Gully erosion is a major contributor to suspended sediment and associated nutrient pollution (e.g. gullies generate approximately 40 % of the sediment pollution impacting the Great Barrier Reef). This study used a new method of monitoring to demonstrate how large-scale earthworks used to remediated large gullies (i.e. eroding landforms > 1 ha) can drastically improve the water quality of connected waterways and, thus, protect vulnerable ecosystems in downstream-receiving waters.