Mogden formula tool
The Mogden Formula calculates the charges water companies apply to industry for the conveyance and treatment of effluents discharged to sewer.
The Mogden Formula tool is a Microsoft® Excel-based tool that allows you to apply your data in an automated way. The tool uses water companies' standard tariffs, but if you are a large water user there is an 'other tariffs' option which allows you to enter industrial tariffs.
The tool also allows the user to investigate the impact of modifying specific aspects of the effluent on the cost to discharge. For example the flow, COD and SS can all be modified independently to investigate whether a preliminary treatment system may be a cost-effective option to consider.
The Mogden Formula Tool has been updated to include the new trade effluent charges for 2008-2009 that are applied by the water companies in England and Wales, Northern Ireland and Scotland. The tool also includes data from the previous year so that comparisons can be made between water companies' changing tariffs.
Download now: EOC Mogden Formula Tool UK 2008-9.
We recommend that you save this tool to your computer rather than open it online as it can cause errors when running embedded into Internet Explorer. For Excel 2000 and higher versions you will need to make sure the Tools Macro Security setting in Excel is set to 'low' before you open the spreadsheet.
If you are not getting the option to Open or Save the document when clicking the link, please set your internet explorer security options to 'enable download' or ask your IT for further assistance
The Mogden Formula
The formula was agreed between the water industry and the Confederation of British Industry and attempts to link charges to trade effluent customers to the costs that they impose, ie customers pay according to the volume and strength of the effluent they discharge.
The formula comprises a number of coefficients relating to the volume, chemical oxygen demand (COD) and suspended solids (SS) of the discharge. The formulae applied by different companies vary somewhat in their structure and format. For example, some water companies that operate wastewater treatment works with marine discharges have a factor which can be applied for marine outfalls and this option is included as an integral part of the tool.
Please see this publication about Calculating trade effluent costs: the Mogden Formula for detailed calculations.
