Changes

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*Check for damage or vegetation;

*Check for damage or vegetation;

*Remove any vegetation or natural debris

*Remove any vegetation or natural debris annually to biannually.

annually to biannually.

|[[File:CDA Pass p.p.JPG|300px|thumb|center|CDA has not changed in size or land cover. Sediment, trash or debris is not accumulating and point sources of contaminants are not visible.]]  

|[[File:CDA Pass p.p.JPG|300px|thumb|center|CDA has not changed in size or land cover. Sediment, trash or debris is not accumulating and point sources of contaminants are not visible.]]  

|[[File:CDA Fail p.p.JPG|280px|thumb|center|Size of the CDA has changed from design assumptions (i.e. large asphalt area drains to a small portion of the permeable pavement). Evidence of surface ponding is visible.]]  

|[[File:CDA Fail p.p.JPG|280px|thumb|center|Size of the CDA has changed from design assumptions (i.e. large asphalt area drains to a small portion of the permeable pavement). Evidence of surface ponding is visible.]]  

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|'''[[Inspection and Maintenance:Growing medium/filter bed|Growing medium/filter bed]]'''

|'''[[Green roof media|Growing medium/filter bed]]'''

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Devices or features that retain trash, debris and sediment; help to extend the [[Cost analysis resources|operating life cycle]]; examples are eavestrough screens, [[Pretreatment|catch basin]] inserts and sumps, [[oil and grit separators]], [[inlets|geotextile-lined inlets]], [[Gravel diaphragms|gravel trenches]], [[Vegetated filter strips|grass filter strips]] and [[forebays]].

Flat or gently sloping area covered by growing medium and a mixture of plants. Growing medium varies according to the green roof system or product but is generally designed to be porous and lightweight with adequate fertility and moisture retention to support plant growth while maintaining drainage of excess water within a few hours after a storm or snowmelt event. May be covered by matting/other erosion control product to prevent rain/wind scour while plantings are becoming established.

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*Remove trash, debris and sediment annually to biannually or when the device sump is half full;

*Check for standing water, animal burrows or damage from foot traffic, rain or wind scour;

*Measure sediment depth or volume during each cleaning, or annually to estimate accumulation rate and optimize frequency of maintenance.

*Replace erosion/scour protection where missing or uplifted;

*Remove trash and natural debris annually to biannually.

|[[File:Pretreat Pass p.p.JPG|280px|thumb|center|Although permeable pavers are generally considered [[pretreatment]] for other BMPs in a [[Low impact development treatment train tool|treatment train]] system, using eavestrough screens can act as pretreatment as they don't add to sediment build up and accumulation on the paver surface. (Photo Source: Guertin, 2010)<ref>Guertin, M. 2010. Simple Screen Gutter Guards Better Than Pro-Installed Systems (and way cheaper). Fine Homebuilding - The Daily Fix. Accessed July 17 2022. https://www.finehomebuilding.com/2010/08/17/simple-screen-gutter-guards-better-than-pro-installed-systems-and-way-cheaper</ref>]]  

|[[File:Pretreat Pass p.p.JPG|280px|thumb|center|Although permeable pavers are generally considered [[pretreatment]] for other BMPs in a [[Low impact development treatment train tool|treatment train]] system, using eavestrough screens can act as pretreatment as they don't add to sediment build up and accumulation on the paver surface. (Photo Source: Guertin, 2010)<ref>Guertin, M. 2010. Simple Screen Gutter Guards Better Than Pro-Installed Systems (and way cheaper). Fine Homebuilding - The Daily Fix. Accessed July 17 2022. https://www.finehomebuilding.com/2010/08/17/simple-screen-gutter-guards-better-than-pro-installed-systems-and-way-cheaper</ref>]]  

