CS supported Severn Trent in developing deterioration and reliability models for the 2009 periodic review of prices.  We managed the development and delivery of deterioration and reliability models for the non-infrastructure assets over a two-year period.  This included managing the internal water company project team as well as the engaged consultancies.

A suite of deterioration models were developed using Severn Trent failure data.  These deterioration models were used to model overall reliability at sewage treatment works, water treatment works, sewage pumping stations, water pumping stations, and sludge treatment centres.  A set of reliability models were produced – with the failure rate and impact of service without and with investment over 25 years modelled.

In addition we implemented Investment Manager (IM) at Severn Trent.  Investment Manager was used to hold the non-infrastructure modelled data, alongside infrastructure modelled data and all non-modelled investment risks.  Investment Manager was used to produce the optimised draft and final business plans for the 2009 periodic review of prices, and is currently being developed into a business-as-usual process.