| '''Example:''' A bioretention and infiltration chamber in series. Adding the second facility increases the overall area available for infiltration, which in turn reduces the overall load of pollutants to the receiver. This type of treatment may be advantageous where surface space is limited, but water balance requirements can not be met with available space allocated to the surface bioretention cell alone. | | '''Example:''' A bioretention and infiltration chamber in series. Adding the second facility increases the overall area available for infiltration, which in turn reduces the overall load of pollutants to the receiver. This type of treatment may be advantageous where surface space is limited, but water balance requirements can not be met with available space allocated to the surface bioretention cell alone. |
− | '''Performance calculation''': In the example above, the [[bioretention]] facility would provide water quality load reductions through filtration (water quality concentration reductions) and infiltration (volume reductions). Since the second facility would receive effluent from the [[underdrain]] of the bioretention, no further reduction in TSS concentrations would be expected (ie. the TSS concentration would already be at the ‘irreducible’ level) (Schueler, 2000)<ref>Schueler, T. 2000. Irreducible Pollutant Concentration Discharged from Stormwater Practices. Technical Note #75, In Watershed Protection Techniques. 2(2), 369-372, Centre for Watershed Protection. Accessed: https://owl.cwp.org/mdocs-posts/elc_pwp65/</ref>. The TSS water quality load would be reduced in the second facility only by further reductions in volumes through infiltration. If the parameter of interest was total [[phosphorus]] (TP) rather than TSS, there is the potential that the second facility may further reduce TP through filtration/adsorption, especially if the second facility contained [[Sorbtive media|reactive media]] designed to remove phosphorus. | + | '''Performance calculation''': In the example above, the [[bioretention]] facility would provide water quality load reductions through filtration (water quality concentration reductions) and infiltration (volume reductions). Since the second facility would receive effluent from the [[underdrain]] of the bioretention, no further reduction in TSS concentrations would be expected (ie. the TSS concentration would already be at the ‘irreducible’ level) (Schueler, 2000)<ref>Schueler, T. 2000. Irreducible Pollutant Concentration Discharged from Stormwater Practices. Technical Note #75, In Watershed Protection Techniques. 2(2), 369-372, Centre for Watershed Protection. Accessed: https://owl.cwp.org/mdocs-posts/elc_pwp65/</ref>. The TSS water quality load would be reduced in the second facility only by further reductions in volumes through infiltration. If the parameter of interest was total [[phosphorus]] (TP) rather than TSS, there is the potential that the second facility may further reduce TP through filtration/adsorption, especially if the second facility contained [[Sorbtive media|reactive media]] designed to remove phosphorus.<br> |