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Line 1: <table class="table table-striped"> </table></table>---- <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><gallery mode="packed" widths=300px heights=300px>Kitchener-8.jpg| Extended tree pit on Kings Street, Kitchener. </gallery></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>
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===Types of bioretention by underground design===
===Types of bioretention by underground design===
<table class = "table-responsive">
<table class="table table-striped table-responsive">
<tr class='success'>
<tr class ='success'><th>Type</th><th>Gravel layer</th><th>Underdrain</th><th>Liner</th><th>Mechanisms</th><th>Schematic</th></tr>
<th>Type</th>
<tr><td>[[Rain gardens]]</td><td>-</td><td>-</td><td>-</td><td>These are the simplest construction, often used by residents or community groups. Volume reduction is through infiltration and evapotranspiration. </td><td>[[File:Rain Garden Schematic.png]]</td></tr>
<th class="text-center">Gravel layer</th>
<th class="text-center">Underdrain</th>
<tr><td>[[Bioretention: Full infiltration|Infiltrating bioretention]]</td><td>yes</td><td>-</td><td>-</td><td>This is the most highly desirable type of bioretention where the soils permit infiltration at a great enough rate to empty the facility between storm events. Volume reduction is primarily through infiltration to the underlying soils, with some evapotranspiration. As there is no outflow from this BMP, it is particularly desirable in areas where nutrient management is a concern to the watershed.</td><td>[[File:Full infiltration.png]]</td></tr>
<th class="text-center">Liner</th>
<th>Mechanisms</th>
<tr><td>[[Bioretention: Partial infiltration|Partially infiltrating bioretention]]</td><td>yes</td><td>yes</td><td>-</td><td>Including an underdrain in the gravel storage layer ensures that the facility will empty between storm events even over ‘tight soils’. The drain discharges to a downstream point, which could be an underground infiltration facility. Limited volume reduction is gained through infiltration and evapotranspiration.</td><td>[[File:Partial infiltration.png]]</td></tr>
<th class="text-center">Schematic</th>
</tr>
<tr><td>[[Bioretention: Partial infiltration|Bioretention with storage]]</td><td>yes</td><td>yes</td><td>-</td><td>By raising the outlet of the discharge pipe the bottom portion of the BMP can only drain through infiltration. 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 use fresh wood mulch, which also fosters denitrifying biological processes. </td><td>[[File:Partial with storage.png]]</td></tr>
<tr>
<td>[[Rain gardens]]</td>
<tr><td>[[Bioretention: Non-infiltrating|Bioretention planters (non-infiltrating)]]</td><td>yes</td><td>yes</td><td>yes</td><td>This type may be required over contamination hot-spots or in very dense urban areas with a lot of other underground infrastructure. The design includes an impermeable base and sides, so that volume reduction is made only through evapotranspiration. This type of cell can be constructed above grade in any waterproof and structurally sound container, e.g. in cast concrete or a metal tank.</td><td>[[File:Planter.png]]</td></tr>
<td class="text-center">-</td>
<td class="text-center">-</td>
<td class="text-center">-</td>
<td>These are the simplest construction, often used by residents or community groups. Volume reduction is through infiltration and evapotranspiration. </td>
<td>[[File:Rain Garden Schematic.png]]</td>
</tr>
<tr>
<td>[[Bioretention: Full infiltration|Infiltrating bioretention]]</td>
<td class="text-center">yes</td>
<td class="text-center">-</td>
<td class="text-center">-</td>
<td>This is the most highly desirable type of bioretention where the soils permit infiltration at a great enough rate to empty the facility between storm events. Volume reduction is primarily through infiltration to the underlying soils, with some evapotranspiration. As there is no outflow from this BMP, it is particularly desirable in areas where nutrient management is a concern to the watershed.</td>
<td>[[File:Full infiltration.png]]</td>
</tr>
<tr>
<td>[[Bioretention: Partial infiltration|Partially infiltrating bioretention]]</td>
<td class="text-center">yes</td>
<td class="text-center">yes</td>
<td class="text-center">-</td>
<td>Including an underdrain in the gravel storage layer ensures that the facility will empty between storm events even over ‘tight soils’. The drain discharges to a downstream point, which could be an underground infiltration facility. Limited volume reduction is gained through infiltration and evapotranspiration.</td>
<td>[[File:Partial infiltration.png]]</td>
</tr>
<tr>
<td>[[Bioretention: Partial infiltration|Bioretention with storage]]</td>
<td class="text-center">yes</td>
<td class="text-center">yes</td>
<td class="text-center">-</td>
<td>By raising the outlet of the discharge pipe the bottom portion of the BMP can only drain through infiltration. 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 use fresh wood mulch, which also fosters denitrifying biological processes. </td>
<td>[[File:Partial with storage.png]]</td>
</tr>
<tr>
<td>[[Bioretention: Non-infiltrating|Bioretention planters (non-infiltrating)]]</td>
<td class="text-center">yes</td>
<td class="text-center">yes</td>
<td class="text-center">yes</td>
<td>This type may be required over contamination hot-spots or in very dense urban areas with a lot of other underground infrastructure. The design includes an impermeable base and sides, so that volume reduction is made only through evapotranspiration. This type of cell can be constructed above grade in any waterproof and structurally sound container, e.g. in cast concrete or a metal tank.</td>
<td>[[File:Planter.png]]</td>
</tr>
</table>
</table>