biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish. Chemical status, which compares the concentrations of various chemicals against known safe concentrations, is rated good or fail. The water quality of the Foudry Brook system was as follows in 2019. Water quality on Silchester Brook has improved from poor in 2015 to moderate in 2016. Most of the reasons for it not achieving good quality are connected with sewage discharge. West End Brook dropped from moderate to bad in 2015, and the reasons for it not being good are mainly to do with physical modification of the channel, which prevents fish freely moving around the system, and the presence of the invasive species, the North American signal crayfish. Burghfield Brook is affected by discharges from industry, and the main factors affecting the Foudry Brook are physical modification of the channel and sewage discharge. The brook is prone to flooding along its length, which has caused the most problems on the outskirts of Whitley, where its water voles hinder raising banks and expansion of water-meadows. Pollution In an action brought by the Environment Agency in 2002, Total Fina Elf UK Ltd was fined £54,000 for causing petrol to enter groundwater and a tributary of the Foudry Brook, from its service station in Tadley. Between January 1999 and March 2001 from 2,000 up to 10,000 litres seeped into the ground from leaks in an underground petrol tank, and from filler and suction lines. In July 2010 a serious leak from sewage works into the Brook near Silchester killed hundreds of fish and many other organisms on a three-mile stretch. Bibliography References External links Rivers of Berkshire 1Foudry