Greenough River
The Greenough River lies east of Geraldton, just over 400 km north of Perth. The Greenough River has the largest catchment land area in the Greenough basin at about 12,500 km2. The Greenough River headwaters are on the Yilgarn Plateau about 60 km north of Yalgoo. From its headwaters, the Greenough River flows south west for about 340 km, through the Waterloo Range, and discharges to the Indian Ocean at Cape Burney, about 10 km south of Geraldton.
Average annual rainfall varies between about 450 mm on the coast, falling to about 260 mm in the east of the catchment on the Yilgarn plateau. The upper (eastern) half of the catchment is uncleared, and land use is classed as minimal use; while in the lower (western) half of the catchment, unirrigated cropping is the dominant land use, with grazing more common moving closer to the coast. A section of the lower Greenough River, through Ellendale and Minnenooka, is a gaining section of river and here groundwater often supplements surface flow or helps maintain permanent pools though this section of the river.