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Well over half the sediment lost from many watersheds originates as eroded soil from their uplands and bottomlands. Such erosion occurs over such a large area that it often goes unnoticed in comparison to the more spectacular losses from stream channels and gullies, yet it may be an even greater sediment source. Upland erosion is sometimes noticeable when rilling occurs at serious rates, but the 'unseen' interrill erosion, caused primarily by raindrop impact on land between rills and gullies, may also produce great quantities of sediment. This research was conducted to study interrill erosion rates for the major soils and land uses in Goodwin Creek Watershed by applying hundreds of simulated rainstorms on many different soils and cropping conditions. The transport of sediment was studied for various conditions that are typical of intensively cropped land to evaluate how much sediment would be carried from the sources to the major stream systems. The capacity of runoff to transport sediment was affected most by the steepness of the runoff flow channel. Steepnesses exceeding 1% could transport large quantities of sediment. Transport capacity also increased rapidly as flow rate increased and as sediment size decreased. This research confirms that Goodwin Creek Watershed soils are very erodible and that the resulting sediment is readily transported.