There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish, and chemical status, which compares the concentrations of various chemicals against known safe concentrations. Chemical status is rated as good or fail. The water quality of the Ryton was as follows in 2016. The quality of the Anston Brook has improved, as the ecological and overall status were rated poor in 2009. The river Ryton supports various types of fish. In 2006, very few lived in the upper reaches, including the Anston Brook, because the water was only of moderate quality. A number of small streams contribute to the improvement of water quality, so that wild brown trout thrive as far as Worksop. Some trout and various types of cyprinids inhabit the water below Worksop, although abstraction of water results in spawning grounds and the habitats where the young fry live drying out during most summers, which has resulted in a decline in their numbers. Nevertheless, the lower reaches are still used for organised angling, and are the only part of the River Idle system where this activity takes place.