Water Quality - Biological Oxygen Demand (BOD) Monitoring

Chelsea Technologies Group (CTG) has addressed the challenges faced by  water process engineers to assess real-time levels of BOD in water systems with the introduction of the following new products. Both systems provide instant measurements of BOD avoiding lengthy, potentially costly, delays in obtaining laboratory results.






The BOD-Station and BOD-Wader systems enable in-line or in situ real-time reporting of Biological Oxygen Demand within both water processing plants and natural water systems. The monitor detects fluorescent proteins that are inherent within sewage and slurry. 


The principle behind the measurement is the excitation of Tryptophan-like fluorescence within UV wavelength band, which is highly sensitive and has been shown to correlate with Biological Oxygen Demand.  These systems can inform on how the bacterial removal systems within a Waste Water Treatment Works are performing.


Applications for the BOD-Station & BOD-Wader include:

  • BOD loading to Waste Water Treatment Works (WWTW)
  • Monitoring efficacy of separate processing tanks within WWTWs
  • Assessment of WWTW outflow compliance
  • Monitoring industrial effluent discharge into surface waters
  • River pollution surveillance and investigative monitoring
  • Point source pollution surveys
  • Farm run-off detection and tracking
  • Assessment of bathing & shellfish waters
  • Groundwater quality monitoring
  • Combined Sewage Overflow (CSO) event detection
  • Faecal Indicator (FI) monitoring

What is BOD?:

Biochemical Oxygen Demand (BOD) measures the amount of oxygen consumed by microorganisms when decomposing organic matter. BOD also measures the chemical oxidation of inorganic matter (ie the extraction of oxygen from water via chemical reaction).

Breaking News:

Academic Collaboration with the University of West of England
Dr Darren Reynolds, Associate Professor in Bio-Sensing Research at the University of the West of England is a recognised authority in the use of  fluorescence measurements for water quality monitoring, having published widely in this area for over a decade.  "For the past two years we have been collaborating very successfully with Dr Reynold’s group to both evaluate and optimise our UviLux fluorometers for BOD monitoring and other applications in the water industry," reports Chelsea's Technical Director, Dr John Attridge.

Download presentations & video shown at the "New Sensors for Effluent Monitoring Workshop"

During the New Sensors for Effluent Monitoring Workshop Dr Darren Reynolds, Associate Professor in Bio-Sensing Research at the University of the West of England presented an overview of fluorescence measurements and their applications to water quality. Chelsea's Dr John Attridge, Technical Director presented information, field data and demonstrated the new UviLux BOD Indicator.