Changes

= A =

= A =

=== Aggregate ===

A broad category of particulate material used in construction, including sand,

<li>Aggregate: A broad category of particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates, and available in various particulate size gradations.</li>

gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates, and available in

various particulate size gradations.

 

 

= B =

= B =

=== Berm ===

A compacted earthen wall that diverts runoff or creates shallow ponding of runoff. In

<li>Berm: A compacted earthen wall that diverts runoff or creates shallow ponding of runoff. In some cases, runoff ponds behind the berm and gradually flows through it or is infiltrated.</li>

some cases, runoff ponds behind the berm and gradually flows through it or is infiltrated.

<li>Biofilter: A bioretention stormwater best management practice featuring an impermeable liner and underdrain that prevents infiltration of runoff into the underlying native soil; provides sedimentation and filtration of urban runoff as it passes through the mulch layer, engineered

 

filter media and vegetation root zone.</li>

=== Biofilter ===

<li>Bioretention: A stormwater filtration and infiltration practice. The practice is a shallow excavated surface depression containing a prepared soil mix, mulch, and planted with specially selected vegetation. The system is engineered to temporarily store runoff in the depression and gradually filters it through the mulch, filter media, and root zone. They remove pollutants from runoff through filtration in the soil and uptake by plant roots and can help to reduce runoff volume through evapotranspiration and infiltration.</li>

A bioretention stormwater best management practice featuring an impermeable liner

and underdrain that prevents infiltration of runoff into the underlying native soil; provides

sedimentation and filtration of urban runoff as it passes through the mulch layer, engineered

filter media and vegetation root zone.

 

=== Bioretention ===

A stormwater filtration and infiltration practice. The practice is a shallow

excavated surface depression containing a prepared soil mix, mulch, and planted with specially

selected vegetation. The system is engineered to temporarily store runoff in the depression and

gradually filters it through the mulch, engineered soil mix, and root zone. They remove

pollutants from runoff through filtration in the soil and uptake by plant roots and can help to

reduce runoff volume through evapotranspiration and infiltration.

 

 

= C =

= C =

=== Check Dam ===

Structures constructed of a non-erosive material, such as suitably sized

<li>Check dam: Structure constructed of a non-erosive material, such as suitably sized aggregate, wood, gabions, riprap, or concrete, used to slow runoff water to allow sedimentation, filtration, evapotranspiration, and infiltration into the underlying native soil. Can be employed in

aggregate, wood, gabions, riprap, or concrete, used to slow runoff water to allow sedimentation,

practices such as bioswales and enhanced grass swales.</li>

filtration, evapotranspiration, and infiltration into the underlying native soil. Can be employed in

<li>Cistern: Tank used to store rainwater (typically roof runoff) for later use.</li>

practices such as dry and enhanced grass swales.

 

=== Cistern ===

Tank used to store rainwater (typically roof runoff) for later use.

 

 

= D =

= D =

=== Depression Storage ===

A technique for incorporating shallow depressed areas into urban

<li>Depression Storage: A technique for incorporating shallow depressed areas into urban landscaped areas for storing and infiltrating runoff. Typically, depression storage areas are small and have limited capacity and limited duration of retention in order to address property owner concerns relating to insects, damage to structures and inconvenience of ponded water on their property.</li>

landscaped areas for storing and infiltrating runoff. Typically, depression storage areas are

<li>Detention: The temporary storage of stormwater to control discharge rates, and allow for sedimentation.</li>

small and have limited capacity and limited duration of retention in order to address property

<li>Drawdown time: The period between the maximum water level and the minimum level (dry weather or antecedent level).</li>

owner concerns relating to insects, damage to structures and inconvenience of ponded water on

<li>Dry swale: Linear bioretention cell designed to convey, treat and attenuate stormwater runoff. The engineered filter media soil mixture and vegetation slows the runoff water to allow sedimentation, filtration through the root zone, evapotranspiration, and infiltration into the

their property.

underlying native soil.</li>

 

=== Detention ===

The temporary storage of stormwater to control discharge rates, and allow for

sedimentation.

 

=== Drawdown Time ===

The period between the maximum water level and the minimum level (dryweather

or antecedent level).

