Changes

*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.  

*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.  

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| rowspan="3"|'''[[Swales: Construction|Filter Bed]]'''

|rowspan="3"|'''[[Vegetated filter strips#Design|Filter Bed]]'''

|Topsoil is overly compacted.

|Topsoil is overly compacted.

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*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).

*Core aerate; or remove [[stone]], [[mulch]] and [[vegetation]] cover and till topsoil to a depth of 20 cm; or remove and replace with uncompacted topsoil that meets design specifications. Replace stone, mulch and vegetation cover (reuse/transplant where possible).

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|Surface ponding remains for > 48 hours or surface infiltration rate is < 15 mm/h.

|[[Topsoil]] organic matter or [[phosphorus]] content too low and [[vegetation]] not thriving.  

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*Remove sediment as described above. Core aerate (for grass swales); or remove [[stone]], sediment and [[vegetation|plant]] cover and till 5 cm of yard waste compost into the exposed planting [[Soil groups|soil]] to a depth of 20 cm; or remove and replace the uppermost 15 cm of material with planting soil that meets design specifications. Test [[Infiltration: Testing|surface infiltration rate]] to confirm it has been restored to > 15 mm/h. Replace stone and plants (re-use/transplant where possible).

*Top dress with [[compost]]

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|Damage to filter bed or slide slope is present (e.g., [[erosion]] rills, animal burrows, sink holes, ruts)

|[[Topsoil]] [[pH]] is out of specification range (6.0 to 7.8) and [[vegetation]] not thriving.

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*Regrade damaged portion by raking and replant or restore [[stone]] cover. Animal burrows, sink holes and compacted areas should be tilled to 20 cm depth prior to re-grading. If problems persist, consider adding [[Level spreaders|flow spreading device]] to prevent [[erosion]] or barriers to discourage foot or vehicular traffic.

*If soil [[pH]] is lower than 6.0, amend with ground [[Phosphorus testing in media|limestone]] to raise the pH back to neutrality. If soil pH is higher than 7.8, amend with [[compost]] or [[Test pit|sulphur]] to lower the pH back to neutrality.  

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|'''[[Vegetation]]'''

|Topsoil [[soluble salts]] content exceeds 2.0 mS/cm .

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Plants not thriving and planting soil is low in organic matter (<5%) or available [[Nutrients|phosphorus]] (<12 mg/kg)

*Remove any [[Clogging|accumulated sediment]] and core aerate. If problem persists, remove [[vegetation]], till the [[topsoil]] to a depth of 20 cm to reduce compaction, or remove and replace the uppermost 15 cm of material with topsoil that meets design specifications. Replace [[vegetation]] cover (transplant where possible).

|Damage to filter bed is present (e.g., erosion rills, animal burrows, local sinking, ruts)

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*Remove [[stone]] and [[vegetation|plant]] cover and uppermost 5 cm of planting soil, spread 5 cm of yard waste compost, incorporate into [[Soil groups|soil]] to 20 cm depth by tilling. Replace stone and plants (re-use/transplant where possible).

*Re-grade damaged portion and restore [[vegetation]] cover. Animal burrows, local sinking and compacted areas should be tilled to 20 cm depth prior to re-grading and planting.  

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