Corporate Responsibility Report 2009

Part of our long-term strategy for an improved sewage service is to ensure that our treatment activities are undertaken in a way that meets our environmental responsibilities for all the impacts they have on the environment and communities that we serve. 

The majority of our older wastewater treatment works did not require odour control measures due to their location in rural and remote areas. However, towns and cities have grown, and many of our works now have large conurbations surrounding their sites as their immediate neighbours.  During the past 10 years, this has placed the issue of odour and its management much higher up in our agenda.

Since the late 1990s we’ve undertaken major investment in odour treatment.  This has been driven by the needs of our customers – the construction of the fully enclosed wastewater treatment facility at Fleetwood and major odour treatment installations at Liverpool and Davyhulme wastewater treatment works are evidence of that.

A voluntary code of practice on Odour Nuisance from Sewage Treatment Works has been produced by DEFRA.  We are supportive and fully committed to its content. Accordingly, our investment programme will see investment of £33million in odour reduction measures at 13 wastewater treatment works during this asset management programme period of 2005 to 2010.

At our Wirral waste water treatment works in Bromborough, Birkenhead and Meols £15.5million has been spent to ensure better odour management is in place.  This programme focused on:

• Treating emissions from wastewater treatment processes through improved cleaning technologies - both multi and single stage chemical scrubbers and carbon filters are now in use at the works  to reduce odours
• Building higher dispersion stacks to ensure that emissions are released higher into the atmosphere
• Reducing the risk of odours escaping from sludge treatment processes - efficient covers and seals have been put onto the sludge thickening plants
• Reducing odours escaping from tankers - odour controlled tanker loading and unloading buildings have been erected at the works
• Chemical storage vessels have been built to store chemicals in a safe and secure manner
• Air extraction and inter-stage booster fans have been installed to improve ventilation