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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Revision as of 20:32, 18 September 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 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,
  • subwatershed studies,
  • stormwater master plans
  • Sewershed delineation
  • Areas of 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
  • Well head protection areas (quantity and quality)
  • Surficial Geology
    • Soil characterization
    • Groundwater levels
  • Applicable Bylaws


Typical Bylaws

General Provisions May Include

Impacts on LID Options

Nuisance weeds and tall grass by-law

Designates tall grass and weeds as a public nuisance

  • Defines “tall grass” as grasses over a maximum height (typically 20 - 30

centimeters)

  • 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 recover the cost from the land owner

Vegetated LID practices (specifically those with prairie or ornamental grasses) an landscape naturalization may be in violation of this existing by-law

Property standards by-laws

Sets minimum requirements for privately owned properties

  • Restricts low lying areas including those that have been excavated that
  • accumulate water, and directs them such 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 in relation to the neighboring environment

Can preclude the implementation LID practices such as bioretention facilities as they are designed be both low lying

and include ‘shallow’ surface ponding.

May be considered prohibitive for the implementation naturalized landscape approach

Sewer use by-laws

Although generally limited to sanitary sewers, many municipalities now include storm water within this by-law. It generally requires all storm water

to be discharged to an approved outlet and regulates the constituents of the discharged water.

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

such devices

Standing water by-law

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 per a determined period of time (e.g. 48 hours)

May be interpreted as prohibitive for soakaways subsurface storage facilities, bioretention, and bioswales

Boulevard planting by-laws

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

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

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

Regulates the collection and allowable discharge location of roof drainage

  • May specify outlet distance from building foundation
  • 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





Field Reconnaissance


  • Neighbourhood characteristics
  • 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 condtion of gardens
    • Distribution and coverage of natural vegetation
    • Location of septic systems
    • Location and style off fencing
    • Prevalence of irrigation systems
    • roadside swales
    • % cur
  • Drainage characteristics
  • Rooftop / drainage characteristics
  • Best management practices info
  • Recommended actions