Bell Island Treatment Ponds Sludge Survey Report Nov 2017

Conhur provides sludge surveys for both sludge lagoons and oxidation ponds. We utilize the latest technology to provide as accurate a result as possible.  Our sludge surveys provide estimates of: 


  • The volume of sludge contained within the ponds
  • The average solids content of the sludge contained in the ponds
  • The total tonnes dry solids (tDS) contained within the ponds


Conhur was contracted by Nelmac, on behalf of Nelson City Council, to survey the sludge contained in the three facultative ponds and two maturation ponds at the Bell Island WWTP. The survey was undertaken over a period of two days from 29 to 30 October 2017 in fine, medium winds and warm weather conditions. This was a follow up to previous surveys completed on the same ponds by Conhur in November 2015, June 2014 and November 2012.

Download the full report (5.8MB PDF)