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Line 1: − + − + − + − + + + − ===Overview===+ + + + + + + + + + + + + + + + + − <p>Bioretention cells are one of the most well recognized form of Low Impact Development. They can encompass all mechanisms of action: infiltration, filtration and evapotranspiration. + − </p> + − {{TextBox|1=Bioretention cells are an ideal technology for: + − *Fitting functional vegetation into urban landscapes+ − *Treating runoff collected from nearby impervious surfaces}}+ + + − <p><strong>The fundamental components of a bioretention cell are:</strong>+ − *Biomedia: An engineered soil mix − *Planting − *Storage layer of coarse aggregate − <strong>Additional components may include:</strong> − *Under-drain to redistribute or remove excess water − *Impermeable membrane to prevent infiltration to soils below − </p> − </div>+ − <div class="col-md-4">+ + + + + + + + + − <panelSuccess>+ − <gallery mode="packed" widths=300px heights=300px>+ − Edwards Gardens Bio 2014.JPG| These bioretention cells at Edwards Gardens in Toronto receive inflow from hydraulically connected permeable paving. + − </gallery> − </panelSuccess> − + − <div class="col-md-12">+ + + − <table class = "table-responsive">+ − <table class="table table-striped">+ − <caption><strong>Types of bioretention cell</strong></caption>+ − <tr class ='success'><th>Form</th><th>Characteristics</th><th>Examples</th></tr>+ − <tr><td>Infiltrating Cells</td><td>Used in developments with large landscaping areas, parks, parking lot islands, or any areas without tight space constraints. They have side slopes ≥2:1. Often, they receive sheet flow, but in some cases they are surrounded by curbs and will have inlets. The distinction between these options will determine the recommended types of pre-treatment. </td><td>+ − <gallery mode="packed" widths=300px heights=300px>+ − IMG 2457 750X500.jpg| Bioretention cell capturing and treating runoff from adjacent parking lot at the Kortright Centre, Vaughan. </gallery></td></tr>+ − <tr><td>[[Rain Gardens]]</td><td>Often found on residential sites or on land managed by community organisations . This simple variation may be constructed by the property owner and usually excludes the storage layer. </td><td>See main article on rain gardens</td></tr>+ − <tr><td>Bioretention Planters (stormwater planters)</td><td>Typically used in ultra-urban areas adjacent to buildings and in plazas. They appear similar to traditional landscaped beds, but differ by receiving runoff from nearby surfaces.</td><td>Image here</td></tr>+ − <tr><td>Extended tree pits (parallel bioretention)</td><td>Located within the right-of-way, occupying the space between sidewalk and street. The inlets can be positioned on either or both sides, and are designed to prevent the system from filling beyond a fixed capacity. When ponding occurs, stormwater bypasses the inlets, making this a 'parallel' system rather than a flow-though or online design. </td><td>Image here</td></tr>+ − <tr><td>Curb extensions (bump outs)</td><td>Installed in road-right-of-way, these function as a stormwater facility and a traffic calming measure. Inlets are integrated into the raised concrete curb and receive flow from the street side.</td><td>Image here</td></tr>+ − </table>+ − </table>+ + + + + + + + + + + − ----+ + + + + + − + − </div>+ − <div class="col-md-8">+ − Planning Content+ + − </div>+ − <div class="col-md-4">+ + + − <panelSuccess>+ − <gallery mode="packed" widths=300px heights=300px>+ − IMG 2457 750X500.jpg| Bioretention cell capturing and treating runoff from adjacent parking lot at the Kortright Centre, Vaughan. + − </gallery>+ − </panelSuccess> − </div>+ − <div class="col-md-12">+ − + + + + + + + + + + + + + − ===Design===+ − </div> − <div class="col-md-8"> − Design Content − </div>+ − <div class="col-md-4">+ + + + + − <panelSuccess>+ − <gallery mode="packed" widths=300px heights=300px>+ − IMG 2457 750X500.jpg| Bioretention cell capturing and treating runoff from adjacent parking lot at the Kortright Centre, Vaughan. + − </gallery>+ − </panelSuccess>+ + + + + + − </div> − <div class="col-md-12"> − ---- − ===Performance=== − </div> − <div class="col-md-8"> − Performance Content − </div>+ − <div class="col-md-4"> − <panelSuccess>+ − <gallery mode="packed" widths=300px heights=300px>+ − IMG 2457 750X500.jpg| Bioretention cell capturing and treating runoff from adjacent parking lot at the