The determination of the Deli watershed, Medan, North Sumatra, Indonesia as a critical watershed is because the critical land area is almost half of the total Deli River area, which will theoretically affect the sustainability of the land and water resources of the Deli watershed area. The watershed is a land area bounded by a natural boundary of topography that serves to accommodate, store, and drain the water received to the nearest river system which further leads to reservoirs or lakes or seas. the damage to agricultural land is increasing. This may result from erosion, water logging, accumulation of salts in saline areas, the accumulation of elements or compounds that are toxic to plants due to the use of chemical fertilizers and chemical drugs continuously every year. Deli land destruction is dominated by biophysical factors, especially land use, slope, landform, and rainfall in the upstream Deli sub watershed.
Keywords: Deli River, Flood, Restoration, Watershed