 

=== Dry Swale ===

Linear bioretention cells designed to convey, treat and attenuate stormwater runoff;

The engineered filter media soil mixture and vegetation slows the runoff water to allow

sedimentation, filtration through the root zone, evapotranspiration, and infiltration into the

underlying native soil.

 

 

= E=

= E=

=== Evapotranspiration ===

The combined loss of water to the atmosphere from land and water

<li>Evapotranspiration; The combined loss of water to the atmosphere from land and water surfaces by evaporation and from plants by transpiration.</li>

surfaces by evaporation and from plants by transpiration.

<li>Enhanced grass swale: Vegetated open channels designed to convey, treat and attenuate stormwater runoff, also referred to as enhanced vegetated swales. Enhanced grass swales are not capable of providing the same water balance and water quality benefits as dry swales, as they lack the engineered soil media and storage capacity.</li>

 

<li>Environmental Impact Report (EIR): The evaluation of the possible effects that may arise from a proposed project on the environment, together consisting of the natural, social and economic aspects.</li>

=== Enhanced Grass Swale ===

<li>Exfiltration: Loss of water from a drainage system as a result of percolation or absorption into the surrounding medium (e.g., the infiltration of water into the native soil through a perforated pipe wall as it is conveyed).</li>

Vegetated open channels designed to convey, treat and attenuate

stormwater runoff, also referred to as enhanced vegetated swales. Enhanced grass swales are

not capable of providing the same water balance and water quality benefits as dry swales, as

they lack the engineered soil media and storage capacity.

 

=== Environmental Impact Report (EIR) ===

The evaluation of the possible effects that may arise from a

proposed project on the environment, together consisting of the natural, social and economic

aspects.

 

=== Exfiltration ===

Loss of water from a drainage system as a result of percolation or absorption into

the surrounding medium (e.g., the infiltration of water into the native soil through a perforated

pipe wall as it is conveyed).

 

 

= F =

= F =

=== Filter Media ===

The engineered soil bed component of bioretention cell or dry swale designs,

<li>Filter media: The engineered soil bed component of bioretention cell or dry swale designs, typically composed of a sandy soil mixture containing a limited proportion of fine textured material, which provides a growing medium for vegetation, maintains a high rate of infiltration over the lifespan of the practice, and retains contaminants through filtration and adsorption to soil particles.</li>

typically composed of a sandy soil mixture containing a limited proportion of fine textured

<li>Filtration: The technique of removing pollutants from runoff as it infiltrates through the soil.</li>

material, which provides a growing medium for vegetation, maintains a high rate of infiltration

<li>Fines: Soil materials with less than a 0.050 mm diameter particle size.</li>

over the lifespan of the practice, and retains contaminants through filtration and adsorption to

<li>First flush: Initial pulse of stormwater runoff which picks up the pollutants that have settled on surfaces during the dry period. The first flush contains the highest pollutant concentrations.</li>

soil particles.

<li>Forebay: A pretreatment basin at the inlet of a practice that allow settling out of sediment and associated contaminants suspended in urban runoff.</li>

 

<li>Flow path length: The minimum linear distance of water flow across a surface.</li>

=== Filtration ===

<li>Fluvial geomorphology: The study of the processes responsible for the shape and form, or morphology, of watercourses; describes the processes whereby sediment (e.g., silt, sand, gravel) and water are transported from the headwaters of a watershed to its mouth.</li>

The technique of removing pollutants from runoff as it infiltrates through the soil.

<li>Fused grid : A hybrid neighbourhood and district layout model that combines the geometries of inner city grid road patterns with the loop and cul-de-sac road patterns of conventional suburbs.</li>

 

=== Fines ===

Soil materials with less than a 0.050 mm diameter particle size.

 

=== First Flush ===

Initial pulse of stormwater runoff which picks up the pollutants that have settled on

surfaces during the dry period. The first flush contains the highest pollutant concentrations.

 

=== Forebay ===

A pretreatment basin at the inlet of a practice that allow settling out of sediment and

associated contaminants suspended in urban runoff.

 

=== Flow Path Length ===

The minimum linear distance of water flow across a surface.