Kortright Centre, Vaughan. + − </gallery>+ − </panelSuccess>+ + + + + + + + + + + + + + + + + + + + − </div>+ − <div class="col-md-12">+ − ---- − − <h4>In Ontario</h4> − <strong>City of Mississauga</strong><br> − The City of Mississauga has a stormwater management credit program which includes RWH as one of their recommended site strategies[https://www.mississauga.ca/portal/services/credit-program]. − <br> − <h4>LEED BD + C v. 4</h4> − <h4>SITES v.2 </h4>+ − + + + − + − + − + − + − + − + − + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + − + + + + + + + + − <table class="table table-hover table-condensed table-bordered"> − <td class="text-center"><i class="fa fa-envelope-open-o"></i> [[Special:SpecialContact|<strong>SEND US YOUR QUESTIONS & FEEDBACK ABOUT THIS PAGE</strong>]]</td> − </table> − − +
→Performance
This article is about planted installations designed to capture surface runoff through an engineered soil with subterranean infrastructure. <br>
[[File:Edwards Gardens Bio 2014.JPG|thumb|alt=This is alt text|These bioretention cells at Edwards Gardens in Toronto receive inflow from hydraulically connected permeable paving parking stalls]]
For simpler, residential systems, see [[Rain Gardens]]. <br>
[[File:IMG 2457 750X500.jpg|thumb|Bioretention cell capturing and treating runoff from an adjacent parking lot at the Kortright Centre, Vaughan.]]
For linear systems, which convey flow, but are otherwise similar see [[Swales|Bioswales]].
This article is about planted installations designed to capture and infiltrate some or all of the stormwater received.
<div class="col-md-8">
<br> For simple systems, without underdrains or storage reservoirs (typically found in residential settings), see [[Rain gardens]].
<br> For linear systems that have a gradually sloping filter media bed and convey flow, but are otherwise similar to bioretention, see [[Swales|Bioswales]].
<br> For planted systems that do not infiltrate water, see [[Stormwater planters]].
{{TOClimit|2}}
{{TOClimit|2}}
==Overview==
Bioretention systems may be the most well recognized form of [[low impact development]] (LID). They can fit into any style of landscape and utilize all of the stormwater treatment mechanisms: sedimentation, [[infiltration]], filtration, attenuation and [[evapotranspiration]].
{{textbox|Bioretention is an ideal technology for:
*Fitting multi-functional vegetation into urban landscapes
*Treating runoff collected from nearby impervious surfaces}}
'''The fundamental components of a bioretention cell are:'''
*[[Inlets| Inlets]] which may be curb openings (e.g. modified curbs, spillways), pipes, road or side inlet catchbasins, trench drains or other pre-fabricated inlet structures;
*A surface ponding area defined by landscaped side slopes or hardscape structures and the invert elevation of the overflow outlet structure;
*A filter bed containing [[Bioretention: Filter media| filter media]];
*A filter bed surface cover layer (e.g. [[mulch]] and [[stone]]);
*[[Plant lists|Plants]], and;
*An [[Overflow| overflow outlet]] to limit surface ponding and safely convey excess flow to a downstream storm sewer or the next BMP in the treatment train.
'''Additional components may include:'''
*An [[underdrain]] to redistribute or remove excess water and access structures or standpipes for periodic inspection and flushing;
*An [[Bioretention: Internal water storage| internal water storage reservoir]] composed of a [[reservoir aggregate]] layer, and may include embedded void-forming structures to minimize depth and conserve aggregate, and organic material derived from untreated wood (aids in dissolved nitrogen removal);
*[[Wells|Monitoring wells]] installed to the base and screened in the [[underdrain]] aggregate to verify and track [[Drainage time|drainage time]]; and
*Filter media [[additives]] intended to enhance retention of nutrients, metals, petroleum hydrocarbons and/or bacteria.
==Planning considerations==
''Note Site Considerations from the Bioretention Fact Sheet [https://sustainabletechnologies.ca/app/uploads/2013/02/Bioretention.pdf] in the 2010 CVC/TRCA LID Stormwater Management Planning Design are detailed below and within links included''
===Infiltration===
Some form of stormwater landscaping (bioretention) can be integrated into most spaces. Although there are some [[Infiltration#Constraints|constraints]] to infiltrating water, it is preferable to do so where possible.
