The document discusses a public information centre being held to introduce a study examining basement flooding and surface flooding in Study Area 40. The meeting will present information on the causes of flooding, possible solutions, and next steps in the study process. Attendees are encouraged to provide input. The study aims to identify solutions to reduce flooding risks and improve stormwater quality in the area.

1. View displays and discuss the study with the project staff
Feel free to ask questions and fill out a comment sheet
1
PUBLIC INFORMATION CENTRE #1
September 27, 2016, 6pm – 8pm
Basement Flooding Remediation and Water Quality
Improvement Master Plan Class EA
Study Area 40
WELCOME

2. 2
WELCOMEPURPOSE OF TONIGHT’S MEETING
• Introduce the problem and study objectives
• Present information on the causes of flooding
and the impacts of stormwater runoff
• Present possible alternative solutions and
criteria for evaluating the alternatives
• Outline the next steps in the study process
• Hear from you! Your input is very important.
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

3. 3
WELCOMEPURPOSE OF THIS STUDY
• Examine existing stormwater drainage and
sanitary/combined sewer systems and identify the
causes of basement flooding and/or surface
flooding (severe ponding on streets during
extreme storms).
• Assess control measures to improve the quality of
stormwater runoff as per the City’s Wet Weather
Flow Master Plan.
• Make recommendations to:
• Reduce the risk of future flooding
• Improve the quality of stormwater runoff
before it is discharged to Don River and its
tributaries
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

4. 4
AREAS OF RESPONSIBILITY
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
Watermain
Storm
Lateral
Water
Service
Roof
Downspout
Catch
Basin
Fire
Hydrant
Rear-yard
Catchbasin
Sanitary
Lateral
Storm
Lateral
City’s Responsibility:
Public Lands – Any improvements to the sewer
and storm drainage system to be made within the
City’s property such as parks, roads, and sewer
infrastructure.
Property Owner’s Responsibility:
Private Property Improvements – Each
homeowner is responsible for the operation and
maintenance of drainage systems on private
property which includes:
• Lot grading
• Front and rear-yard or driveway
catchbasins
• Foundation drains
• Sump pumps and backwater valves
• Private tree roots
• What you put down the drains (fats, oils
grease, trash, etc.)
• Disconnecting roof downspouts

5. • The City of Toronto must follow the Municipal Class Environmental
Assessment (EA) process to meet the requirements of Ontario’s EA Act
for all infrastructure projects.
• The EA Act requires the “protection, conservation and wise management
of the environment” while undergoing infrastructure enhancements.
• The EA process is also an opportunity for the public and agencies to
provide input throughout the project.
5
MUNICIPAL CLASS ENVIRONMENTAL ASSESSMENT
(EA) PROCESS
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

6. Public Information
Centre 1: Fall 2016
• Overview of Study
• Problem Statement
• Existing Conditions
• Alternative Measures
• Evaluation Criteria
• Next Steps
Identification of Problem
or Opportunity
Evaluation of Alternative
Solutions & Identification
of Recommended
Solution
Selection of Preferred
Solution Following
Consultation Activities
Master Plan is Filed and
Posted for Public
Viewing: Winter 2017
Phase 1 Phase 2
Public Information
Centre 2:
Summer/Fall 2017
• Evaluation of Alternative
Measures
• Identification of
Preferred Solution
• Next Steps
Notice of Study
Commencement
Notice of Public
Information
Centre 1
Notice of Public
Information
Centre 2
Ongoing Public & Agency
Consultation throughout the
Study
Notice of Study
Completion
6
We are
here
Master Plans are conducted under the framework of the Municipal Engineers Association (MEA) Class EA process. They are long-
range plans that identify infrastructure requirements for existing and future land use within a larger study area, through the
application of EA principals.
MASTER PLAN PROCESS
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

7. • Collecting and reviewing background data on land use, population, soil conditions, sanitary sewer and storm
drainage systems, flooding history, and operation/maintenance records.
• Conducting surveys to inventory the number of roof leaders disconnected; survey catchbasins; identify low lying
areas; and conduct an inventory of storm outfalls.
• Developing and receiving feedback on potential measures to address the issue of basement and surface flooding
in the study area and to improve stormwater runoff water quality before it is discharged to the environment (1st
Public Information Centre).
• Developing computer models to:
- Analyze the causes of basement and surface flooding and predict flows under various weather conditions, and;
- Assess the impacts of stormwater runoff on water quality in Don River and its tributaries.
• Undertaking further assessment and refining measures.
• Presenting the recommended solution (at 2nd Public Information Centre) and finalizing the Master Plan based on
input from the public and agencies.
We are
here
7
STUDY OVERVIEW
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
The many steps involved in the study before solutions can be recommended include:

