Sewage discharges: calculator for domestic properties

Daily discharge volume calculator for small sewage discharges from septic tanks and package treatment plants


Daily discharge calculator for domestic properties

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Use this calculator tool to work out the daily discharge volume from a septic tank or package treatment plant which is connected to one or more houses or flats.

This will help you decide whether you need to comply with the general binding rules or if you need to apply for an environmental permit.

Published 4 June 2015
Last updated 31 July 2019 + show all updates
  1. Added the calculator in an open document spreadsheet format.

  2. First published.