LID opportunities on public land

From LID SWM Planning and Design Guide
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Small- and large-scale projects

The scale of your LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. project will largely determine how to proceed. While you can usually complete small-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects with in-house expertise and resources, large-scale projects require external support from consultants and contractors.

Small-scale projects

A no-mow zone is a landscape alternative that does not require construction activities. (Source: Aquafor Beech)

Starting with small-scale projects is a good strategy to increase public interest in LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices, gauge municipal support, and gain retrofit experience. Small-scale projects include retrofitting your site with landscape alternatives, rain barrels, enhancements of existing swalesA 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., or using pollution prevention strategies and practices. Small-scale projects require fewer resources and a smaller project budget:

  • They do not require integration into capital works projects
  • Engineering consultants are not required
  • Contractors may not be not required
  • External approvals are not required
  • Consultation with the public is limited

Due to less financial commitment, it can be easier to build colleague support and to gain supervisor approval for small-scale projects. However, small-scale projects like landscape alternatives and pollution prevention may not be easily identified as LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices by the public. Your project team should consider establishing educational signage to inform the public.

Large-scale projects

When installing new parks equipment, consider whether the LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices can be integrated into the design. Here a bioswaleLinear 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 underlying native soil. has been built into the landscape between a playground and sidewalk. (Source: CVCCredit Valley Conservation)

Large-scale projects require significantly more effort, budget and staff than small-scale projects. Large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices include:

Consider a large-scale project if your municipality, school or place of worship would like to be a leader in sustainability. Large-scale projects are often highly visible and attract more public attention. Large-scale projects may also be the only solution to site-specific challenges. For example, if the parking lot on your site does not have existing stormwater controls, small-scale projects are not likely to fully achieve compliance with water quality and quantity objectives. Consider using an infiltration chamber or bioswaleLinear 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 underlying native soil. project to meet those objectives. Before starting a large-scale retrofit project, consider the following distinctions that set these retrofits apart from small-scale projects.

Integration with capital works programs

Most large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits must function with existing site infrastructure, such as storm sewers, catch basinsGround depression acting as a flow control and water treatment structure, that is normally dry., and pavement systems. The construction of large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices often requires these systems to be removed, exposed, or replaced. The best time for this type of project to occur is when an infrastructure replacement or rehabilitation project is already planned.

When LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits are worked into other construction projects, such as parking lot repaving, or grading or drainage improvements, there can be substantial cost savings. Whether big or small, every municipality, school and place of worship spends relatively large sums of money and substantial time planning for major capital projects. This includes redevelopment of public buildings and spaces. Many communities which have undertaken retrofits recognize that even if a relatively small portion of the project funds goes towards LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits, they can retrofit large imperviousA hard surface area (e.g., road, parking area or rooftop) that prevents or retards the infiltration of water into the soil. surfaces and avoid new stormwater management infrastructure projects.

Municipal facility rehabilitation is typically forecast well in advance of the project. Parking lot paving is typically worked into municipal budgets based on expected life cycle and observed wear. As such, funds may be set aside prior to the project planning phases. Long-term forecast budgets may also be available for site revitalization or expansion. These budget forecasts provide opportunities to compare the capital and life-cycle costs and benefits of conventional construction projects against LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits.

Regulatory compliance

The objectives, technologies and standard practices associated with stormwater management are constantly evolving. It is unlikely that the stormwater management practices on your site meet modern industry standards. When you are making changes to your site, it is important to stay ahead of regulation. Your school, park, place of worship or municipal facility may not be required to improve on-site stormwater management infrastructure, but those retrofits can be beneficial and save money and time over the long term. Consider both current and future water regulations which may affect your property. Consulting with your municipality will help you determine if LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits can reduce taxes or prevent costly upgrades required at a later date.

Involvement of consultants and contractors

Consultants are required for large-scale retrofit projects, specifically for the final screening of options, pre-design, detailed design, tender and contract documents, construction supervision and administration, and assumption and verification. Site contractors are also required for large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits.

Ideally, contractors should be pre-qualified based on previous experience with similar LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects.

Intensive public consultation

Stakeholders must be closely involved in the retrofit process for large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects. These projects have longer construction windows, may have significant impacts on long term public use patterns of the site and will have significantly higher costs. Gaining public insight before LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. implementation can help address public concerns and information gaps, as well as identify public supporters and champions. Public consultation can help designers tailor the project to address community concerns, values and use-patterns.

External approvals

Large-scale retrofits may require a variety of approvals at the municipal, watershedThe drainage area of a river.An area of land that drains into a river or a lake. The boundary of a watershed is based on the elevation (natural contours) of a landscape., provincial, and/or federal level. Since LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. is still relatively new, you may encounter policies or bylaws that present barriers to LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit projects. Alternatively, the municipality may have to amend or enforce some policies and bylaws to facilitate the implementation of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects on your site.

