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As part of a hazard mapping and evaluation study of the Kathmandu-Kakani area in the Middle Hills, Nepal, conducted as a United Nations/Unesco project, channel conditions at 43 stations on Thulo Khola and Ghatte Khola have been measured and peak discharges for the 1979 monsoon (a season of approximately normal precipitation) have been estimated. The results show that variations in the channels and the flows they carry in this tropical, high-relief area conform to the patterns established by other studies. This should allow hydrologic concepts and models that are derived from the long records and widespread studies of mid-latitude regions to be used in tropical mountains, where there are few direct observations. Flood hazards in the Kathmandu-Kakani area appear to be limited to those riparian zones which consist of constructed agricultural terraces. Damage to these terraces by channel expansion could provide a large influx of sediment to the fluvial system with consequent downstream siltation.

A century of study suggests many common characteristics in the geomorphic nature of high mountain areas. These include important structural influences in the landscape, usually on a variety of spatial scales, and contrasting climatic conditions (often confounded with vegetation distributions) which also exhibit a wide spatial variability. Most high mountain terrain also shows evidence of ancient erosion surfaces as well as that of past glacial action and other, less direct, consequences of late-Pleistocene environmental changes. The resulting landscape is one of high relief and highly variable potential energy. This is reflected in a history of recent erosion by large catastrophic events and a high potential for accelerated erosion where mountain terrain is impacted by man's activity. Such common characteristics suggest that mountain geomorphology be considered as a "regional" component within geomorphology.