The development of an odour risk assessment method for Anglian Water
Jones, E.1, Dean, J.2 and Bull, M.3, 1Waterman Group,2Anglian Water, 3Ove Arup and Partners Ltd, UK
(free)
This paper describes the development of an odour risk assessment methodology that is now being used by Anglian Water to screen planning applications made near to their works. Anglian Water wish to avoid incompatible development near to their works and therefore screen planning applications, to assess the risk that the proposed new development may be subject to odours, that may result in annoyance. To develop the risk assessment methodology a survey of site managers was undertaken to collate their experience on what factors result in odour complaints being made. This information, together with the results of odour modelling were then used to develop the risk assessment method that has been adopted by Anglian Water as part of their Asset Encroachment Policy.
Introduction
Anglian Water operates hundreds of sewage treatment works (STWs), and one of the frequent issues they are faced with is planning applications made in close proximity to their STWs.
In common with all water companies, Anglian Water wishes to avoid having incompatible land uses near to their works, as this can result in new complaints being made against their operations, particularly regarding odours. As a result, the company has a planning department that monitors and responds to planning applications made near to their STWs. The company originally had an encroachment policy with a general presumption against all development within 400m. Anglian Water recognised that this was not consistent with policy and decided to develop a site specific risk assessment methodology to determine the importance odour issues would have in specific circumstances.
The development of this methodology was undertaken as an MSc project with industrial supervision. The intention of the method was that it would be used as a first stage decision-making tool, to help determine how Anglian Water will respond to planning applications made near to their STWs. The criteria used within the risk assessment methodology were to be based on a combination of the company’s experience and a detailed assessment of the likely risk factors.
The main tasks in the study were as follows:
- To collate Anglian Water’s site manager’s experience of odour issues at their sites and to identify the processes, operations and other factors that are most likely to give rise to odour issues;
- To develop and evidence a set of criteria to use within the risk assessment methodology;
- To undertake odour modelling to determine typical odour footprints of various size ranges of STWs;
- Prepare a simple overall methodology for use in assessing planning applications for their likely risk of creating an odour issue;
- To test the methodology developed on planning applications; and,
- To create a guidance document to be used alongside the risk assessment methodology to demonstrate how the methodology was developed.
Keywords: Odour, Odour Modelling, Odour Assessment, Sewage Odours, Encroachment