Parks

The bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. area installed at O’Connor Park in Mississauga is part of a stormwater management system that treats parking lot 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. prior to discharging to a local wetlandA vegetated area such as a bog, fen, marsh, or swamp, where the soil or root zone is saturated for part of the year.. (Source: CVCCredit Valley Conservation)
Urban parkettes may look small, but they have the potential to treat a large surface area of road. Typical ratios of imperviousA hard surface area (e.g., road, parking area or rooftop) that prevents or retards the infiltration of water into the soil. 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. to a bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. range from 5:1 to 15:1. (Source: CVCCredit Valley Conservation)
The road surface (left) contributes significantly more stormwater pollutants than the parkland area (right). To achieve maximum watershed benefit a designer could consider accepting 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. from this external area. (Source: CVCCredit Valley Conservation)
Source areas within a typical park

Parks range from simple parcels of municipal property to complex outdoor recreational facilities that include parking, sidewalks, trails, sports fields, field houses, operations facilities and washrooms. Each distinct area of your site can be a source for 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. (referred to as a ‘source areaThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale.’). Target these areas when introducing LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. in your park.

Targeting hard surfaces

Hard surfaces like parking lots and internal driveways are the most obvious targets for both stormwater quality and water balanceThe accounting of inflow and outflow of water in a system according to the components of the hydrologic cycle. improvements. These features produce more 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. than any other area on your site. 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. from parking lots and driveways is typically more polluted than other source areas. Common water quality concerns include sandMineral particles which are smaller than 2 mm, and which are free of appreciable quantities of clay and silt. Coarse sand usually designates sand grains with particle size between 0.2 and 0.02 mm. and salt from winter de-icing operations, hydrocarbons (gasoline) and heavy metals from vehicle breakdowns.

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. from vegetated areas of parks will be relatively clean and more closely matches the natural water balanceThe accounting of inflow and outflow of water in a system according to the components of the hydrologic cycle.. On municipal park properties, hard surfaces are usually located adjacent to pervious areas such as lawns, gardens or naturalized areas. This makes parks an ideal location for a LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit. Where grading allows, you can construct bioswales and bioretention areas in these green areas to pre-treat water prior to infiltrationThe slow movement of water into or through a soil or drainage system.Penetration of water through the ground surface..

You can also design parking surfaces and internal roadways as infiltration systems using permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil.. This retrofit strategy can be combined with other LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices. Pathways paved with permeable paving are another LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. option for your park. They reduce 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. volumes and encourage on-site infiltrationThe slow movement of water into or through a soil or drainage system.Penetration of water through the ground surface.. Exfiltration trenches are a viable option on many parks sites as well, as they provide an alternative to conventional conveyance systems (such as storm sewers). They encourage infiltration from hard surfaces and can be used to convey water to other LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. features.

Accepting drainage from off-site areas

Does municipally owned land drain into your retrofit site? If so, this is an opportunity to provide stormwater controls for these areas. Roads are the most common source of 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. from external properties into parks. Treating municipal road 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. in a park requires planning input from municipal roads department staff. For these projects, the team must understand how all road activities, including winter maintenance and potential roadwork, will affect the operation of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices in the park.

Inter-municipal transfer of funds

Integrating LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices into the municipal stormwater management framework may require a change in how municipal funds are managed. Traditional stormwater management maintenance resources and funds may have to be transferred to a more landscape-based stormwater management maintenance program. Instead of infrequent but expensive stormwater management pondA body of water smaller than a lake, often artificially formed. sedimentSoil, sand and minerals washed from land into water, usually after rain. They pile up in reservoirs, rivers and harbors, destroying fish-nesting areas and holes of water animals and cloud the water so that needed sunlight might not reach aquatic plans. Careless farming, mining and building activities will expose sediment materials, allowing them to be washed off the land after rainfalls. removal operations, time and resources would be spent on more frequent but inexpensive maintenance projects, including pruning and weeding bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. practices or sweeping permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil.. Municipalities generally have the required staff and infrastructure within departments (e.g. arborists and horticulturalists in parks departments) to manage the maintenance of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. measures. However, funding this maintenance may require a transfer of funding and additional training. The federal Gas Tax Fund (GTF) is another funding option for LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits. This federal transfer provides long-term funding for municipalities to build and revitalize public infrastructure. Up to 30% of a municipality's yearly GTF allotment can be used for stormwater management.

Source Areas

The best LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. option for your site will depend what types of source areas are present. Source areas may include:

  • Active use areas
  • Passive use areas
  • Pedestrian walkways
  • Internal driveways
  • Parking lots

On park sites, pollution prevention is often associated with changes to operations and maintenance practices and has not been included in the table below. Options and implementation strategies for a few of these source areas will give you some ideas for your park site.

LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. opportunities in parks
(** = Common, * = Possible, o = Unusual)
Source areaThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale. Permeable paving Bioretention Enhanced grass swales Bioswales Infiltration trenches and chambers Exfiltration trenches Landscape alternatives Prefabricated modules
Active use area ** o * * ** * o o
Passive use area o ** ** ** ** ** ** **
Pedestrian walkway ** ** ** ** ** * * o
Internal driveway ** ** ** ** ** ** o *
Parking lot ** ** ** ** ** ** o **

Making it happen: Approaches to getting LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. into parks

The scale of your LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. project will largely determine how to proceed. While you can usually complete small-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects with in-house expertise and resources, large-scale projects require external support from consultants and contractors.

Small-scale projects

A no-mow zone is a landscape alternative that does not require construction activities. (Source: Aquafor Beech)

Starting with small-scale projects is a good strategy to increase public interest in LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices, gauge municipal support and gain experience. Small-scale projects include retrofitting your park with landscape alternatives, rain barrels, or by using pollution prevention strategies and practices.

Small-scale projects require fewer resources and a smaller project budget:

  • They do not require integration into capital works projects
  • Engineering consultants are not required
  • Contractors may not be not required
  • External approvals are not required
  • Consultation with the public is limited

Due to less financial commitment, it can be easier to build colleague support and to gain supervisor approval for small-scale projects. However, small-scale projects like landscape alternatives and pollution prevention may not be easily identified as LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices by the public. Your project team should consider establishing educational signage to inform the public.

Large-scale projects

When installing new parks equipment, consider whether the LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices can be integrated into the design. Here a bioswaleLinear 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 underlying native soil. has been built into the landscape between a playground and sidewalk. (Source: CVCCredit Valley Conservation)

Large-scale projects require significantly more effort, budget, and staff than small-scale projects. Large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices include:

Consider a large-scale project if your municipality or department would like to be a leader in sustainability. Large scale projects are often highly visible and attract more public attention. Large-scale projects may also be the only solution to site-specific challenges. For example, if the parking lot on your site does not have existing stormwater controls, small-scale projects are not likely to fully achieve compliance with water quality and quantity objectives. Consider using an infiltration chamber or bioswaleLinear 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 underlying native soil. project to meet those objectives.

Before starting a large-scale retrofit project, consider the following distinctions that set these retrofits apart from small-scale projects.

Integration with capital works programs

Most large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits must function with existing site infrastructure, such as storm sewers, catch basinsGround depression acting as a flow control and water treatment structure, that is normally dry. and pavement systems. Constructing large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices often requires these systems to be removed, exposed or replaced. Planned infrastructure replacement or rehabilitation projects provide opportunities for implementing LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices. For example, if a planned project requires removing existing pavement, infiltration chambers, permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil. or bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. can be incorporated. Budget and resources already set aside for infrastructure projects can be set aside for a retrofit project including replacement existing infrastructure.

Involvement of consultants and contractors

Consultants are required for large-scale retrofit projects, specifically for the final screening of options, pre-design, detailed design, tender and contract documents, construction supervision and administration, and assumption and verification. Site contractors are also required for large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits.

Ideally, contractors should be pre-qualified based on previous experience with similar LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects.

More intensive public consultation

Stakeholders must be closely involved in the retrofit process for large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects. These projects have longer construction windows, may have significant impacts on long term public use patterns of the park, and will have significantly higher costs. Gaining public insight in advance of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. implementation can help address public concerns and information gaps, as well as identify public supporters and champions. Public consultation can help designers tailor the project to address community concerns and values.

External approvals

Large-scale park retrofits may require a variety of approvals at the municipal, watershedThe drainage area of a river.An area of land that drains into a river or a lake. The boundary of a watershed is based on the elevation (natural contours) of a landscape., provincial and/or federal level. Since LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. is still relatively new, you may encounter policies or bylaws that present barriers to LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit projects. Alternatively, the municipality may have to enforce some policies and bylaws to facilitate the implementation of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects within parks.

Municipal facilities

Each distinct area of your site can be a source for 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. (referred to as a ‘source areaThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale.’). Target these areas when introducing LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. in your municipal facility.

Targeting hard surfaces

Municipal facilities have large parking lots to accommodate public demand. Parking areas represent the most significant source of pollutant loadingThe total mass of a pollutant entering a waterbody over a defined time period.The net amount of something (e.g. chemical, such as phosphorus), calculated as the product of concentration and volume in a given time. Some BMPs significantly reduce loading of pollutants to the environment by reducing volume more so than concentration. from these sites and contribute significantly to increased 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. rates in comparison to natural conditions. Parking lots include areas for parking, areas for driving, and islands or landscape planters used for calming traffic, directing vehicles and improving pedestrian safety.

LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices can be incorporated into all areas of a parking lot. You can use bioretention in parking lot islands and along the lot perimeter. Standard curbs with small cut-outs (called ‘curb cuts’) can allow water to easily enter biorentention practices while also preventing damage from cars.

Bioswales are excellent options in parking lot islands or along lot perimeters. Parking lots with existing perimeter ditching are ideal for bioswaleLinear 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 underlying native soil. integration due to their extended continuous flow path.

Prefabricated modular infiltration chambers are gaining acceptance for their easy integration with parking lot functions. These subsurface systems are typically installed over a coarse granularGravel, 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. reservoir to provide storage and allow infiltration into native soils. Infiltration chambers under conventional asphaltA mixture of mineral aggregates bound with bituminous materials, used in the construction and maintenance of paved surfaces. system work well on sites where parking demand and other site uses do not allow space for a stormwater feature.

Stormwater planters beautify this building entrance. The entrance receives a lot of traffic during business hours, making it an ideal location for a high visibility LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practice. (Source: Aquafor Beech)

Permeable pavements are also an option in large municipal parking lots. Pervious concrete, permeable interlocking concrete pavers, and porous asphaltA mixture of mineral aggregates bound with bituminous materials, used in the construction and maintenance of paved surfaces. can detain stormwater and increase infiltrationThe slow movement of water into or through a soil or drainage system.Penetration of water through the ground surface..

Municipal facilities provide excellent opportunities for integrating rainwater harvesting systems. Rainwater harvestingThe practice of intercepting, conveying and storing rainwater for future use. Captured rainwater is typically used for outdoor non-potable water uses such as irrigation, or in the building to flush toilets. systems have two requirements: an area for catchmentThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale. of relatively clean 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. and a nearby demand for water usage. Municipal facilities often have large rooftop areas producing relatively clean 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.. Installing a cisternTank used to store rainwater (typically roof runoff) for later use. internal to the building or buried adjacent to the building can provide a sustainable source of water for site irrigationHuman application of water to agricultural or recreational land for watering purposes. City of Toronto Wet Weather Flow Management November 2006 47 needs for landscaped areas, recreational fields and indoor use (e.g. flushing toilets and urinals).

Targeting highly visible areas

If your LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. integration strategy involves highly visible LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices, consider targeting areas with high-volume pedestrian traffic. This can help promote LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting.'s visibility among the public and increase support for future LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects.

Targeting pollution prevention opportunities

On some municipal sites, pollution prevention techniques and strategies are the best approaches to mitigating the environmental impact of your site. Retrofits of municipal works yards require a different approach than other land uses discussed in this guide. Works yards do not offer substantial opportunities for public interaction. LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits should focus primarily on reducing pollution generated on-site. Fueling stations, waste storage areas, truck washing stations, sandMineral particles which are smaller than 2 mm, and which are free of appreciable quantities of clay and silt. Coarse sand usually designates sand grains with particle size between 0.2 and 0.02 mm. and salt storage, staging areas and water conveyance features are ideal for pollution prevention.

Source areas

The best LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. option for your site will depend what source areas are present. Types of source areas include:

Source areas within a typical community centre.
  • Active use areas
  • Passive use areas
  • Pedestrian walkways
  • Internal driveways
  • Parking lots

On municipal sites, pollution prevention is often associated with changes to operations and maintenance practices and has not been included in the table below.

LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. opportunities in municipal buildings
(** = Common, * = Possible, o = Unusual)
Source areaThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale. Permeable pavements Bioretention Enhanced grass swales / bioswales Green roofs Soakaways and infiltration chambers Perforated pipe systems Rainwater harvesting Landscape alternatives Prefabricated modules Pollution prevention
Active use area ** ** ** o ** * o * o **
Passive use area o ** * o ** ** o ** ** **
Pedestrian walkway ** ** ** o ** * o * * **
Internal driveway ** ** ** o ** ** o o ** **
Parking lot ** ** ** o ** ** o o ** **
Building * * * ** ** * ** o o **

Schools

The Peel District School Board's Adult Education Centre South school partnered with the City of Mississauga to manage 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. from the adjacent street, Elm Drive, on their property. This partnership benefits the City by giving it space to provide an enhanced level of stormwater treatment, and benefited the school through the construction of new parking lay-bys for students. The site is maintained by the City of Mississauga. Source: CVCCredit Valley Conservation

Each distinct area of your site can be a source for 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. (referred to as a ‘source areaThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale.’). These areas should be targeted when introducing LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. at your school.

