As part of the EAs investigation of technologies to achieve total-N reduction is sewage treatment Severn Trent Water are undertaking a number of trials to assess the performance of a number of plants/technologies. These have been delivered or will be early in AMP 8 to allow sufficient performance data to be gathered prior to the site receiving Total-N permits. The sites in question are as follows: • Barston STW – A Nereda plant • Blymhill STW – A alternating Oxibox EBPR plant • Packington STW – An oxidation ditch (extended aeration) plant The above sites cover a range of population equivalent sizes and influent types. Case studies of the treatment approaches taken at each site will be presented along with some of the challenges faced in delivering total-N removal projects.