Difference between revisions of "LID opportunities in park lands"
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The LID option that best fits your site will depend what types | The LID option that best fits your site will depend what types | ||
of source areas are present. Types of source areas include: | 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 | On park sites, pollution prevention is often associated with | ||
changes to operations and maintenance practices and has | changes to operations and maintenance practices and has | ||
Line 133: | Line 133: | ||
and staff than small-scale projects. Large-scale LID projects | and staff than small-scale projects. Large-scale LID projects | ||
include: | include: | ||
*Bioretention | * Bioretention | ||
* Enhanced grass swales | * Enhanced grass swales | ||
* Bioswales | * Bioswales | ||
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quality and quantity objectives. Consider using an infiltration | quality and quantity objectives. Consider using an infiltration | ||
chamber or bioswale project to meet those objectives. | chamber or bioswale project to meet those objectives. | ||
Before starting a large-scale retrofit project, consider the | Before starting a large-scale retrofit project, consider the | ||
following distinctions that set these retrofits apart from | following distinctions that set these retrofits apart from small-scale projects.<br> | ||
projects.<br> | |||
'''<h4>Integration with capital works programs</h4>''' | '''<h4>Integration with capital works programs</h4>''' | ||
Most large-scale LID retrofits must function with existing | Most large-scale LID retrofits must function with existing |
Revision as of 19:05, 5 October 2017
LID opportunities in parks
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 runoff (referred to as a ‘source area’). These
areas should be targeted when introducing LID in your park.
Targeting hard surfaces
Hard surfaces like parking lots and internal driveways are the
most obvious areas to target for both stormwater quality and
water balance improvements. These features produce more
runoff than any other area on your site. Water quality of runoff
from parking lots and driveways is typically more polluted
than other source areas. Common water quality concerns
include sand and salt from winter de-icing operations, and
hydrocarbons (gasoline) and metals from vehicle breakdowns
Runoff from vegetated areas of parks will be relatively
clean and more closely match the natural water balance.
On municipal park properties, hard surfaces are usually
located adjacent to pervious areas such as lawns, gardens or naturalized areas. This makes an ideal location for a LID
retrofit. Where grading allows, you can construct bioswales
and bioretention areas in these green areas to pre-treat water
prior to infiltration.
You can also design parking surfaces and internal roadways
as infiltration systems using permeable pavement. This retrofit
strategy can be combined with other LID practices.
A pedestrian pathway paved with permeable pavement
is another LID option for your park. They will reduce runoff
volumes and encourage on-site infiltration. Pervious pipes
are a viable option on many parks sites as well. They can be
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 LID 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 runoff from external
properties into parks. Treating municipal road runoff in a park
requires planning input from municipal roads department
staff. For these projects, the team must understand how all
roads activities, including winter maintenance and potential
roadwork, will affect the operation of LID practices in the park.
Inter-municipal transfer of funds
Integrating LID practices into the municipal stormwater management framework may change 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 pond sediment removal operations, time and resources will be spent on more frequent but inexpensive maintenance projects including pruning and weeding bioretention practices or sweeping permeable pavement.
Municipalities generally have the required staff and infrastructure within departments (e.g. arborist and horticulturalists in parks departments) to manage the maintenance of LID 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
funding LID retrofits. This is a federal transfer that provides
long term funding for municipalities to build and revitalize
public infrastructure. Up to 30% of municipalities yearly GTF
allotment can be used towards stormwater management.
Source Areas
The LID 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 3.3.1. An aerial photo of a park with each of these source areas accompanies Table 3.3.1. Options and implementation strategies for a few of these source areas will give you some ideas for your park site.
LID Options for Parks | ||||||||
Source area | Permeable pavement | Bioretention | Enhanced grassed swales | Bioswales | Soakaways and infiltration chambers | Perforated pipe system | Landscape alternatives | Prefabricated modules |
Active use area | ** | o | * | * | ** | * | o | o |
Passive use area | o | ** | ** | ** | ** | ** | ** | ** |
Pedestrian walkway | ** | ** | ** | ** | ** | * | * | o |
Internal driveway | ** | ** | ** | ** | ** | ** | o | * |
Parking lot | ** | ** | ** | ** | ** | ** | o | ** |
** Common option | * Possible option | o Unlikely |
---|
Making it happen: Approaches to getting LID into parks
The scale of your LID project will largely determine how you will proceed. This guide provides two tiers of LID park retrofit projects. You can usually complete small-scale LID 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 public interest in LID practices, gauge municipal
support, and gain experience. Small-scale projects include
retrofitting your parks site 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 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 the less significant financial commitment, it can be
easier to build colleague and supervisor support for small-scale
projects.
Small-scale projects like landscape alternatives and pollution
prevention may not be easily identified as LID practices by
the public. Your project team should consider establishing
educational signage to inform the public.
Large-scale projects
Large-scale projects require significantly more effort, budget, and staff than small-scale projects. Large-scale LID projects include:
- Bioretention
- Enhanced grass swales
- Bioswales
- Perforated pipe systems
- Permeable pavement
- Soakaways
- Infiltration chambers
- Rainwater harvesting (excluding rain barrels)
- Prefabricated modules
Consider a large-scale project if your municipality or department would like to be a leader in sustainability. Largescale 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 bioswale 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 LID retrofits must function with existing
site infrastructure, such as storm sewers, catch basins,
and pavement systems. The construction of large-scale
LID 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.
For example, installing bioretention, infiltration chambers,
or permeable pavement in a parking lot requires removal of
existing pavement. Budget and resources set aside for parking lot replacement could be transferred to a retrofit project that
includes replacement of this 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 LID retrofits.
Ideally, contractors should be pre-qualified based on previous
experience with similar LID projects.
More intensive public consultation
Stakeholders must be closely involved in the retrofit process for large-scale LID projects. These projects have longer construction windows, may have significant impacts on longterm public use patterns of the park, and will cost significantly more taxpayer dollars. Gaining public insight in advance of LID 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, watershed, provincial, and/or federal level. Since LID is still relatively new, you may encounter policies or bylaws that present barriers to LID retrofit projects. Alternatively, the municipality may have to enforce some policies and bylaws to facilitate the implementation of LID projects within parks.
Next Steps
After reading this chapter you should know how to select the right LID practice for your site. You should also be familiar with the details you need to consider before undertaking an LID retrofit.