Difference between revisions of "Site assessment of residential"

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m (Jenny Hill moved page Site Conditions Residential to Site conditions: Residential: Title styling)
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Having a comprehensive understanding of site conditions is critical for [[Screening LID Options]]
Having a comprehensive understanding of site conditions is critical for [[Screening LID Options]]
 
== Desktop Analysis of Background Information ==
 
A thorough assessment of background information is critical to understanding site conditions for residential lots or neighborhood. As you begin gathering and reviewing background information, determine any existing infrastructure gaps and planned upgrades, resident concerns, previous community greening efforts, water usage and basement flooding. The following should be considered when conducting a desktop analysis:
=== Desktop Analysis of Background Information ===
A thorough assessment of background information is critical to understanding site conditions for residential lots or neighborhood. As you begin gathering and reviewing the noted background information, it is also important to determine any existing infrastructure gaps and planned upgrades, resident concerns, community greening, water usage and basement flooding. The following information should be considered to conduct a desktop analysis of background information
 
 
 
* Watershed studies,  
* Watershed studies,  
* subwatershed studies,
* Subwatershed studies,
* stormwater master plans
* Stormwater master plans
* Sewershed delineation  
* Sewershed delineation  
* Areas of identified storm sewer capacity issues
* Areas with identified storm sewer capacity issues
* Area contributing to combined sewer overflows  
* Area contributing to combined sewer overflows  
* Areas of degraded water quality  
* Areas of degraded water quality  
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* The impact of planned development on existing infrastructure and watershed health
* The impact of planned development on existing infrastructure and watershed health
* Source water protection plans  
* Source water protection plans  
* Well head protection areas (quantity and quality)
* Wellhead protection areas (quantity and quality)
* Surficial Geology
* Surficial Geology
** Soil characterization
** Soil characterization
** Groundwater levels
** Groundwater levels
* Applicable Bylaws
In addition, be sure to know the relevant local bylaws. Construction some LID features may contravene local regulations. Below are some examples of typical bylaws and their potential impact on LID planning:
 
 
 
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General Provisions May Include
General Provisions May Include:


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Impacts on LID Options
Impacts on LID Options:


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Nuisance weeds and tall grass by-law
Nuisance weeds and tall grass  


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Designates tall grass and weeds as a public nuisance
Designates tall grass and weeds as a public nuisance


* Defines “tall grass” as grasses over a maximum height (typically 20 - 30
* Defines “tall grass” as grasses over a maximum height (typically 20 30 cm)
 
centimeters)


* Requires tall grass to be cut to a height not exceeding the maximum
* Requires tall grass to be cut to a height not exceeding the maximum
* Requires all nuisance weeds and weed seeds to be removed from a
* Requires all nuisance weeds and weed seeds to be removed from a property by the owner.
* property by the owner.
* The municipality may carry out the work to bring properties into
* The municipality may carry out the work to bring properties into
* compliance and recover the cost from the land owner
* Compliance and recovery costs from the land owner


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Vegetated LID practices (specifically those with prairie or ornamental grasses) an landscape naturalization may be in violation of this existing by-law
Vegetated LID practices may be in violation of the relevant bylaw, e.g. landscape naturalization with prairie or ornamental grasses.


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Property standards by-laws
Property standards  


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Sets minimum requirements for privately owned properties
Sets minimum requirements for privately owned properties


* Restricts low lying areas including those that have been excavated that
* Restricts low-lying areas, including those that have been excavated and accumulate water, and requires that they be drained, filled and graded so that water drains to a storm sewer or ditch.
* accumulate water, and directs them such that they be drained, filled and
* Requires that all landscaped areas be cut and maintained in a reasonable condition relative to the neighboring environment
* graded so that water drains to a storm sewer or ditch.
* Requires that all landscaped areas be cut and maintained in a reasonable
* condition in relation to the neighboring environment


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Can preclude the implementation LID practices such as bioretention facilities as they are designed be both low lying
Can preclude the some LID practices, such as bioretention facilities designed be both low-lying and including ‘shallow’ surface ponding. Such bylaws can also prohibit other BMPS which rely on naturalizing landscapes.
 
and include ‘shallow’ surface ponding.
 
May be considered prohibitive for the implementation naturalized landscape approach


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Sewer use by-laws
Sewer use  


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Although generally limited to sanitary sewers, many municipalities now include storm water within this by-law. It generally requires all storm water
Although generally limited to sanitary sewers, many municipalities now include storm water within this by-law. It generally requires all storm water be discharged to an approved outlet and regulates the contents of the discharged water.
 
to be discharged to an approved outlet and regulates the constituents of the discharged water.


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May not permit direct discharge of roof water to the municipal storm sewer system. This may include overflow from rainwater harvesting tanks and other
May not permit direct discharge of roof water to the municipal storm sewer system. This can include overflow from rainwater harvesting tanks and similar devices.
 
such devices


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Standing water by-law
Standing water


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* Often in response to mosquito breeding and West Nile Virus concerns.
* Often in response to mosquito breeding and West Nile Virus concerns.
* Accumulation is typically defined per a determined period of time (e.g. 48 hours)
* Accumulation is typically defined by a determined period of time (e.g. 48 hours)


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May be interpreted as prohibitive for soakaways subsurface storage facilities, bioretention, and bioswales
Soakaways, subsurface storage facilities, bioretention and bioswales may be prohibited.


