7-726: 35°17′N 136°39′E / 35.28°N 136.65°E / 35.28; 136.65 The Kiso Three Rivers ( 木曽三川 , Kiso Sansen ) are the three major rivers that make up the alluvial plain area of the Nōbi Plain of Japan . The three rivers are the Kiso River , the Ibi River and the Nagara River . Given their location, they are sometimes referred to as the Nōbi Three Rivers (濃尾三川 Nōbi Sansen ). At various points downstream,
14-508: Is Japan's largest national government park which straddles Aichi , Gifu and Mie Prefecture . The center of the park is located in the city of Kaizu in Gifu Prefecture. From the park, visitors can see each of the three rivers, as well as Ise Bay and the mountains surrounding the Nōbi Plain . Alluvial plain An alluvial plain is a plain (an essentially flat landform ) created by
21-491: The United States National Cooperative Soil Survey (NCSS), defines an "alluvial plain" as "a large assemblage of fluvial landforms (braided streams, terraces, etc.) that form a low gradient, regional ramps along the flanks of mountains and extend great distances from their sources (e.g., High Plains of North America)". Use of "alluvial plain" as a general, informal term for a broad flood plain or
28-449: The deposition of sediment over a long period by one or more rivers coming from highland regions, from which alluvial soil forms. A floodplain is part of the process, being the smaller area over which the rivers flood at a particular time. In contrast, the alluvial plain is the larger area representing the region over which the floodplains have shifted over geological time. As the highlands erode due to weathering and water flow,
35-403: The margins of the flood channel, will be eroded by lateral stream erosion, local rainfall, and possibly wind transport if the climate is arid and does not support soil-holding grasses. These processes, over geologic time, will form the plain, a region with little relief (local changes in elevation) yet with a constant but slight slope. The Glossary of Landform and Geologic Terms , maintained by
42-586: The rivers flow together and then separate again, often leading to flooding and water damage. Since the Edo period , much work has been done to plan dykes and other structures that will help control the rivers. In the late part of the 19th century, rulers of the Satsuma domain worked with the Dutch engineer Johannis de Rijke to help with flood control of the area. Kiso Sansen Park (木曽三川公園 Kiso Three Rivers Park , Kiso Sansen Kōen )
49-479: The sediment from the hills is transported to the lower plain. Various creeks will carry the water further to a river, lake , bay , or ocean . As the sediments are deposited during flood conditions in the floodplain of a creek, the elevation of the floodplain will be raised. As this reduces the channel floodwater capacity, the creek will, over time, seek new, lower paths, forming a meander (a curved path). The leftover higher locations, typically natural levees at
#245754