|[[File:Pretreat Fail p.p.JPG|300px|thumb|center|Build up of leads, sediment and leaf detritus in an eavestrough downspout disconnection leading to a permeable pavement surface. If not cleaned regularly this can lead to clogged pores between the pavers reducing the infiltration rate where the downspout deposits water onto the feature. (Photo Source: My Gutter Pro, 2021)<ref>My Gutter Pro. 2021. Clogged Downspout : Causes and Solutions. 10 April 2021. Accessed July 19 2022. https://mygutterpro.com/downspout-clog/</ref>]]  

|[[File:Pretreat Fail p.p.JPG|300px|thumb|center|Build up of leads, sediment and leaf detritus in an eavestrough downspout disconnection leading to a permeable pavement surface. If not cleaned regularly this can lead to clogged pores between the pavers reducing the infiltration rate where the downspout deposits water onto the feature. (Photo Source: My Gutter Pro, 2021)<ref>My Gutter Pro. 2021. Clogged Downspout : Causes and Solutions. 10 April 2021. Accessed July 19 2022. https://mygutterpro.com/downspout-clog/</ref>]]  

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

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

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Applies to grid paver systems only; a mixture of deep rooting perennial grasses or low growing ground covers, tolerant to both wet and dry conditions and salt (if receiving impermeable pavement runoff); roots uptake water and return it to the atmosphere, provide habitat for soil organisms that break down pollutants trapped in the soil and help maintain soil structure and permeability.

[[Green roofs: Planting|Plants]] should be tolerant of the harsh conditions prevalent on rooftops. Use of a wide variety of plants may improve resilience but complicates maintenance and may require staff or contractors trained in horticulture

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*Grid systems with soil and grass fill are maintained like lawns;

*Maintenance is similar to a conventional [[perennials|perennial]] planting bed;

*In the first 2 months water frequently (biweekly in the absence or rain) and as needed (e.g., bimonthly) over the remainder of the first growing season;

*Water bi-weekly in the absence of rain during first two months and as needed for the remainder of the first [[Climate Trends in Ontario|growing season]];

*Remove weeds and undesirable plants biannually to quarterly;

*Remove undesirable [[vegetation]] biannually to quarterly;

*Replace/reseed dead plantings annually to achieve 80% cover by the third growing season;

*Prune [[shrubs]] and [[trees]] annually, and replace dead [[plants]] to maintain a minimum of 80% cover by the third growing season.   

*Do not apply chemical fertilizers.   

|[[File:Veg Pass p.p.JPG|315px|thumb|center|The vegetation cover on the permeable pavement is turf grass as specified in the final design and contains very few weeds. (Photo source: WEF).]]  

|[[File:Veg Pass p.p.JPG|315px|thumb|center|The vegetation cover on the permeable pavement is turf grass as specified in the final design and contains very few weeds. (Photo source: WEF).]]  

|[[File:Veg Fail p.p.JPG|290px|thumb|center|The turf grass cover on the permeable walkway is not thriving in some areas and needs cutting in others. It is also impairing the aesthetic value of the BMP.]]  

|[[File:Veg Fail p.p.JPG|290px|thumb|center|The turf grass cover on the permeable walkway is not thriving in some areas and needs cutting in others. It is also impairing the aesthetic value of the BMP.]]  

|'''[[Overflow|Overflow Outlet]]'''

|'''[[Overflow|Overflow Outlet]]'''

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Structures (e.g., catchbasin, curb-cut, [[swale]]) that convey flow that exceeds the storage capacity of the BMP to another drainage system (e.g., municipal storm sewer or other BMP).  

Flows exceeding the storage capacity of the BMP are conveyed to an adjacent drainage system via an [[overflow|overflow outlet structure]] and the roof drainage system.

