Sludge quantification and influence of aeration on sludge blanket at Town of Fernie, BC Wastewater Lagoon ​

---

Client's challenge: Identify whether dredging in cells 1 and 2 was necessary and determine sludge volume and composition for dredge project budgeting.
Hydrasurvey's solution: Hydrasurvey conducted sludge surveys in two aerated cells at the town of Fernie, BC's wastewater lagoon. 

• The sludge surveys determined the in-situ sludge volume, dry tonnes of sludge, sludge composition and showed the influence of the aeration system on the sludge, which allowed contractors to provide accurate pricing to dredge the cells. 
• The sludge surveys also showed a possible restriction issue with the aeration in cell 2. A localized build-up of sludge in cell 2 appeared to be burying aeration diffusers and causing more of a sludge build-up near the cell inlet. This allowed the town to specifically assess the aeration in that particular area of the pond.