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https://sustainabletechnologies.ca/app/uploads/2015/06/SynthesisWaterQuality_Statistics_May2015.pdf
→TSS Reduction
The mean performance value recorded at the outlet for Bioretention practices' ability to remove Total Suspended Sediments (TSS) was was calculated based on 301 separate recordings between 2005-2007, 2011-2019 and 2021 amongst the six sites previously mentioned.
The mean performance value recorded at the outlet for Bioretention practices' ability to remove Total Suspended Sediments (TSS) was was calculated based on 301 separate recordings between 2005-2007, 2011-2019 and 2021 amongst the six sites previously mentioned.
As can be seen in the corresponding boxplot the mean performance removal efficiency of the bioretention practices monitored are well below the suggested guideline of 30 mg/L (Canadian Water Quality Guideline (CWQG), </ref>).
As can be seen in the corresponding boxplot the mean performance removal efficiency of the bioretention practices monitored are well below the suggested guideline of 30 mg/L (Canadian Water Quality Guideline (CWQG), or
(background (assumed at <5 mg/L)+ 25 mg/L for short term (<24 hour) exposure) (CCME, 2002<ref>Canadian Council of Ministers of the Environment (CCME). 2002. Canadian water quality guidelines for the protection of aquatic life: Total particulate matter. In: Canadian Environmental Quality Guidelines, Canadian Council of Ministers of the Environment, Winnipeg</ref>; (TRCA, 2021<ref>TRCA. 2021. Spatial Patterns (2016-2020) and Temporal Trends (1966-2020) in Stream Water Quality across TRCA’s Jurisdiction Prepared by Watershed Planning and Ecosystem Science. https://trcaca.s3.ca-central-1.amazonaws.com/app/uploads/2021/10/29113334/2016-2020-SWQ-Report-v11_FINAL_AODA-FA.pdf</ref>).
The median value of the 355 samples taken was '''0.87 mg/L''' whereas the mean was '''0.123 mg/L''', with an 86% guideline exceedance. Given the age of most of these practices, more inspection, maintenance and necessary rehabilitation will be needed to ensure they are able to meet the federal government's guideline requirement for stormwater quality.
The median value of the 301 samples taken was '''9.50 mg/L''' whereas the mean was ''' 18.63 mg/L''', with a '''15%''' guideline exceedance.
==References==
==References==