Designing bioretention without an underdrain is highly desirable wherever the soils permit infiltration at a rate which is great enough to empty the facility between storm events. Volume reduction is achieved primarily through infiltration to the underlying soils, with some evapotranspiration. As there is no outflow from this BMP under normal operating conditions, it is particularly useful in areas where nutrient management is a concern to the watershed.
Bioretention with an [[underdrain]] is a popular choice in areas with 'tighter' soils where infiltration rates are < 15 mm/hr. Including a perforated [[pipe]] in the [[reservoir aggregate]] layer helps to empty the facility between storm events, which is particularly useful in areas with [[low permeability soils]]. The drain discharges to a downstream point, which could be an underground [[infiltration trench]] or [[chamber]] facility. Volume reduction is gained through infiltration and [[evapotranspiration]]. By raising the outlet of the discharge pipe the bottom portion of the BMP can only drain through infiltration, creating an [[Bioretention: Internal_water_storage| internal water storage reservoir]]. This creates a fluctuating anaerobic/aerobic environment which promotes denitrification. Increasing the period of storage has benefits for promoting infiltration, but also improves water quality for catchments impacted with nitrates. A complimentary technique is to include fresh wood mulch in the storage [[Reservoir aggregate| reservoir aggregate]], which fosters denitrifying biological processes.
Where infiltration is entirely impossible, but the design calls for planted landscaping, try a [[stormwater planter]] instead.
===Space===
*For optimal performance bioretention facilities should receive runoff from impervious drainage areas between 5 to 20 times their own permeable footprint surface area.
*In the conceptual design stage it is recommended to set aside approximately 10 - 20 % of the contributing drainage area for bioretention facility placement.
*Bioretention cells work best when distributed, so that no one facility receives runoff from more than 0.8 Ha, although there is a trade off to be considered regarding distributed collection and treatment versus ease of maintenance.
*Bioretention can be almost any shape, from having very curvilinear, soft edges with variable depth, to angular, hard-sided and uniform depth.
:For ease of construction and to ensure that the vegetation has adequate space, cells should be no narrower than 0.6 m at any point.
:The maximum width of a facility is determined by the reach of the construction machinery, which must not be tracked into the cell.
*Setback from buildings: A typical four (4) metre setback is recommended from building foundations. If an impermeable liner is used, no setback is needed.
*Proximity to underground utilities and overhead wires: Consult with local utility companies regarding horizontal and vertical clearance required between storm drains, ditches, and surface water bodies. Further, check whether the future tree canopy height in the bioretention area will not interfere with existing overhead wires.
The principles of bioretention can be applied in any scenario where planting or vegetation would normally be found.
===Private sites===
In single family residential sites [[Rain gardens|rain gardens]] most often take the form of a soft edged, traditional perennial planting bed.
As many private industrial, commercial and institutional sites have landscaping around their [[Bioretention: Parking lots| parking lots]], bioretention is an increasingly popular choice to manage stormwater in these contexts.
</div>
===Streetscape===
Bioretention is a popular choice for making urban green space work harder. Design configurations include extending the cells to accommodate shade trees, and using retrofit opportunities to create complete streets with traffic calming and curb extensions or 'bump outs'. See [[Bioretention: Streetscapes]]
===Parkland and natural areas===
Naturalized landscaping and soft edges can make a bioretention facility 'disappear' into green space surroundings. In some scenarios, a larger bioretention (50 - 800 m<sup>2</sup>) cell may be used as an end-of-pipe facility treating both sheet flow and concentrated flow before it enters an adjacent water course. In these larger installations care must be made in the design to distribute the inflow, preventing erosion and maximizing infiltration.
==Design==
{|class="wikitable"
|+ Optimizing bioretention for water quality
|-
!style="background: darkcyan; color: white"|Poor design choice: <br> Limits outflow water quality
!style="background: darkcyan; color: white"|Better design choice: <br> Improves outflow water quality
|-
|Single large cell design||Several smaller distributed or connected cells
|-
|Single concentrated inflow||Forebays or distributed flow
|-
|No pretreatment||Pretreatment provided as part of inlet design
|-
|Over-sized underdrain||Moderately sized underdrain (or no underdrain)
|-
|Filter bed < 0.5 m||Filter bed > 0.75 m
|-
|Filter media Plant-Available Phosphorus > 40 ppm||Filter media Plant-Available Phosphorus < 40 ppm
|-
|Filter media is predominantly sand||Filter media is a mixture of sand, topsoil and organic material
|-
|Surface covered with turf grass and stone||Surface covered with mulch and dense, deeply rooting vegetation
|}
===Sizing and Modelling===
Bioretention facilities should be sized to accommodate runoff from approximately 5 to 20 times the footprint area of the facility. i.e. they should have an I/P ratio of 5 to 20.
