Investigation of Air Resuspension Technique in Combination with Geotextile Bag Filtration for Remediation of High Phosphorus Content Lake Sediment

Phosphorus, a macronutrient, has been challenging for nations to cope with as the leading cause of eutrophication in inland waters (i.e., lakes). This nutrient has been overloading lakes due to diverse external and/or internal nutrient sources. Commonly most of this discharged phosphorus is incorporated into sediments, which in some circumstances are released back into the water column consequently triggering recurring eutrophication scenarios. From a possible water remediation perspective, practices commonly used, apart from dredging, do not directly address lake sediment. In this investigation, a resuspension technique followed by geotextile filtration was employed as a procedure for remediating/attenuating higher phosphorus concentrations in sediments of a mesotrophic lake, Lake Canard located in Sainte-Anne-des-Lacs, Quebec. The experimental study was simulated using a confined water column. Thus, this study aims to investigate the feasibility and efficiency of the resuspension method followed by geotextile bag filtration to reduce particles in the water suspension created. Water samples on this experiment were measured before and after resuspension and filtration for the following parameters: soluble reactive phosphorous (SRP), particle size, and total suspended solids (TSS). Sediment on the other hand was evaluated for total phosphorus before and after. Results on the water suspension filtration have indicated a reduction of around 80% in particle size with SRP reduction near 65% after resuspension/filtration and TSS attenuation of 30%. Also, for TP attenuation on sediment, a reduction of 22% was achieved after resuspension/filtration, thus implying the feasibility of the procedure.