Targeting hard surfaces

Parking areas represent the most significant source of pollutant loadingThe total mass of a pollutant entering a waterbody over a defined time period.The net amount of something (e.g. chemical, such as phosphorus), calculated as the product of concentration and volume in a given time. Some BMPs significantly reduce loading of pollutants to the environment by reducing volume more so than concentration. from school sites and contribute significantly to increased 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. rates in comparison to natural conditions. Parking lots of all sizes can be targeted for permeableThe property of a material that allows the infiltration or passage of water (or other liquids). pavement retrofits. As an added benefit, permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil. systems have a longer lifespan compared to conventional asphaltA mixture of mineral aggregates bound with bituminous materials, used in the construction and maintenance of paved surfaces.. High schools often have large parking lots where the capacity outweighs the demand. These areas represent opportunities to install bioswalesLinear 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 underlying native soil. or bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. areas in parking lot islands. Standard curbs with small cut-outs (called ‘curb cuts’) can allow water to easily enter biorentention practices while also preventing damage from cars. Often the existing drainageNatural or artificial means of intercepting and removing surface or subsurface water (usually by gravity). patterns and catch basinGround depression acting as a flow control and water treatment structure, that is normally dry. locations can be preserved and integrated into the design. These practices will also function to improve pedestrian safety and calm traffic. Other types of infiltrating practices like infiltration chambers are gaining acceptance for their easy integration with parking lot functions. These subsurface systems are typically installed over a coarse granularGravel, 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. reservoir to provide storage and allow infiltration into native soils. Infiltration chambers under conventional asphaltA mixture of mineral aggregates bound with bituminous materials, used in the construction and maintenance of paved surfaces. systems work well on sites where parking demand does not allow space for a stormwater feature. Grassed areas adjacent the parking lots are ideal areas to implement bioswalesLinear 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 underlying native soil. or bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. areas. Perforated pipe systems may also work in areas adjacent to parking lots.

Roof options

Schools typically have large flat roofs that produce a significant amount of 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. that is drained internally via rain leaders. Schools also consume large quantities of water for flushing toilets and urinals. Rainwater harvestingThe practice of intercepting, conveying and storing rainwater for future use. Captured rainwater is typically used for outdoor non-potable water uses such as irrigation, or in the building to flush toilets. systems can tackle both of these issues by intercepting this rooftop 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. and re-using it for toilet flushing as well as outdoor irrigationHuman application of water to agricultural or recreational land for watering purposes. City of Toronto Wet Weather Flow Management November 2006 47. This option has the benefit providing an ongoing financial benefit through reduced water bills. Roof 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. can also be directed to soakaways located on passive use areas around the building. As this 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. comes into contact with fewer hard surfaces, it produces better quality 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. than roads and does not require pretreatmentInitial capturing and removal of unwanted contaminants, such as debris, sediment, leaves and pollutants, from stormwater before reaching a best management practice; Examples include, settling forebays, vegetated filter strips and gravel diaphragms. devices. Green roofA 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. retrofits are another retrofit option for schools. When applying for external funding from organizations, highlight the fact that green roofs reduce energy usage by providing insulation during the winter and evaporative cooling during the summer.

Pollution prevention (P2)

On school sites, P2 strategies and practices, such as modifying de-icing programs and isolating drainage from waste storage areas, can be applied to operations and maintenance activities. Discuss these changes with your school board and operations staff.

School board partnerships with municipalities

LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices located on school grounds can also be used to treat stormwater from external properties. These partnership opportunities give schools the potential to create new revenue. Accepting and treating 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. on your existing property can make funds available through: • Contributions to capital projects like parking lot rehabilitations which include rain gardens, permeableThe property of a material that allows the infiltration or passage of water (or other liquids). pavements, or subsurface infiltration facilities • Ongoing revenues from long-term land leases to accommodate surface or subsurface LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits • Funds for maintenance of on-site LIDs

Regulatory Compliance

The objectives, technologies, and standard practices associated with stormwater management are constantly evolving. It is unlikely that the stormwater management practices on your site meet modern industry standards. When you are making changes to your site, it is important to stay ahead of the regulations. Your school may not be required to improve on-site stormwater management infrastructure, but those retrofits can be beneficial and save money and time over the long term. Consider both current and future water regulations which may affect your property. Consulting with your municipality will help you determine if LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits can reduce taxes or prevent costly upgrades required at a later date. The table below identifies the LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices that are common, possible and unlikely options for the source areas that you are likely to find on your school site. These source areas are: • Active use area • Passive use area • Pedestrian walkway • Internal driveway • Parking lot An aerial photo of a school property with each of these source areas accompanies Table 5.3.1. Options and implementation strategies for a few of these source areas will give you some ideas for your site. This guide provides two tiers of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit projects The scale of your LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit project will largely determine how you will proceed with the retrofit process. You can usually complete small-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects with in-school expertise and resources. Large-scale projects will require external support from consultants and contractors. It is often difficult to ask students or teachers to maintain LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices during the summer break. Include summer operations staff time in your budget during the planning process.