 

=== Fluvial Geomorphology ===

The study of the processes responsible for the shape and form, or

morphology, of watercourses; describes the processes whereby sediment (e.g., silt, sand,

gravel) and water are transported from the headwaters of a watershed to its mouth.

 

=== Fused Grid ===

A hybrid neighbourhood and district layout model that combines the geometries of

inner city grid road patterns with the loop and cul-de-sac road patterns of conventional suburbs.

 

 

= G =

= G =

=== Grass Swales ===

Vegetated, open channels designed to convey, treat and attenuate runoff.

<li>Grass swales: Vegetated, open channels designed to convey, treat and attenuate runoff. Design variations range from simple grass channels, which are designed primarily for conveyance to more complex treatment and volume reduction designs like enhanced grass swales, and dry swales or bioswales.</li>

Design variations range from simple grass channels, which are designed primarily for

<li>Geotextile: A filter fabric that is installed to separate dissimilar soils and provide runoff filtration and contaminant removal benefits while maintaining a suitable rate of flow; may be used to prevent fine-textured soil from entering a coarse granular bed, or to prevent coarse granular from being compressed into underlying finer-textured soils.</li>

conveyance to more complex treatment and volume reduction designs like enhanced grass

<li>Granular: Gravel, or crushed stone of various size gradations (i.e., diameter), used in construction; void forming material used as bedding and runoff storage reservoirs and underdrains in stormwater infiltration practices.</li>

swales, and dry swales or bioswales.

<li>Gravel diaphragm: Is a level spreading device placed at a runoff discharge location, perpendicular to flow, to maintain sheet flow and distribute runoff as evenly as possible across a pervious area or stormwater infiltration practice. A gravel diaphragm acts as a pretreatment device, settling out suspended sediments before they reach the practice.</li>

 

<li>Green roof: A thin layer of vegetation and growing medium installed on top of a conventional flat or sloped roof, also referred to as living roofs or rooftop gardens.</li>

=== Geotextile ===

<li>Green infrastructure: Natural vegetation and vegetative technologies in urban settings such as: urban forests; green roofs; green walls; green spaces; rain gardens; bioswales; community gardens; natural and engineered wetlands and stormwater management ponds; and porous pavement systems. These systems are designed to provide multiple benefits, such as moderate temperatures, clean air and water, and improve aesthetics.</li>

A filter fabric that is installed to separate dissimilar soils and provide runoff filtration

<li>Groundwater discharge: The outflow of groundwater to a well, spring, wetland or watercourse.</li>

and contaminant removal benefits while maintaining a suitable rate of flow; may be used to

<li>Groundwater recharge: The inflow of surface water to a groundwater reservoir or aquifer.</li>

prevent fine-textured soil from entering a coarse granular bed, or to prevent coarse granular

from being compressed into underlying finer-textured soils.

 

=== Granular ===

Gravel, or crushed stone of various size gradations (i.e., diameter), used in

construction; void forming material used as bedding and runoff storage reservoirs and

underdrains in stormwater infiltration practices.

 

=== Gravel Diaphragm ===

Is a level spreading device placed at a runoff discharge location,

perpendicular to flow, to maintain sheet flow and distribute runoff as evenly as possible across a

pervious area or stormwater infiltration practice. A gravel diaphragm acts as a pretreatment

device, settling out suspended sediments before they reach the practice.

 

=== Green Roof ===

A thin layer of vegetation and growing medium installed on top of a conventional

flat or sloped roof, also referred to as living roofs or rooftop gardens.

 

=== Green Infrastructure ===

Natural vegetation and vegetative technologies in urban settings such as:

urban forests; green roofs; green walls; green spaces; rain gardens; bioswales; community

gardens; natural and engineered wetlands and stormwater management ponds; and porous

pavement systems. These systems are designed to provide multiple benefits, such as moderate

temperatures, clean air and water, and improve aesthetics.

 

=== Groundwater Discharge ===

The outflow of groundwater to a well, spring, wetland or watercourse.

 

=== Groundwater Recharge ===

The inflow of surface water to a groundwater reservoir or aquifer.

 

 

= H =

= H =

=== Hydraulic Conductivity ===

=== Hydraulic Conductivity ===