Changes

[[File:Treatment train air force.JPG|thumb|800px|An example of a stormwater treatment train approach at Tyndall Air Force Base in Florida, in a coastal environment. This example includes source controls of [[bioretention]] parking islands, [[permeable pavement]], and conveyance controls of[[swales]], a natural infiltration basin in a forested woodlot, and end-of-pipe controls of [[dry ponds]], [[constructed wetlands]] and coastal dunes. All of these features help to reduce traditional SWM features' maintenance, treatment and rehabilitation coasts, while also reducing pollutants into the receiving waterbody. (U.S Air Force, 2020)<ref>U.S. Air Force. n.d. LANDSCAPE MASTER PLAN - C. Site Development Criteria.  CO4. Stormwater - C04.3.2 Stormwater at Individual Building Sites. Accessed: https://www.tyndallifs.com/images/LMP_pdf/TAFB_Final_LandscapeMasterPlan_2020-09-24_SectionC04.pdf</ref>]]

[[File:Treatment train air force.JPG|thumb|800px|An example of a stormwater treatment train approach at Tyndall Air Force Base in Florida, in a coastal environment. This example includes source controls of [[bioretention]] parking islands, [[permeable pavement]], and conveyance controls of[[swales]], a natural infiltration basin in a forested woodlot, and end-of-pipe controls of [[dry ponds]], [[constructed wetlands]] and coastal dunes. All of these features help to reduce traditional SWM features' maintenance, treatment and rehabilitation coasts, while also reducing pollutants into the receiving waterbody. (U.S Air Force, 2020)<ref>U.S. Air Force. n.d. LANDSCAPE MASTER PLAN - C. Site Development Criteria.  CO4. Stormwater - C04.3.2 Stormwater at Individual Building Sites. Accessed: https://www.tyndallifs.com/images/LMP_pdf/TAFB_Final_LandscapeMasterPlan_2020-09-24_SectionC04.pdf</ref>]]

'''Example''': Runoff into larger treatment practices such as [[bioretention]] or [[stormwater tree trenches]] may be pretreated by [[Inlet sumps: Gallery|concrete sumps]] at [[curb cut]] inlets, [[forebays]] or catch basin inserts, which are designed to capture coarse sediment, debris and trash.  Centralizing sediment and trash captured at the inlet or entrance to the facility reduces maintenance by preventing [[filter media]] [[clogging]] and limiting the area over which sediment and trash needs to be removed.  In some cases, pre-treatment device clean-outs may be incorporated into existing municipal catch basin cleaning programs.   

'''Example''': Runoff into larger treatment practices such as [[bioretention]] or [[Stormwater Tree Trenches|stormwater tree trenches]] may be pretreated by [[Inlet sumps: Gallery|concrete sumps]] at [[curb cut]] inlets, [[forebays]] or catch basin inserts, which are designed to capture coarse sediment, debris and trash.  Centralizing sediment and trash captured at the inlet or entrance to the facility reduces maintenance by preventing [[filter media]] [[clogging]] and limiting the area over which sediment and trash needs to be removed.  In some cases, pre-treatment device clean-outs may be incorporated into existing municipal catch basin cleaning programs.   

'''Performance calculation''': If the downstream facility provides filtration, such as [[bioretention]] or [[Infiltration trenches|stone filled trenches]], the overall water quality performance of this facility would not increase with [[pretreatment]] because the coarse sediment and debris captured by the pretreatment device would be removed by the downstream facility even in the absence of pretreatment.  The purpose of adding pre-treatment is to prevent clogging or filling and thereby reduce the cost and effort of long term [[Inspections and maintenance|maintenance]] and delay requirements for major facility [[Maintenance, Rehabilitation and Repair|rehabilitation or replacement]].

'''Performance calculation''': If the downstream facility provides filtration, such as [[bioretention]] or [[Infiltration trenches|stone filled trenches]], the overall water quality performance of this facility would not increase with [[pretreatment]] because the coarse sediment and debris captured by the pretreatment device would be removed by the downstream facility even in the absence of pretreatment.  The purpose of adding pre-treatment is to prevent clogging or filling and thereby reduce the cost and effort of long term [[Inspections and maintenance|maintenance]] and delay requirements for major facility [[Maintenance, Rehabilitation and Repair|rehabilitation or replacement]].

[[File:Sump inelt to chamber system.JPG|thumb|500px|Example of a [[Pretreatment#Concentrated underground flow|overland flow sump inlet]] allowing sediment to settle out of influent stormwater before entering a large infiltration chamber housed under a parking lot/ The outlet control device can then drain into a [[dry pond]] furthu downstream or offsite (Source: Philadelphia Water Department. 2020)<ref>Philadelphia Water Department. 2020. Stormwater Management Guidance Manual: Version 3.2. Accessed from: https://www.pwdplanreview.org/upload/manual_pdfs/PWD-SMGM-v3.2-20201001.pdf</ref>]]

[[File:Sump inelt to chamber system.JPG|thumb|500px|Example of a [[Pretreatment#Concentrated underground flow|overland flow sump inlet]] allowing sediment to settle out of influent stormwater before entering a large infiltration chamber housed under a parking lot/ The outlet control device can then drain into a [[dry pond]] furthu downstream or offsite (Source: Philadelphia Water Department. 2020)<ref>Philadelphia Water Department. 2020. Stormwater Management Guidance Manual: Version 3.2. Accessed from: https://www.pwdplanreview.org/upload/manual_pdfs/PWD-SMGM-v3.2-20201001.pdf</ref>]]

===2. Treatment trains designed to address one or more design criteria===  

===2. Treatment trains designed to address one or more design criteria===