Thames Water has been issued with a fine for polluting Chase Brook in Newbury.
Reading Crown Court has ordered it to pay to costs of nearly £7,000 after the untreated sewage polluted the brook. The wildlife was severely impacted after the pollution flowed into the water in September 2012, and the Environment Agency brought the case.
Thames Water pleaded guilty and said it has made changes at the site since the incident.
Matthew Rice, Environment Agency Environment Officer said: “Water quality testing revealed that there were high levels of both ammonia and e-coli in the pond and Brook. This combined with low oxygen levels meant that recovery from the incident was a long process.
“Ammonia is toxic to aquatic organisms and low dissolved oxygen levels starve creatures of oxygen which is of course essential for life”.