Small-scale projects

A student helps with planting at Fletchers Creek Senior School. Small-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects are a great way to engage with young children. Source: CVCCredit Valley Conservation

Starting with small-scale projects is a good strategy to increase interest within your school, determine what support is available from stakeholderAny person, agency or group who has a direct interest in the purpose of a proposed undertaking. groups (parent council, school board, administration and operations) and gain retrofit experience. Small-scale projects include retrofitting your school property with landscape alternatives or rain barrels, or using pollution prevention strategies and practices. Small-scale projects require fewer resources and require a smaller project budget because: • They do not require integration into long-term infrastructure replacement and rehabilitation plans • Engineering consultants are not required • Contractors may not be required • External approvals are not required • Consultation with the public is limited Due to the smaller financial commitment, it can be easier to build colleague and school board support for small-scale projects. A successful small-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit project on your school property can be a good indication that you are ready to take on a more intensive retrofit project. You now know the resources that are available and understand the internal municipal processes required to move a LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. project from planning to finished product.

Large-scale projects

Large-scale projects require significantly more effort, budget, and staff than small-scale projects. Large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits include:

  • BioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation.
  • Enhanced grass swalesA 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.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.
  • BioswalesLinear 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 underlying native soil.
  • Perforated pipe systems
  • Permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil.
  • Soakaways
  • Infiltration chambers
  • Rainwater harvestingThe practice of intercepting, conveying and storing rainwater for future use. Captured rainwater is typically used for outdoor non-potable water uses such as irrigation, or in the building to flush toilets. (excluding rain barrels)
  • Prefabricated modules
  • Green roofs

Consider a large-scale project if your school board is striving to be a leader in sustainability. Large-scale projects are often highly visible and attract more public attention. They may also be the only solution to site-specific challenges. For example, if the parking lot of your site does not have existing stormwater controls, small-scale projects are unlikely to fully achieve compliance with water quality and water quantity objectives. Instead, use a large-scale project like an infiltration chamber or bioswaleLinear 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 underlying native soil.. Before starting a large-scale retrofit project, consider the following distinctions that set these retrofits apart from small-scale projects.

Source areas within a typical school site.

Integration with long-term infrastructure replacement and rehabilitation plans

Most large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits must function with existing site infrastructure, such as storm sewers, catch basinsGround depression acting as a flow control and water treatment structure, that is normally dry., and pavement systems. The construction of large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices often requires these systems to be removed, exposed, or replaced. The best time for this type of project to occur is when an infrastructure replacement or rehabilitation project is already planned. Like other large public sites, schools typically have maintenance programs that take into consideration the expected life cycle of critical site components, including parking lots and roofs. To save construction costs, incorporate LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits into these projects and share construction material, construction equipment, staff resources, and time. For example, installing bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation., infiltration chambers, or permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil. in a parking lot will require the existing pavement to be removed. Budget and resources that have been set aside for a parking lot replacement could be transferred to a retrofit project.

Involvement of consultants and contractors

Consultants are required for large-scale retrofit projects, specifically for the final screening of options, pre-design, detailed design, tender and contract documents, construction supervision and administration, and assumption and verification. The consultant selection process is described in Chapter 7. Site contractors are also required for large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits. Contractors should be pre-qualified based on previous experience with similar LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects. Remember, the contractor with the lowest bid does not necessarily deliver the best product. Refer to Chapter 7 for tips on how to select the right contractor for your project.

More intensive public consultation

Stakeholders must be closely involved in the retrofit process for large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects. These projects have longer construction windows, larger costs, and will more significantly affect the use patterns of the property. Large-scale projects are also more complex systems that require continued inspections, operations, and maintenance to achieve continued success. All stakeholderAny person, agency or group who has a direct interest in the purpose of a proposed undertaking. groups must be aware of the long-term project needs before implementation.

External approvals

Large-scale retrofits may require a variety of approvals at the municipal, watershedThe drainage area of a river.An area of land that drains into a river or a lake. The boundary of a watershed is based on the elevation (natural contours) of a landscape., provincial, and/or federal level. Since LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. is still relatively new, you may encounter policies or bylaws that present barriers to LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit projects. Conduct a review of relevant municipal and school board policies prior to implementing a large-scale retrofit. School board policies may require amendments to move forward.

