Changes

==Overview==

==Overview==

Given that [[Bioretention]] is a widely used name and a general "catch-all" term for most vegetated LID practices that temporarily store stormwater runoff in depressed planting beds there are a number of configurations of the feature that can be used in various contexts and environments. Depending on native soil infiltration rate and physical constraints, the facility may be designed without an [[underdrain]] for [[Bioretention: Full infiltration|full infiltration]], with an underdrain for [[Bioretention: Partial infiltration|partial infiltration]], or with an impermeable [[liner]] and underdrain for [[Stormwater planters|no infiltration/filtration only]] (i.e., a [[stormwater planters]] or biofilter) design. STEP has prepared life cycle costs estimates for each design configuration, based on a 2,000 m² asphalt drainage area, runoff control target of 25 mm depth and 72 hour drainage period, for comparison which can be viewed below. To generate your own life cycle cost estimates customized to the development context, design criteria, and constraints applicable to your site, access the updated [https://sustainabletechnologies.ca/lid-lcct/ LID Life Cycle Costing Tool (LCCT) here].

[[Infiltration trenches]] (also referred to as ‘infiltration galleries’) are design variations that consist of linear, rectangular or trapezoidal shape, with a bottom generally between 0.6 and 2.4 m wide. Linear trench geometries will drain faster than round or square shapes due to their larger perimeters. These geotextile-lined excavation facilities should have a nearly level or gently sloping bottom grade to spread flow evenly. Similar to soakaways, they are also filled with [[stone]] or other void-forming structures. They are well suited to sites where available space for infiltration is limited to strips of land between buildings or properties, or along road right-of-ways.  

STEP has prepared life cycle costs estimates for each design configuration, based on a 2,000 m² asphalt drainage area, runoff control target of 25 mm depth and 72 hour drainage period, for comparison which can be viewed below. To generate your own life cycle cost estimates customized to the development context, design criteria, and constraints applicable to your site, access the updated [https://sustainabletechnologies.ca/lid-lcct/ LID Life Cycle Costing Tool (LCCT) here].

==Design Assumptions==

==Design Assumptions==