When the drainage area is too large, silt can accumulate very rapidly, overwhelm the [[pretreatment]] devices, and lead to clogging of the facility.
When the drainage area is relatively small compared to the bioretention facility, it can make the facility unreasonably costly.
*'''[[Bioretention: Sizing| Sizing]]'''
*'''[[Bioretention: TTT| Modelling]]'''
===Planning Considerations===
===Inlets and pretreatment options===
Options for [[pretreatment]] include:
*A [[level spreader]], [[gravel diaphragm]] or [[Vegetated filter strip]] for sheet flow
*A [[Forebays|forebay]] for concentrated surface flow
*An [[Oil and grit separators|oil and grit separator]] for concentrated underground flow
Simple (non-treating) [[inlets]] include:
*Sheet flow from a pavement edge or flush curb
*One of more [[curb cuts]]
*Covered drains
===Overflow routing===
{{:Overflow}}
===Plant Selection===
The nature of bioretention cells is to attenuate stormwater from rainfall events of varying intensities. For this reason, the vegetation used must be suitable for the varying moisture conditions and is often categorized into three zones related to the grading of the feature.
#'''Low Zone''' -- This area is frequently inundated during storm events, and is well-drained between rainfall events.
#*Mineral Meadow Marsh plant community.
----
#*Grasses, sedges, rushes, wildflowers, ferns and shrubs that have an ‘obligate’ to ‘facultative’ designation.
#*Wetland 'obligate' species that are flood tolerant as they will persist in average years and flourish in wetter years.
#*Plants that are likely to occur in wetlands or adjacent to wetlands.
#*Plants with dense root structure and /or vegetative cover are favoured for their ability to act as pollution filters and tendency to slow water velocity.
#*Be advised these practices are not constructed wetlands and are designed to fully drain within 48 hours.
#'''Mid Zone''' -- This zone is inundated less frequently (2 – 100 year storm events) and has periodically high levels of moisture in the soil. The ecology of this zone is a transition from the Mineral Meadow Marsh/Beach-type community to an upland community.
#*Plants able to survive in soils that are seasonally saturated, yet can also tolerate periodic drought.
#*Species include grasses and groundcovers, as well as low shrub species.
#'''High Zone''' -- The ecology of this zone is terrestrial due to its elevation in relation to the filter bed. The zone most closely resembles a Cultural Meadow or a Cultural Thicket community, depending on the mix of grasses, herbaceous material, shrubs and trees utilized.
#*Plants should have deep roots for structure, be drought-tolerant and capable of withstanding occasional soil saturation.
#*Trees and large shrubs planted in this zone will aid in the infiltration and absorption of stormwater.
#*This area can be considered a transition area into other landscape or site areas.
#*A variety (min. five) species should be used to avoid monocultures.
Exposure to roadway or parking lot runoff must be considered.
#Exposure to roadway or parking lot runoff
#*Select salt tolerant grasses, other herbaceous material and shrubs.
#*These can take on several forms, including parking lot islands, traffic islands, roundabouts, or cul-de-sacs and are often used as snow storage locations.
#No exposure to roadway or parking lot runoff
#*Practices allow for a greater range of species selection.
#*These receive runoff from rooftops or areas that use no deicing salt and have low pollutant exposure, such as courtyard bioretention.
Other selection factors:
*Most bioretention cells will be situated to receive full sun exposure. The ‘Exposure’ column in the [[Plant lists| plant lists]] identifies the sun exposure condition for each species.
*Facilities with a deeper filter media bed (e.g., 1 m) provide the opportunity for a wider range of plant species (including trees).
*The inclusion of vegetation with a variety of moisture tolerances ensures that the bioretention cell will adapt to a variety of weather conditions.
*Proper spacing must be provided for above-ground and below-ground utilities, and adjacent infrastructure.
*Where possible, a combination of native trees, shrubs, and perennial herbaceous materials should be used.
