Changes

{{TOClimit|2}}

{{TOClimit|2}}

== Process for selecting an individual or suite of LID Options ==

== Process for selecting an individual or suite of LID Options ==

This guidance article intends to help reduce the number of LID options in the preliminary phases of design and to alert the designer to LID opportunities unique to the site-type being assessed. When going through the process of screening LID options, it is important to have a larger contextual understanding of [[Integrated water management]], [[Site design strategies]], [[Siting and layout of development]], and [[Link title]].

This guidance article intends to help reduce the number of LID options in the preliminary phases of design and to alert the designer to LID opportunities unique to the site-type being assessed. When going through the process of screening LID options, it is important to have a larger contextual understanding of [[Integrated water management]], [[Site design strategies]], and [[Siting and layout of development]].

== Site Conditions ==

== Site Conditions ==

The design criteria required to protect, enhance or restore the environmental resources can be grouped under the following five categories:

The design criteria required to protect, enhance or restore the environmental resources can be grouped under the following five categories:

* Flood protection

*[[Flood control]]

* Water quality

*[[Water quality]]

* Erosion control

*Erosion control

* Groundwater recharge

*[[Groundwater|Groundwater recharge]]

* Natural heritage systems or [[green infrastructure]]

*Natural heritage systems or [[green infrastructure]]

== Screen potential LID options ==

== Screen potential LID options ==

===Site constraints===

===Site constraints===

When attempting to apply stormwater BMPs within a development site, give careful consideration to site conditions and constraints. Here is a [[LID Site Criteria and Constraints|handy table]] outlining the factors constraining the use of each LID BMP. Further information regarding constraints to the design of various end-of-pipe BMPs can be found in the Ontario Ministry of the Environment Stormwater Management Planning and Design Manual (2003). Before resorting to end-of-pipe BMPs, evaluate whether LID BMPs can meet the design criteria.

When attempting to apply stormwater BMPs within a development site, give careful consideration to site conditions and constraints. See this [[LID Site Criteria and Constraints|handy table]] for and outline of the factors constraining the use of each LID BMP. Further information regarding constraints to the design of various end-of-pipe BMPs can be found in the Ontario Ministry of the Environment Stormwater Management Planning and Design Manual (2003). Before resorting to end-of-pipe BMPs, evaluate whether LID BMPs can meet the design criteria.

===LID opportunities and land use types===

===LID opportunities and land use types===

When working in retrofit scenarios, note that each particular land-use type - road ROWs, residential, industrial, commercial, institutional, and park lands - all provide unique opportunities and challenges:

When working in retrofit scenarios, note that each particular land-use type - road ROWs, residential, industrial, commercial, institutional, and park lands - all provide unique opportunities and challenges:

*[[LID opportunities and road types]]

*[[LID opportunities in road-right-of-ways]]

*[[LID opportunities in residential types]]

*[[LID opportunities in residential types]]  

*[[LID Opportunities in Industrial & Commercial Types]]

*[[LID opportunities in industrial, commercial and multi-residential types]]

*[[LID opportunities in park lands]]

*[[LID opportunities in public lands]]

===Performance requirements===

===Performance requirements===

Resources for evaluating LID practices within Ontario can be found at [http://www.sustainabletechnologies.ca/wp/home/urban-runoff-green-infrastructure/low-impact-development/ Sustainable Technologies Evaluation Program (STEP)] and [http://www.creditvalleyca.ca/low-impact-development/lid-maintenance-monitoring/lid-monitoring-sites/ Credit Valley Conservation's LID Monitoring program]. For a global perspective on LID performance across various geographical regions, check out the [http://www.bmpdatabase.org/index.htm International Stormwater BMP Database]. Performance data can be downloaded or uploaded and statistical analysis tools are provided.

Resources for evaluating LID practices within Ontario can be found at [http://www.sustainabletechnologies.ca/wp/home/urban-runoff-green-infrastructure/low-impact-development/ Sustainable Technologies Evaluation Program (STEP)] and [http://www.creditvalleyca.ca/low-impact-development/lid-maintenance-monitoring/lid-monitoring-sites/ Credit Valley Conservation's LID Monitoring program]. For a global perspective on LID performance across various geographical regions, check out the [http://www.bmpdatabase.org/index.htm International Stormwater BMP Database]. Performance data can be downloaded or uploaded and statistical analysis tools are provided.

=== Life cycle costing===

=== Life cycle costing===

The capital and life cycle costs of seven Low Impact Development (LID) practices and seventeen design scenarios were evaluated based on a detailed assessment of input costs, maintenance requirements, rehabilitation costs and practice designs relevant to Canadian climates.[http://www.sustainabletechnologies.ca/wp/home/urban-runoff-green-infrastructure/low-impact-development/low-impact-development-life-cycle-costs/ The LID Life Cycle Costing Tool]

After selecting a suite of BMPs and running the models, make a comparison between the modelling results results and the environmental design criteria. Employ an iterative approach, which involves adjusting the size or adding/deleting BMPs until the environmental design criteria are met. The LIDTTT can help with adjusting the size of the features to meet design criteria. Once met, the project can proceed to the detailed design stage.

 

In order to assess if the selected suite of BMPs effectively meet the design criteria either computer models or simple spreadsheet models should be used. Model selection will be based on the size and type of development. A wide range of simple to complex computer models such as Visual OTTHYMO, SWMM, SWMMHYNO, HSP-F andQUALHYMO are available.

 

 

 

 

Once the suite of best management practices have been selected and the models have been run, a comparison of the results and the environmental design criteria can be made. An iterative approach, which involves adjusting the size or adding/deleting BMPs should be used until the environmental design criteria are met. The [http://www.sustainabletechnologies.ca/wp/low-impact-development-treatment-train-tool/ LID Treatment Train Tool] can help with adjusting the size of the features to see if criteria are met. Once met, the project can then proceed to the detailed design stage.