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.