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Boulevard planting by-laws
Boulevard planting


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May inhibit bio-swales or vegetated swales due to plant type and height restrictions of planting along municipal boulevards.
Bio-swales or vegetated swales may be constrained by plant-type and plant-height restrictions along municipal boulevards


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Roof Leader policies (often as part of property standards by-laws
Roof leader policies (often part of property standards bylaws)


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Regulates the collection and allowable discharge location of roof drainage
Regulates the collection and allowable discharge location of roof drainage


* May specify outlet distance from building foundation
* May specify outlet distance from building foundation and may prohibit discharge to storm sewers, impervious surfaces and property boundaries
* May prohibit discharge to storm sewers, impervious surfaces and property boundaries


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Progressive roof leader policies can encourage the implementation of rain gardens, soakaways, rain barrels, and other LID practices
Progressive roof leader policies can encourage the implementation of rain gardens, soakaways, rain barrels, and other LID practices.


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After concluding a desktop analysis, visiting the neighbourhood in question for field reconnaissance may be ideal. Be sure to look for:
 
* Neighbourhood characteristics – general impressions
 
 
 
 
 
Field Reconnaissance
 
 
 
* Neighbourhood characteristics
* General lot characteristics
* General lot characteristics
** % of property coverage by house
** % of property coverage by house
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** % of property covered by alternative landscaping
** % of property covered by alternative landscaping
** % of property covered by trees
** % of property covered by trees
** Location and general condtion of gardens
** Location and general condition of gardens
** Distribution and coverage of natural vegetation
** Distribution and coverage of natural vegetation
** Location of septic systems
** Location of septic systems
** Location and style off fencing
** Fencing style and location
** Prevalence of irrigation systems
** Prevalence of irrigation systems
** roadside swales
** Roadside swales
** % cur
** % curb
* Drainage characteristics
* Drainage characteristics
* Rooftop / drainage characteristics
* Rooftop / drainage characteristics
* Best management practices info
* Best management practices info
* Recommended actions
 
Once the analysis is complete, proceed to developing a list of recommended actions.

Revision as of 17:59, 1 December 2017

Having a comprehensive understanding of site conditions is critical for Screening LID Options

Desktop Analysis of Background Information[edit]

A thorough assessment of background information is critical to understanding site conditions for residential lots or neighborhood. As you begin gathering and reviewing background information, determine any existing infrastructure gaps and planned upgrades, resident concerns, previous community greening efforts, water usage and basement flooding. The following should be considered when conducting a desktop analysis:

  • Watershed studies,
  • Subwatershed studies,
  • Stormwater master plans
  • Sewershed delineation
  • Areas with identified storm sewer capacity issues
  • Area contributing to combined sewer overflows
  • Areas of degraded water quality
  • Areas prone to flooding (both urban and riverine)
  • Water quality targets
  • Flow targets
  • Infiltration targets
  • The impact of planned development on existing infrastructure and watershed health
  • Source water protection plans
  • Wellhead protection areas (quantity and quality)
  • Surficial Geology
    • Soil characterization
    • Groundwater levels

In addition, be sure to know the relevant local bylaws. Construction some LID features may contravene local regulations. Below are some examples of typical bylaws and their potential impact on LID planning:

Typical Bylaws

General Provisions May Include:

Impacts on LID Options:

Nuisance weeds and tall grass

Designates tall grass and weeds as a public nuisance

  • Defines “tall grass” as grasses over a maximum height (typically 20 – 30 cm)
  • Requires tall grass to be cut to a height not exceeding the maximum
  • Requires all nuisance weeds and weed seeds to be removed from a property by the owner.
  • The municipality may carry out the work to bring properties into
  • Compliance and recovery costs from the land owner

Vegetated LID practices may be in violation of the relevant bylaw, e.g. landscape naturalization with prairie or ornamental grasses.

Property standards

Sets minimum requirements for privately owned properties

  • Restricts low-lying areas, including those that have been excavated and accumulate water, and requires that they be drained, filled and graded so that water drains to a storm sewer or ditch.
  • Requires that all landscaped areas be cut and maintained in a reasonable condition relative to the neighboring environment

Can preclude the some LID practices, such as bioretention facilities designed be both low-lying and including ‘shallow’ surface ponding. Such bylaws can also prohibit other BMPS which rely on naturalizing landscapes.

Sewer use

Although generally limited to sanitary sewers, many municipalities now include storm water within this by-law. It generally requires all storm water be discharged to an approved outlet and regulates the contents of the discharged water.

May not permit direct discharge of roof water to the municipal storm sewer system. This can include overflow from rainwater harvesting tanks and similar devices.

Standing water

Prevents accumulation of water on an individual property within any depression

  • Often in response to mosquito breeding and West Nile Virus concerns.
  • Accumulation is typically defined by a determined period of time (e.g. 48 hours)

Soakaways, subsurface storage facilities, bioretention and bioswales may be prohibited.

Boulevard planting

Regulates the type of vegetation that can be planted within the boulevard area

Bio-swales or vegetated swales may be constrained by plant-type and plant-height restrictions along municipal boulevards

Roof leader policies (often part of property standards bylaws)

Regulates the collection and allowable discharge location of roof drainage

  • May specify outlet distance from building foundation and may prohibit discharge to storm sewers, impervious surfaces and property boundaries

Progressive roof leader policies can encourage the implementation of rain gardens, soakaways, rain barrels, and other LID practices.

After concluding a desktop analysis, visiting the neighbourhood in question for field reconnaissance may be ideal. Be sure to look for:

  • Neighbourhood characteristics – general impressions
  • General lot characteristics
    • % of property coverage by house
    • Driveway sizes
    • Drivway types (% of asphalt, gravel, block pavers, etc.)
    • % of property covered by turf
    • % of property covered by alternative landscaping
    • % of property covered by trees
    • Location and general condition of gardens
    • Distribution and coverage of natural vegetation
    • Location of septic systems
    • Fencing style and location
    • Prevalence of irrigation systems
    • Roadside swales
    • % curb
  • Drainage characteristics
  • Rooftop / drainage characteristics
  • Best management practices info

Once the analysis is complete, proceed to developing a list of recommended actions.