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==Rehabilitation & Repair==
==Rehabilitation & Repair==


Table below provides guidance on rehabilitation and repair work specific to enhanced grass swales organized according to BMP component.
Table below provides guidance on rehabilitation and repair work specific to vegetated/grass filter strips and soil amendments organized according to BMP component.
   
   
[[File:Outlet covered swale.PNG|330px|thumb|link=https://sustainabletechnologies.ca/app/uploads/2018/02/Enhanced-Swales-Fact-Sheet.pdf|An example of an outlet in an enhanced swale requiring maintenance to remove built up debris and sediment. <ref>TRCA. 2018. Inspection and Maintenance of Stormwater Best Management Practices - Enhanced Swales. Fact Sheet. https://sustainabletechnologies.ca/app/uploads/2018/02/Enhanced-Swales-Fact-Sheet.pdf</ref>]]
[[File:Levelspread.jpg|thumb|430px|This clever design incorporates a level spreading device after a [[curb cut]] has narrowed the flow path. This kind of treatment train approach would provide an opportunity to provide [[pretreatment]] at the point of concentration. This repair helps to limit the potential of erosion occurring within the feature. Photo credit: [https://www.pca.state.mn.us/featured/when-it-rains-it-flows (MPCA, 204)]<ref>Minnesota Pollution Control Agency. 2014. When it rains, it flows. 6 May 2014. Accessed 156 July 2022. https://www.pca.state.mn.us/featured/when-it-rains-it-flows</ref>]]  
 
 
{|{| class="wikitable" style="width:900px;"
{|{| class="wikitable" style="width:900px;"
|+'''Enhanced Swales: Key Components, Typical Issues and Rehabilitation Requirements'''
|+'''Vegetated Filter Strips and Soil Amendments Key Components, Typical Issues and Rehabilitation Requirements'''
|-
|-
!Component
!Component
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|'''[[Inlets]]'''
|'''[[Inlets]]'''
|
|
Inlets are producing concentrated flow and causing filter bed erosion
Inlet or flow spreading device is producing concentrated flow and causing filter bed erosion.
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|
*Add [[Level spreaders|flow spreading device]] or re-grade existing device back to level. Rake to regrade damaged portion of the filter bed and replant. If problem persists, replace some [[vegetation|plant]] cover with [[stone]].
*Add [[Level spreaders|flow spreading device]] or re-grade existing device back to level to promote sheet flow to the filter bed. Regrade damaged portion of the filter bed and replant. If problem persists, consider adding [[turf grasses|turf]] reinforcement devices or replace filter bed [[vegetation]] cover with stone at inlets.  
|-
|-
| rowspan="3"|'''[[Swales: Construction|Filter Bed]]'''
| rowspan="3"|'''[[Swales: Construction|Filter Bed]]'''
|Local or average sediment accumulation ≥ 5 cm in depth.
|Topsoil is overly compacted.
|
|
*At [[inlets]] remove [[stone]] and use vacuum equipment or rake and shovel to remove sediment. For large areas or BMPs, use of a small excavator may be preferable. Restore grades with planting soil that meets design specifications. Test surface infiltration rate to confirm it is > 15 mm/h. Replace [[stone]] and [[vegetation]] coverage (re-use/transplant where possible). If problem persists, add [[pretreatment]] device(s) or investigate the source(s).
*At [[inlets]] remove [[stone]] and use vacuum equipment or rake and shovel to remove sediment. For large areas or BMPs, use of a small excavator may be preferable. Restore grades with planting soil that meets design specifications. Test surface infiltration rate to confirm it is > 15 mm/h. Replace [[stone]] and [[vegetation]] coverage (re-use/transplant where possible). If problem persists, add [[pretreatment]] device(s) or investigate the source(s).

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