*A planting mix with evergreen and woody plants will provide appealing textures and colors year round, but are not appropriate for areas where snow will be stored/piled during winter.
*In areas where less maintenance will be provided and where trash accumulation in shrubbery or herbaceous plants is a concern, consider a “turf and trees” landscaping model.
*If trees are to be used, or the bioretention is located in a shaded location, then ensure that the chosen herbaceous plants are shade tolerant.
*Spaces for herbaceous flowering plants can be included. This may be attractive at a community entrance location or in a residential rain garden.
Tables for identifying ideal species for bioretention are found in the [[Plant lists]]. See [[plant selection]] and [[planting design]] for supporting advice.
==Performance==
{|class="wikitable"
|+Ability of Bioretention to Meet Stormwater Management Objectives
|-
!BMP
!Water Balance
!Water Quality
!Erosion Control
|-
|'''Bioretention with no underdrain'''
|Yes
|Yes-size for water quality storage requirement
|Partial-based on available storage volume and native soil infiltration rate
|-
|'''Bioretention with underdrain'''
|Partial-based on available storage volume beneath the underdrain and soil infiltration rate
|Yes-size for water quality storage requirement
|Partial-based on available storage volume beneath the underdrain and soil infiltration rate
|-
|'''Bioretention with underdrain and impermeable liner'''
|Partial-some volume reduction through evapotranspiration
|Yes-size for water quality storage requirement
|Partial-some volume reduction through evapotranspiration
|}
===Water Balance===
Bioretention has been shown to reduce runoff volume through evapotranspiration and infiltration of runoff. The research can be classified into bioretention applications that include underdrains and those that do not (and therefore rely on full infiltration into underlying soils). Aside from the underdrain, many other factors can impact the water balance
===Incentives and Credits===
Aside from the underdrain, many other factors can impact the water balance performance of a bioretention installation:
----
* Native soil infiltration rate;
* Rainfall patterns; and,
* Various sizing criteria on a per-installation basis.
===See Also===
{|class="wikitable"
<ul>
|+Volumetric runoff reduction from Bioretention
<li>[[Swales|Bioswales]]</li>
|-
<li>[[Rain Gardens]]</li>
!'''LID Practice'''
<li>[[Trees]]</li>
!'''Location'''
</ul>
!'''<u><span title="Note: Runoff reduction estimates are based on differences in runoff volume between the practice and a conventional impervious surface over the period of monitoring." >% Runoff Reduction*</span></u>'''
----
!'''Reference'''
|-
|rowspan="3" style="text-align: center;" | Bioretention without underdrain
|style="text-align: center;" |Connecticut
|style="text-align: center;" |99%
|style="text-align: center;" |Dietz and Clausen(2005)<ref>Dietz, M.E. and Clausen, J.C. 2005. A field evaluation of rain garden flow and pollutant treatment. Water, Air, and Soil Pollution, 167(1), pp.123-138. https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.365.9417&rep=rep1&type=pdf.</ref>
|-
|style="text-align: center;" |Pennsylvania
|style="text-align: center;" |80%
|style="text-align: center;" |Ermilio (2005)<ref>Ermilio, J. 2005. Characterization study of a bio-infiltration stormwater BMP. M.S. Thesis. Villanova University. Department of Civil and Environmental Engineering. Philadelphia, PA. https://www1.villanova.edu/content/dam/villanova/engineering/vcase/vusp/Ermilio-Thesis06.pdf.</ref>
|-
|style="text-align: center;" |Pennsylvania
|style="text-align: center;" |70%
|style="text-align: center;" |Emerson and Traver (2004)<ref>Emerson, C. and Traver, R. 2004. The Villanova Bio-infiltration Traffic Island: Project Overview. Proceedings of 2004 World Water and Environmental Resources Congress
(EWRI/ASCE). Salt Lake City, Utah, June 22 – July 1, 2004. https://ascelibrary.org/doi/abs/10.1061/40737(2004)38.</ref>
|-
|rowspan="10" style="text-align: center;" | Bioretention with underdrain
|-
|style="text-align: center;" |Vaughan, Ontario
