The purpose of this study is to analyze the urbanization of Nagano City with regard to the Olympic Winter Games, in particular from the viewpoint of the conversion of farm land to the public land use. The findings are summarized as follows:
In 1991, the International Olympic Committee selected the City of Nagano as the site of the 18th Olympic Winter Games in 1998. From that time, high-speed transportation networks such as the Hokuriku (Nagano) Sinkansen (Bullet Train) or the Joshinetsu Highway were constructed in Nagano City. Of course Olympic facilities such as the Olympic Village and access roads going to these facilities and the like were constructed. But these projects did not incorporate urban planning on a long-term basis.
Most of the urban infrastructure in Nagano City was constructed on agricultural land. As a result, the area of noushin-chiiki (agricultural land protected from development) which had been about 25, 000ha in 1989, decreased by 1% during the period from 1989 to 1998. The area of nouyouchi-kuiki (specific areas within agricultural land protected from development) which had been about 7, 700ha in 1989, decreased by 5% during the period from 1989 to 1998. As a result, it will be difficult to convert agricultural land (especially nouyouchi-kuiki) to urban infrastructural land use in Nagano City in the future.

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At the request of the Philippine government, Japanese experts are now plans for a flood control system for the Cagayan River being made. Severe flooding in the plain made the agricultural land very poor. If the flooding situation could be controlled, the Philippine's economic conditions would be vastly improved.
Recognizing that little data concerning the flooding of the river and plain currently exist, the authors set about creating a geomorphological survey map of the area.
The authors collected the base maps and Landsat images to make a provisional geomorphological map in Japan. Then, in April 2000, the authors visited the Philippines to conduct fieldwork using the latest available aerial photographs.
The Cagayan River flows between the Cordillera Central Mountains in the west and the Sierra Madre Mountains in the east and pours into the Babuyan Strait near the city of Aparri.
The valley plain in the middle reaches of the river consists of higher alluvial terraces and lower alluvial plain. Both higher terrace and lower plain have following geomorphological elements, i. e., natural levee, back marsh, etc.
In an extraordinary flooding, not only lower plain but also highly terraces were inundated as shown in Fig. 3.
Furthermore, the river are frequently and quickly changing the course, and three former river courses or oxbow lakes currently exist. Eastward shifting of the river in 1960, 1970 and 1979 made these former river courses.
The authors have devised two provisional flood control plans, as follows.
1) Short-cut plan: A new river channel would be cut in the easternmost part of the plain to create a shortcut for the meandering course.
The geomorphological characteristics such as the area, average height, relief energy, velocity of the upheaval movement show the regional differences between the Cordillera Central and the Sierra Madre mountain ranges and the number and area of the branch rivers in the former range are larger than that of the latter. These factors show that the risk of land collapse in the Cordillera range is high and that the amount and size of the sand and gravel transported from the mountains are also larger than that of the Sierra Madre.
Shifting the river course from west to east in the valley plain is explained in sense an geomorphological viewpoint.
2) Construction of an embankment: The best way to protect the city of Tuguegarao and its vicinity from flooding is to construct an embankment. The embankment will be set on the edge of the highly alluvial plain. The location and scale of such an embankment could easily be determined by the geomorphologic map.
In the lower reaches, flood water levels would be decreased by constructing the shortcuts and several retarding reservoirs in the back marshes. Abandoned river courses could be used as retarding reservoirs. The usefulness of geomorphological map would be proved in the decision of location such retarding reservoirs.

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