Changes

Non-proprietary [[bioretention]] systems are sized as filters much more conservatively based on design storms, surface ponding depth and [[Flow through media|minimum media infiltration rate]].  The ratio of drainage area imperviousness to the surface area of bioretention facilities (referred to as the impervious-to-pervious ratio) is often many times lower than that for filtration MTDs.  This ensures longer intervals for sediment maintenance and significant reductions in stormwater volumes through infiltration.

Non-proprietary [[bioretention]] systems are sized as filters much more conservatively based on design storms, surface ponding depth and [[Flow through media|minimum media infiltration rate]].  The ratio of drainage area imperviousness to the surface area of bioretention facilities (referred to as the impervious-to-pervious ratio) is often many times lower than that for filtration MTDs.  This ensures longer intervals for sediment maintenance and significant reductions in stormwater volumes through infiltration.

[[File:Screenshot 2025-07-14 135310.png|300px|thumb|right|Filter media replacement in bioretention system (Filterra®)<ref>https://www.conteches.com/media/wlrdhu4w/filterra-vault-om.pdf</ref>]]

[[File:Screenshot 2025-07-14 135310.png|300px|thumb|right|Filter media replacement in bioretention system (Filterra®)<ref>Contech Engineered Solutions. 2024. Filterra Vault Owner’s Manual. https://www.conteches.com/media/wlrdhu4w/filterra-vault-om.pdf</ref>]]

==Maintenance considerations==

==Maintenance considerations==