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*Remove trash, natural debris and clippings biannually to quarterly;

*Remove trash, debris and sediment biannually to quarterly.

|[[File:Overflow Pass p.p.JPG|320px|thumb|center|The overflow outlet is free of damage and obstruction and functions as designed to safely convey excess water from the BMP.]]  

|[[File:Overflow Pass p.p.JPG|320px|thumb|center|The overflow outlet is free of damage and obstruction and functions as designed to safely convey excess water from the BMP.]]  

|[[File:Overflow Fail p.p.JPG|280px|thumb|center|The overflow outlet is obstructed with sediment which impairs its function to convey excess water from the BMP.]]  

|[[File:Overflow Fail p.p.JPG|280px|thumb|center|The overflow outlet is obstructed with sediment which impairs its function to convey excess water from the BMP.]]  

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|'''[[Underdrain|Sub-drain]]'''

|'''[[Green roofs#Irrigation|Irrigation System]]'''

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Optional component; [[Pipes|perforated pipe(s)]] surrounded by [[gravel]] and may be wrapped in [[Geotextile|geotextile filter fabric]]; installed in the base or sub-base gravel layer to collect and convey treated water to an adjacent drainage system or other BMP; may also include a flow restrictor.

Most green roofs will require watering over their operating life cycle, especially during the first 2 months. Systems can range from simple hose bibs, garden hoses and sprinklers to intelligent automated systems that schedule watering based on weather forecasts and cistern water levels.  

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*Keep pipe and flow restrictor free of obstructions by flushing annually;

*In the spring, reconnect all parts to the water supply, flush lines to clear out any debris or sediment and test to confirm that the system is undamaged and functioning well;

*Inspect flow restrictor regularly (e.g., biannually to quarterly).

*In the late fall/early winter, disconnect the system from the water supply, connect it to an air compressor and blow air through it to remove water and ensure the lines and parts are dry, shut off water supply to the roof, and drain all hose bibs;

*Remove any debris/sediment accumulated on filters biannually.

|[[File:Underdrain Pass p.p.JPG|310px|thumb|center|The solid section of the sub-drain pipe is not obstructed by sediment, debris or roots and shows no signs of damage.]]  

|[[File:Underdrain Pass p.p.JPG|310px|thumb|center|The solid section of the sub-drain pipe is not obstructed by sediment, debris or roots and shows no signs of damage.]]  

|[[File:Underdrain Fail p.p.JPG|300px|thumb|center|A section of the sub-drain pipe has been crushed which substantially reduces its conveyance capacity]]  

|[[File:Underdrain Fail p.p.JPG|300px|thumb|center|A section of the sub-drain pipe has been crushed which substantially reduces its conveyance capacity]]  

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|'''[[Monitoring well]]'''

|'''[[Green roofs#Design|Protective layers]]'''

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[[Wells|Perforated standpipe]] that extends from the bottom of the excavation to just below the pavement surface and contains perforations or slots to allow [[Digital technologies|measurement of subsurface water level]]; used to track drainage performance over the operating life cycle of the BMP.

May be one or two layers; designed to protect the roof deck from water damage, including a waterproofing membrane, a root barrier that protects the water-proofing membrane from root penetration and degradation by microbial activity.

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*[[Wells|Standpipes]] should be securely capped on both ends and protected from damage by vehicular traffic by a casing.

*Repair isolated leaks in the water-proofing membrane through deconstruction of a small portion of the green roof, patching with new material, and reconstruction.

|[[File:Monitor Pass p.p.JPG|340px|thumb|center|The well is undamaged and accessible and the cap is in place and secured to prevent unauthorized access]]  

|[[File:Monitor Pass p.p.JPG|340px|thumb|center|The well is undamaged and accessible and the cap is in place and secured to prevent unauthorized access]]  

|[[File:Monitor Fail p.p.JPG|300px|thumb|center|The well cap is missing and the casing is clogged by sediment, preventing access for monitoring and allowing sediment to flow into the sub-drain system.]]  

|[[File:Monitor Fail p.p.JPG|300px|thumb|center|The well cap is missing and the casing is clogged by sediment, preventing access for monitoring and allowing sediment to flow into the sub-drain system.]]  

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