Dams are small dams water escaped with gabion construction crucuk stone or wood / bamboo made in the groove ravine with a maximum height of 4m. Retaining the benefits of DAM is to control sediment and surface water flow from the Watershed (Catchment Area) in the upstream as well as increase the ground water level in the downstream.
Figure 30. Dam retaining gabion stone
The flow of water initially penetrate this stone gabion but ultimately expected sedimentation occurs at the top of the gabion gabion finally closes this sediment. Control dam is building a bigger and more powerful than the dams. Generally the control dam built with compacted soil or concrete form so that it can control floods. If the dams are built with stone gabion wire is impermeable to water. This control dam can be a big dam.
Figure 31. Dam controllers
levee
Dikes have another name levee, dike, embankment, which is a sort of slanted walls either artificial or natural, is used to regulate the water level. Usually made of soil and often are constructed parallel to the river or beach body. The word dike probably derived from the Dutch word dijk, where the construction of the embankment has happened since 12.Bangunan Westfriese Omringdijk century was completed in 1250, was established by connecting-nyambubngkan dikes that have been established previously.
While the Anglo-Saxon language, the word dic means digging trenches and form a pile soil on it. The main goal is made dike to prevent flooding on the outskirt of the river plains. This dike important role as dibberapa where often surface during a flood of the river water is higher than the surrounding area. However, the dike also control the direction of water flow of the river so it does not result in flooding.
Figure 34. Embankment
Dikes can also be found along the beach, where the sand dune beaches are not strong enough to withstand the waves. Dikes also be built along the edge of the lake or the beach in order to establish the limits of protection against a flooded area even at a given time may become a military protection. Levees could be the work of land permanently or only emergency construction, usually made of sand bags that can be erected quickly during the flood.
Mediterranean. Ancient civilizations of Mesopotamia and China is also building a levee system. Embankments along the river is one of the building or in the first and most important in our efforts to protect life and property in the community against the puddles caused by floods and storms (tidal wave). Dikes were built primarily with the construction of land fill, because the embankment is constantly bengunan very long and requires materials urugan huge volume.
Except for land, presumably it is very difficult to obtain any materials urugan for the construction of the embankment and soil material can be obtained from the furrows on either side of the alignment plan embankments or even may be obtained from the work of the normalization of the river, in the form of excavation widening of the river channel, which is usually held in conjunction with development dike. In the planning stage it is necessary diperhatiakan, that the results of the work of the normalization of the river can be used as an embankment material.
And land is a material that is very easy penggarapannya and after becoming very easy dike also adjust to the foundation soil layer support and also easy to adjust to a possible decrease uneven, so the improvement is caused by the decrease tractable. Furthermore, the land is a building material that is very stable and will not be broken for tens, even hundreds of years. If in some places the levees any damage, repairs are very easy and fast use of available land around the site of damage.
Figure 35. Building the embankment