Desludge 20M lagoon using Bactech 362 bacteria in lieu of mechanical desludging lagoon


Project Commencement Date: 20/09/2017

Project Completion Date: 12/12/2017

This client is a testament to the value of Bactech's expert advice and the range of products Bactech has to offer to the sewage and waste water treatement industry in Australia. This client has consistently and reliably benefitted from significant savings in numerous areas including:

  • reduced sludge dewatering, hanling and disposal costs
  • Increased treatment capacity and more robust process
  • Improved effuent quality and sludge settlement

Day 1

Evaluation of CAL2

Westend of CAL (evidence of sluge build up exceeding top of water level)


  • pH - 5.15
  • COD - 12750
  • Estimated level of sludge (noticeable at 14M water volume)


  • pH - 4.99
  • COD - 10900 (reduced)
  • Estimated level of sludge (no evidence of sludge at 13.6M water volume)
  • Bad odour smell (a lot of complaints), a lot of biological actibity (air bubles), clumps breaking and floating to surface
  • Water clarity chanign from purply wine colour to clear/slightly brown


  • pH - 4.87
  • COD - 10150 (slight reduction compared to previous)
  • Estimated level of sludge (no evidence of sludge at 13M water volume - estimated 40-50% reduction in sludge)
  • Sludge at bottom easier to push through (becoming soft), when pushing through clumps of solid mass floating to the top
  • Odour reduced but still evident
  • Water clarity improved


  • pH - 4.89
  • COD - 7370 (reduction of 45%)
  • Litttle evidence of odour
  • Biological activity still evident
  • Clumps still breaking off
  • Hard to guage sludge level, as level in lagoon is now at 19M, however softer to push pole through, pole seeems to go through bottom of CAL floor

Project Summary

  • Odour went from being really bad to negligible
  • COD has reduced by 45%
  • Reduction of sludge volume grom 3.6M to around 0.9m (75% reduction)
  • Sludge softer to break through at bottom of CAL


  • ClientDesludging of CAL2
  • Date10 Sep 2018
  • CategoriesIndustry