Changes

The mean performance value recorded at the outlet for Bioretention practices' ability to remove Total [[Phosphorus]] (TP) was calculated based on 355 separate recordings between 2005-2007, 2011-2019 and 2021 amongst the seven sites previously mentioned.

The mean performance value recorded at the outlet for Bioretention practices' ability to remove Total [[Phosphorus]] (TP) was calculated based on 355 separate recordings between 2005-2007, 2011-2019 and 2021 amongst the seven sites previously mentioned.

As can be seen in the corresponding boxplot the mean performance removal efficiency of the bioretention practices monitored are not meeting the acceptable upper extent range of nutrients as of 0.03 mg/L (30 µg/L) (Environment Canada, 2004<ref name="example1">Environment Canada. (2004). Canadian guidance framework for the management of phosphorus in freshwater systems. Ecosystem Health: Science‐based solutions report no. 1–8. Cat. No. En1–34/8–2004E. </ref>; <ref>Ontario Ministry of Environment and Energy (OMOEE). 1994. Policies, Guidelines and Provincial Water Quality Objectives of the Ministry of Environment and Energy. Queen’s Printer for Ontario. Toronto, ON.</ref>).

As can be seen in the corresponding boxplot the mean performance removal efficiency of the bioretention practices monitored are not meeting the acceptable upper extent range of nutrients as of 0.03 mg/L (30 µg/L) (Environment Canada, 2004<ref name="example1">Environment Canada. (2004). Canadian guidance framework for the management of phosphorus in freshwater systems. Ecosystem Health: Science‐based solutions report no. 1–8. Cat. No. En1–34/8–2004E. </ref>; OMOEE, 1994<ref>Ontario Ministry of Environment and Energy (OMOEE), 1994. Policies, Guidelines and Provincial Water Quality Objectives of the Ministry of Environment and Energy. Queen’s Printer for Ontario. Toronto, ON.</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 and provincial governments' guideline requirement for stormwater quality.

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 and provincial governments' guideline requirement for stormwater quality.