Textile dyeing within the Severn Trent Region of England produces highly coloured wastewater. This dyewaste is usually discharged untreated to foul sewer. Conventional treatment at the receiving sewage treatment works removes little colour resulting in coloration of effluents and rivers in certain areas. The regulatory body (N. R. A.) has set strict colour standards on 5 sewage works in the region. These standards are based on a River Quality Objective (R. Q. O.). Methods of removing colour are reviewed. The full scale ozone colour removing colour are reviewed. The full scale ozone colour removal plant at Leek is described and early operating data is given. Good colour removal has been obtained, but compliance with the consent has been 89.7％ and not the 100％ required. Data is presented to indicate that the R. Q. O. does not adequately take natural colour into account. Target absorbances at 400 and 450nm are thus too low to be practicable for the derived sewage effluent consents.