since the Manchester Road was moved further to the north. The next bridge downstream carries the B6088 road over the river. Below that the course used to meander across its flood plain, but had then been straightened as it ran past Stocksbridge gas works and the iron and steel works, where it fed a small reservoir. By 1931, the steel works had extended much further up the valley, taking over the gas works site, and the river had been diverted into a new channel close to the B6088 road. In parts, it had been culverted, and as the steelworks has expanded, more of it has been diverted into culverts. The culverts are long and large with some short open-air sections, and are known as 36DD by the urban exploring community, probably because both Samuel Fox, the originator of the steel works, and the model Samantha Fox were known as Sam Fox. There is also a small section of culvert below the Fox Valley shopping centre. After emerging into the open again, it is crossed by the Stocksbridge Railway, which runs from Deepcar railway station into the steelworks. It was originally a subsidiary of Samuel Fox and Company but since 1992 it has been owned by the steelworks. It opened on 14 April 1877, and passenger services, which were mainly used by workers at the steelworks and pupils from Penistone Grammar School, ran until 1931. The final bridge carries the A6102 into Deepcar, after which the river flows into the left bank of the River Don. Environment The Environment Agency measure the water quality of the river systems in England. Each is given an overall ecological status, which may be one of five levels: high, good, moderate, poor and bad. 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 good or fail. The water quality of the Little Don River system, which includes the Hagg Brook, was as follows in 2019. The river system has not been classed as good quality because of sewage discharges and physical modification of the channel, which restricts the movement of fish. Like many rivers in the UK, the chemical status changed from good to fail in 2019, due to the presence