# Difference between revisions of "Notation"

From LID SWM Planning and Design Guide

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+ | ;A<sub>c</sub> | ||

+ | :Area of the catchment, whole contributing drainage area (usually in m<sup>2</sup>) | ||

+ | |||

+ | ;A<sub>p</sub> | ||

+ | :Area of the practice e.g. footprint area of a bioretention cell (usually in m<sup>2</sup>) | ||

;d | ;d | ||

Line 11: | Line 16: | ||

;m | ;m | ||

:run of side slopes in channel cross sections (length, but usually expressed as a ratio in relation to rise. e.g. where side side slopes = 1:3.5, m = 3.5) | :run of side slopes in channel cross sections (length, but usually expressed as a ratio in relation to rise. e.g. where side side slopes = 1:3.5, m = 3.5) | ||

+ | |||

+ | ;n | ||

+ | :Manning's coefficient (unitless) (Note: for clarity porosity is being expressed as 'void ratio' and sharing the notation ' | ||

;q | ;q | ||

Line 25: | Line 33: | ||

;RVC<sub>T</sub> | ;RVC<sub>T</sub> | ||

− | :Runoff volume control target (as outlined | + | :Runoff volume control target (as outlined by MOECC, units are mm) |

;S | ;S | ||

Line 32: | Line 40: | ||

;SCF | ;SCF | ||

:Safety correction factor (dimensionless) | :Safety correction factor (dimensionless) | ||

+ | |||

+ | ;V<sub>R</sub> | ||

+ | :Void ratio, as usually applied to aggregates and yard materials. In this guide, is also applied to native soils in lieu of porosity (similarly dimensionless) | ||

;y | ;y | ||

:Depth of water (length, usually m or sometimes mm) | :Depth of water (length, usually m or sometimes mm) |

## Revision as of 00:39, 29 September 2017

- A
_{c} - Area of the catchmentThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale., whole contributing drainage areaThe total surface area upstream of a point on a stream that drains toward that point. Not to be confused with watershed. The drainage area may include one or more watersheds. (usually in m
^{2})

- A
_{p} - Area of the practice e.g. footprint area of a bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. cell (usually in m
^{2})

- d
- Depth e.g. of an infiltration practice (units of length, usually m)

- f
- Eh?

- L
- Length, e.g. of a reach, channel or swaleA shallow constructed channel, often grass-lined, which is used as an alternative to curb and channel, or as a pretreatment to other measures. Swales are generally characterized by a broad top width to depth ratio and gentle grades. (usually in m)

- m
- run of side slopes in channel cross sections (length, but usually expressed as a ratio in relation to rise. e.g. where side side slopes = 1:3.5, m = 3.5)

- n
- Manning's coefficient (unitless) (Note: for clarity porosityThe porosity (n) of a mixture is the ratio of the volume of void-space to the total or bulk volume of the mixture. It is closely related to the concept of void ratio (e) where void ratio is the ratio of the volume of void-space to the volume of solids. n = Volume of voids/Total volume of mixture = e/(1+e) is being expressed as 'void ratioThe void ratio (e) of a mixture is the ratio of the volume of void-space to the volume of solids. It is closely related to the concept of porosity (n) where porosity is the ratio of the volume of void-space to the total or bulk volume of the mixture. e = Volume of voids/Volume of solids = n/(1-n)' and sharing the notation '

- q
- infiltration rateThe rate at which stormwater percolates into the subsoil measured in inches per hour. in (length per time, usually mm/hr) (before or after application of safety factor?)

- Q
_{p} - Peak flow in units of volume per time (e.g. m
^{3}/s)

- R
_{a} - Existing rise of swaleA shallow constructed channel, often grass-lined, which is used as an alternative to curb and channel, or as a pretreatment to other measures. Swales are generally characterized by a broad top width to depth ratio and gentle grades. gradient (length, usually m)

- R
_{b} - Rise of compensation gradient for an enhanced swaleVegetated open channel, with check dams; designed to convey, treat and attenuate stormwater runoff. (length, usually m)

- RVC
_{T} - RunoffThat potion of the water precipitated onto a catchment area, which flows as surface discharge from the catchment area past a specified point.Water from rain, snow melt, or irrigation that flows over the land surface. volume control target (as outlined by MOECC, units are mm)

- S
- Slope

- SCF
- Safety correction factor (dimensionless)

- V
_{R} - Void ratioThe void ratio (e) of a mixture is the ratio of the volume of void-space to the volume of solids. It is closely related to the concept of porosity (n) where porosity is the ratio of the volume of void-space to the total or bulk volume of the mixture. e = Volume of voids/Volume of solids = n/(1-n), as usually applied to aggregatesA 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. and yard materials. In this guide, is also applied to native soils in lieu of porosityThe porosity (n) of a mixture is the ratio of the volume of void-space to the total or bulk volume of the mixture. It is closely related to the concept of void ratio (e) where void ratio is the ratio of the volume of void-space to the volume of solids. n = Volume of voids/Total volume of mixture = e/(1+e) (similarly dimensionless)

- y
- Depth of water (length, usually m or sometimes mm)