山坡地野溪河道經常因為土石流或高含砂水流之衝擊下，造成大量土石淤積，若無適當土石清淤，很容易於再次遭遇颱風時，造成下游生命及財產之損失，因此需藉由適當之評估機制，從大量野溪中篩選出最可能產生災害地點，進行後續之土石清淤。本研究以宜蘭縣所屬山坡地為例，建立土石清淤野溪篩選方法；首先以土石流潛勢溪流為主，依照保全對象；發生潛勢及警戒值為依據，選出 10條土石流潛勢溪流；隨後透過崩塌地面積；保全人口數及土石流影響範圍為依據，選出四條土石流潛勢溪流；最後再加入六條已執行清淤之野溪，總共 10條野溪，進一步透過土砂淤積量；交通運輸及環境敏感區位分析，找出其中最需要進行土石清淤之野溪，未來或可提供為相關單位篩選土石清淤河段之依據。

Massive sediment deposit usually happens when debris flow or high sand flow occurs in hillslope. If there is not any treatment such as sediment dredging, the loss in life and property usually arise during the period of typhoon. Therefore, a suitable assessment method, which can be used to select the most possible place of disaster in the future, is necessary for the follow-up sediment dredging. This study establishes the assessment method of sediment dredging for Hillslope using the example of Yilan county, Taiwan. Firstly, three criterions including protection aspect, potential possibility, and emergency value are employed to select 10 potential streams from the potential streams database of debris flow. Secondly, another three new criterions consisting of landslide area, protection population and the influence area of debris flow, are then used to choose 4 potential streams from 10 potential streams in first time. Finally, above 4 potential streams and another 6 streams, which are executing sediment dredging, are totally compared to find the most requirement stream of sediment dredging by the index analysis of sediment volume, traffic transportation, and environmental sensitive location. The assessment method can be used to select the potential stream of sediment dredging for relational organization..