leaking of the structure through the wall or floor. The causes of the leaking of the basement is the hydrostatic pressure. The water table varies widely with its location and it is affected by proximity to the bodies of water. The bad weather, such as heavy rain, will cause the water absorption by the soil and promote the soils become saturated. Thus, the elevation of the water table could rise and it creates hydrostatic pressure towards the structure when the water table rise to the region below or beside the structure. The hydrostatic pressure could force the groundwater flow into the structure which create leaking of the basement. In addition, the lateral pressure generally is caused by the expansion of the soils which will damage the structure and the leaking would occur. In this case, the understanding and designing of the seepage control is much important to protect the structure to undergo damage. The example of the controlling of seepage is the installation of interior perimeter drainage system. This kind of drainage system is installed beneath a basement to help reducing the water table by collecting the groundwater and pump it out before it rises high enough to leak into the basement.
Next, all the embankment or dam around the world are all dealing with the seepage.
Figure 1.1.2 (b) Dam
Since the embankment or dam have seepage, it is important for civil engineers to understand and design the seepage control in order to prevent the occurrence of the internal erosion and the instability. The significant of seepage problems is excessive seepage in the embankment or dam would lead to a problem with the safety of the embankment or dam if it is not treated properly. Seepage can create the force and pressure which will lead to create a new or enlarge existing seepage pathways and thus making the embankment or dam is breached. Suffusion and piping is the phenomenon due to the internal erosion. Suffusion will cause the fine particles are eroded through the voids between the larger particles by the seepage flow, leaving behind the coarse skeleton. Meanwhile, piping is the phenomenon occur due to the progressive erosion and transportation of soil particles along a flow path. Therefore, the seepage control is extremely important for civil engineers to understand and design so that these particular problems can be prevented.