Next Steps

After reading this section you should know how to select the right LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practice for your site. You should also be familiar with the details you need to consider before undertaking an LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit. For further guidance on implementing and constructing LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices, please refer to Chapters 7-9. These chapters provides the next steps for you to implement your LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. project, including building the project team, creating a design, getting approvals, construction, certification and guidance on operations and maintenance of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices.

LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. opportunities at schools
(** = Common, * = Possible, o = Unusual)
Source areaThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale. Permeable pavement Bioretention Enhanced grass swales / bioswales Green roofs Soakaways and infiltration trenches Perforated pipe systems Rainwater harvesting Landscape alternatives Prefabricated modules Pollution prevention
Active use area ** ** ** o ** * o * o **
Passive use area o ** * o ** ** o ** ** **
Pedestrian walkway ** ** ** o ** * o * o **
Internal driveway ** ** ** o ** ** o o * **
Parking lot ** ** ** o ** ** o o ** **
Building * * * ** ** * ** o o **

Places of worship

Source areas within a typical place of worship

Each distinct area of your site can be a source for 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. (referred to as a ‘source areaThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale.’). One or more of these areas should be targeted when introducing LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. at your place of worship.

Targeting hard surfaces

Hard surfaces such as parking lots are a great opportunity to implement LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting.. Parking lots are the main source of 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. and represent the most significant source of stormwater pollutants coming from your site. Parking lots at places of worship are typically busy only on select days of the week when groups gather for prayer or other community activities. Due to this intermittent schedule, parking lots at these facilities are often rented for other purposes during times of low usage. On sites where peak demand does not approach the total capacity of the lot, consider reducing the parking surface. Retrofit options for these large parking lot areas include permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil., bioswalesLinear 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 underlying native soil. and bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. areas. A benefit of permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil. systems is that they often have a longer lifespan than conventional infrastructure. The freeze-thaw cycle of the Ontario climate is tough on pavement. Frost heaving and slumping can cause cracks and potholes because of the expansion and contraction of water. The expected lifespan for conventional asphaltA mixture of mineral aggregates bound with bituminous materials, used in the construction and maintenance of paved surfaces. pavement in a northern climate, such as Ontario, is approximately 15 to 20 years. A well-maintained porous asphaltA mixture of mineral aggregates bound with bituminous materials, used in the construction and maintenance of paved surfaces. system can last for over 30 years, and permeable interlocking concrete pavers can have a design life of 20 to 25 years or greater. Using LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. techniques to manage stormwater can also eliminate or reduce the need for an on-site storm sewer system. By eliminating piping, failure points in the pavement, such as areas around catch basinsGround depression acting as a flow control and water treatment structure, that is normally dry. and manholes, can be eliminated. A design that does not use storm sewers also negates the need to replace on-site piping, thereby saving long-term infrastructure replacement costs. Prefabricated modular infiltration chambers are gaining acceptance because they are easy to integrate with parking lot functions. These subsurface systems are typically installed over a coarse granularGravel, 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. reservoir to provide water storage and allow infiltration into native soils. Infiltration chambers under conventional asphaltA mixture of mineral aggregates bound with bituminous materials, used in the construction and maintenance of paved surfaces. systems work well on sites where parking demand does not allow space for a stormwater feature.

Landscaped areas

Landscaped or lawn areas adjacent to the parking lot or building present opportunities for implementation of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices such as bioswalesLinear 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 underlying native soil. and bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. areas. These areas typically accept 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. from nearby hard surfaces and provide water quality and water balanceThe accounting of inflow and outflow of water in a system according to the components of the hydrologic cycle. benefits.

Roof options

Rainwater harvestingThe practice of intercepting, conveying and storing rainwater for future use. Captured rainwater is typically used for outdoor non-potable water uses such as irrigation, or in the building to flush toilets. systems can be simple or complex depending on the architecture and roof drainage patterns of your building. Many places of worship have peaked roofs with piping to convey water from the rooftop. If your site is set up this way, it can be easy to integrate harvesting systems into the landscape surrounding your building. Roof 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. can also be directed to soakaways located on passive use areas around your building. Due to the relatively good quality of this 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., pre-treatment devices are not required.

Source Areas

The LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. option that best fits your site will depend what types of source areas are present. Types of source areas include:

  • Active use area
  • Passive use area
  • Pedestrian walkway
  • Internal driveway
  • Parking lot

On park sites, pollution prevention is often associated with changes to operations and maintenance practices and has not been included in Table 6.3.1. An aerial photo of a park with each of these source areas accompanies Table 6.3.1. Options and implementation strategies for a few of these source areas will give you some ideas for your park site.

The scale of your LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit project will largely determine how you will proceed. You can usually complete small-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects with in-house expertise and resources. Large-scale projects will require external support from consultants and contractors.