|style="text-align: center;" |'''<u><span title="Note: Runoff reduction estimates are based on differences in runoff volume between the practice and a conventional impervious surface over the period of monitoring.">45%*</span></u>'''
|style="text-align: center;" |<span class="plainlinks">[https://sustainabletechnologies.ca/app/uploads/2016/02/KPP-Ext_FinalReport_Dec2015.pdf Van Seters and Drake (2015)]</span>
|-
|style="text-align: center;" |North Carolina
|style="text-align: center;" |98 to 99%
|style="text-align: center;" |Collins et al. (2008)<ref>Collins, K., W. Hunt and J. Hathaway. 2008. Hydrologic comparison of four types of permeable pavement and standard asphalt in eastern North Carolina. Journal of Hydrologic Engineering. </ref>
|-
|style="text-align: center;" |United Kingdom
|style="text-align: center;" |50%
|style="text-align: center;" |Jefferies (2004)<ref>Jefferies, C. 2004. Sustainable drainage systems in Scotland: the monitoring
programme. Scottish Universities SUDS Monitoring Project. Dundee, Scotland</ref>
|-
|style="text-align: center;" |United Kingdom
|style="text-align: center;" |53 to 66%
|style="text-align: center;" |Pratt ''et al.'' (1995)<ref>Pratt, C.J., Mantle, J.D.G., Schofield, P.A. 1995. UK research into the performance of permeable pavement reservoir structures in controlling stormwater discharge quantity and quality. Water Science Technology. Vol. 32. No. 1. pp. 63-69.</ref>
|-
|style="text-align: center;" |Maryland
|style="text-align: center;" |45% to 60%
|style="text-align: center;" |Schueler ''et al.'' (1987)<ref>Schueler, T. 1987. Controlling urban runoff: a practical manual for planning and designing urban BMPs. Metropolitan Washington Council of Governments. Washington, DC. </ref>
|-
|style="text-align: center;" |Mississauga
|style="text-align: center;" |61 to 99%
|style="text-align: center;" |<span class="plainlinks">[https://cvc.ca/wp-content/uploads/2018/05/IMAX-Low-Impact-Development-Monitoring-Case-Study-may-24.pdf CVC (2018)]</span>
|-
|style="text-align: center;" |Montreal
|style="text-align: center;" |26 to 98%
|style="text-align: center;" |Vaillancourt ''et al.'' (2019) <ref>Vaillancourt, C., Duchesne, S., & Pelletier, G. 2019. Hydrologic performance of permeable pavement as an adaptive measure in urban areas: case studies near Montreal, Canada. Journal of Hydrologic Engineering, 24(8), 05019020.</ref>
|-
|style="text-align: center;" |Northern Ohio
|style="text-align: center;" |16 to 99%
|style="text-align: center;" |Winston ''et al.'' (2015) <ref>Winston, R. J., Dorsey, J. D., & Hunt, W. F. (2015). Monitoring the performance of bioretention and permeable pavement stormwater controls in Northern Ohio: hydrology, water quality, and maintenance needs. Chagrin River Watershed Partners. Inc. under NOAA award No. NA09NOS4190153.</ref>
|-
|style="text-align: center;" |Seoul, Korea
|style="text-align: center;" |30 to 65%
|style="text-align: center;" |Shafique ''et al.'' (2018) <ref>Shafique, M., Kim, R. and Kyung-Ho, K., 2018. Rainfall runoff mitigation by retrofitted permeable pavement in an urban area. Sustainability, 10(4), p.1231.</ref>
|-
| colspan="2" style="text-align: center;" |'''<u><span title="Note: This estimate is provided only for the purpose of initial screening of LID practices suitable for achieving stormwater management objectives and targets. Performance of individual facilities will vary depending on site specific contexts and facility design parameters and should be estimated as part of the design process and submitted with other documentation for review by the approval authority." >Runoff Reduction Estimate*</span></u>'''
|colspan="2" style="text-align: center;" |'''85% without underdrain;'''
'''45% with underdrain'''
|-
|}
===External Links===
==See also==
*[[Bioswales]]
*[[Rain gardens]]
*[[Trees]]
==External links==
*[https://store.csagroup.org/?cclcl=en_US/ CSA W200-18 Design of Bioretention Systems (2018) CSA Group]
*[https://store.csagroup.org/?cclcl=en_US/ CSA W201-18 Construction of Bioretention Systems (2018) CSA Group]
*[https://hlw.org.au/download/bioretention-technical-design-guidelines/ Bioretention Design Guidelines (2014) Healthy Waterways (Australia)]
----
----
[[Category:Infiltration]]
[[Category:Infiltration]]
[[Category:Planted]]
[[Category:Green infrastructure]]