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==Schools==
==Schools==
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 at your school.
Targeting hard surfaces
Parking areas represent the most significant source of
pollutant loading from school sites and contribute significantly
to increased runoff rates in comparison to natural conditions.
Parking lots of all sizes can be targeted for permeable
pavement retrofits. As an added benefit, permeable pavement
systems have a longer lifespan compared to conventional
asphalt.
High schools often have large parking lots where the capacity
outweighs the demand. These areas represent opportunities
to install bioswales or bioretention 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 drainage
patterns and catch basin 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 granular reservoir to provide storage and
allow infiltration into native soils. Infiltration chambers under
conventional asphalt 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 bioswales or bioretention 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 runoff that is drained internally via rain leaders.
Schools also consume large quantities of water for flushing
toilets and urinals. Rainwater harvesting systems can tackle
both of these issues by intercepting this rooftop runoff and
re-using it for toilet flushing as well as outdoor irrigation. This
option has the benefit providing an ongoing financial benefit
through reduced water bills.
Roof runoff can also be directed to soakaways located on
passive use areas around the building. As this runoff comes
into contact with fewer hard surfaces, it produces better
quality runoff than roads and does not require pretreatment
devices.
Green roof 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
LID 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 runoff on your existing property can
make funds available through:
• Contributions to capital projects like parking lot
rehabilitations which include rain gardens, permeable
pavements, or subsurface infiltration facilities
• Ongoing revenues from long-term land leases to
accommodate surface or subsurface LID 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 LID retrofits can
reduce taxes or prevent costly upgrades required at a later
date.
Table 5.3.1 identifies the LID practices that are common,
possible and unlikely options for the source areas that you
are likely to find on your retrofit 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 LID retrofit projects The scale
of your LID retrofit project will largely determine how you will
proceed with the retrofit process. You can usually complete
small-scale LID 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 LID practices during the summer
break. Include summer operations staff time in
your budget during the planning process.
Small-scale projects
Starting with small-scale projects is a good strategy to
increase interest within your school, determine what support
is available from stakeholder 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 LID 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 LID 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 LID retrofits
include:
• Bioretention
• Enhanced grass swales
• Bioswales
• Perforated pipe systems
• Permeable pavement
• Soakaways
• Infiltration chambers
• Rainwater harvesting (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 bioswale.
Before starting a large-scale retrofit project, consider the
following distinctions that set these retrofits apart from smallscale
projects.
Integration with long-term infrastructure
replacement and rehabilitation plans
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.
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 LID retrofits into
these projects and share construction material, construction
equipment, staff resources, and time.
For example, installing bioretention, infiltration chambers,
or permeable pavement 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 LID retrofits.
Contractors should be pre-qualified based on previous
experience with similar LID 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 LID 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 stakeholder 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, 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. 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 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.
Chapters 3, 4 and 6 provide similar guidance aimed at parks,
municipal facilities, and places of worship. Reading these
chapters may give you additional ideas for implementing LID
on your site.
For further guidance on implementing and constructing LID
practices, please refer to Chapters 7-9. These chapters
provides the next steps for you to implement your LID project,
including building the project team, creating a design,
getting approvals, construction, certification and guidance on
operations and maintenance of LID practices.
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