Small-scale projects

Starting with small-scale projects is a good strategy to increase interest within your community, determine if support is available from stakeholderAny person, agency or group who has a direct interest in the purpose of a proposed undertaking. groups and gain retrofit experience. Small-scale projects include retrofitting your property with landscape alternatives, rain barrels or using pollution prevention strategies and practices.

Small-scale projects require few resources and a small project budget because:

  • They do not require integration into capital works projects
  • Engineering consultants are not required
  • Contractors are not required
  • External approvals are not required
  • Consultation with the public is limited

Due to the less significant financial commitment, it can be easier to build the case for support for small-scale projects. A successful small-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit project on your property is a good indication that you are ready to take on a more intensive retrofit project. You now know the resources that Large-scale projects Large-scale projects require significantly more effort, budget, and staff than small-scale projects. Large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits include:

  • BioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation.
  • Enhanced grass swalesA 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.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.
  • BioswalesLinear 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 underlying native soil.
  • Perforated pipe systems
  • Permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil.
  • Soakaways
  • Infiltration chambers
  • Rainwater harvestingThe practice of intercepting, conveying and storing rainwater for future use. Captured rainwater is typically used for outdoor non-potable water uses such as irrigation, or in the building to flush toilets. (excluding rain barrels)
  • Prefabricated modules
  • Green roofs

Consider a large-scale project if your place of worship is striving to be a community leader in sustainability. Large-scale projects are often highly visible and attract more public attention. They may also be the only solution to site-specific challenges, like poor drainageNatural or artificial means of intercepting and removing surface or subsurface water (usually by gravity).. Before starting a large-scale retrofit project consider the distinctions that set these retrofits apart from small-scale projects.

Integration with long-term infrastructure replacement and rehabilitation plans

Most large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits must function with existing site infrastructure, such as storm sewers, catch basinsGround depression acting as a flow control and water treatment structure, that is normally dry., and pavement systems. The construction of large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. practices often requires these systems to be removed, exposed, or replaced. The best time for this type of project is when an infrastructure replacement or rehabilitation project is already planned. Maintenance programs and budgets that take into consideration the expected life cycle of critical site components, including parking lot and roofs, are valuable resources for large-scale projects. If the replacement of these features is forecasted in your site budget well in advance, asses if it is advantageous to incorporate LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits into these projects. Remember, sharing construction materials, construction equipment, staff resources, and time will reduce the budget for your retrofit. For example, installing bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation., infiltration chambers, or permeable pavementAn alternative practice to traditional impervious pavement, prevents the generation of runoff by allowing precipitation falling on the surface to infiltrate through the surface course into an underlying stone reservoir and, where suitable conditions exist, into the native soil. in a parking lot will require the existing pavement to be removed. Budget and resources that have been set aside for a parking lot replacement could be transferred to the LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit project.

Involvement of consultants and contractors

Consultants are required for large-scale retrofit projects, specifically for the final screening of options, pre-design, detailed design, tender and contract documents, construction supervision and administration, and assumption and verification.

Site contractors are also required for large-scale LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofits. Contractors should be pre-qualified based on previous experience with similar LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects.

External approvals Large-scale retrofits may require a variety of approvals at the municipal, watershedThe drainage area of a river.An area of land that drains into a river or a lake. The boundary of a watershed is based on the elevation (natural contours) of a landscape., provincial, and/or federal level. Since LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. is still relatively new, you may encounter policies or bylaws that present barriers to LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. retrofit projects. Alternatively, the municipality may have to amend or enforce some policies and bylaws to facilitate the implementation of LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. projects on your site.

LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. opportunities at Places of Worship
(** = Common, * = Possible, o = Unusual)
Source areaThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale. Permeable pavement Bioretention Enhanced grass swales / bioswales Green roofs Soakaways and infiltration trenches Perforated pipe systems Rainwater harvesting Landscape alternatives Prefabricated modules Pollution prevention
Active use area ** ** ** o ** * o * o o
Passive use area o ** * o ** ** o ** ** o
Pedestrian walkway ** ** ** o ** * o * o o
Internal driveway ** ** ** o ** ** o o * *
Parking lot ** ** ** o ** ** o o ** *
Building * * * ** ** * ** o o *

stuff to maybe integrate into the above

Figure 6.3.1: When considering any parking lot retrofit, first determine if the parking spaces provided are consistent with the demand. In place of worship, the demand will fluctuate. (Source: CVCCredit Valley Conservation)

Did you know that green roofs can help reduce your heating and cooling costs? These systems absorb heat and act as insulators for buildings. It has been estimated that a 3,000 m2 green roofA 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. on a one story building in Toronto could reduce the cost of cooling a building in the summer by 6% and the cost of heating a building by 10% in the winter23.