8. Problem Statement
• On August 19, 2005 the City of Toronto suffered from flooding of residents’
homes and damage to watercourses due to a large storm event.
• The City of Toronto has developed a work plan for an engineering review
to address the basement flooding concerns across 67 areas within the
city.
• Study Area 40 has been subject to basement and surface flooding
incidents during major historical storm events, reducing stormwater quality
and resulting in damage to properties, infrastructure, and natural features.
Objectives
• Identify potential causes of basement and surface flooding as they relate to the City’s storm and sanitary/combined
drainage infrastructure;
• Identify flooding interactions between the sanitary and storm drainage systems;
• Establish evaluation criteria;
• Propose works to improve the quality of water discharged to the environment;
• Propose surface and basement flooding remediation, stormwater runoff quality control and control alternatives;
• Identify and evaluate control alternatives to recommend a preferred solution; and,
• Prepare an infrastructure implementation phasing plan.
8
PROBLEM STATEMENT AND STUDY OBJECTIVE
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

9. • Urbanization has not only increased surface runoff and
decreased infiltration into the ground, but has also increased
the potential for the transport of pollutants via surface runoff
from streets, parking lots and other hard surfaces.
• Stormwater runoff often contains heavy metals, bacteria,
nitrates/sulfates, salt, sand, grit, oil/grease, trash, and other
pollutants.
• Pollutants in the stormwater runoff adversely impact the
water quality of the receiving watercourse, which affects
fisheries, wildlife, recreational uses, visual aesthetics, etc.
9
Don River
STORMWATER RUNOFF QUALTIY
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

10. • Area 40 is located in central Toronto and is serviced by a
combined sewer system, as well as separate storm and
sanitary systems.
• This area has experienced basement and surface flooding
incidents during severe storm events on May 12, 2000,
August 19, 2005, July 31, 2012, May 28, 2013 and July 8,
2013.
Characteristics Study Area 40
Study area size 1,642 hectares
Number of properties 24,241
Sanitary trunk sewer (STS) and
combined trunk sewer (CTS)
St. Ives CTS, Forman-Yonge CTS,
Greer CTS, Woburn STS, Fairfield
CTS, Otter Crescent STS, Avenue-
Manor CTS, Hillhurst STS, Castlewood
CTS, Balliol CTS
Major receiving watercourse Don River, Don River Tributary
Number of storm outfalls 8
Number of combined sewer outfall
(CSO) structures
6
10
Study Area 40
WELCOMESTUDY AREA 40
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

11. 11
Flooding Reports Map

12. 12
Sanitary Sewer System Map

13. 13
STORM SEWER SYSTEM
Storm Sewer System Map

14. • Storm sewers (minor system) convey frequent, small storms.
• Streets (major system) convey major storms that exceed the storm sewer capacity.
• Temporary ponding on streets is expected during major rain storms.
14
STORM DRAINAGE SYSTEM
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
Sanitary/Combined
Sewer Storm sewer to
convey frequent,
small storms
Street to convey stormwater
flows above storm sewer
design capacity
Street right-of-way

15. 15
POTENTIAL CAUSES OF FLOODING
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
Cracked
basement floor
and blocked or collapsed foundation drains

16. Under normal rainfall events, the storm, combined and sanitary sewer
systems operate as designed. However, during extreme storms, the
following takes place:
• Connected roof downspouts contribute to stormwater flows exceeding the storm, combined and
sanitary sewer capacity and overloading the system.
• Water remains on the surface and flows along roads and creeks. Surface water may enter
basements through basement doors, window sills, cracks in basement floors or walls, reverse-
sloped driveways and through sewer connections.
• At low lying areas, water accumulates (ponds) on the surface and enters the sanitary/combined
sewer system through manhole covers. This causes the sanitary/combined sewers to potentially
backup into basements.
• The ground becomes extremely wet and groundwater enters the sanitary/combined system
through cracks in the pipes underground. This can also contribute to backup of the
sanitary/combined sewers.
Other factors causing sewer backups:
• Foundation drains connected to the sanitary/combined sewer system;
• Cross-connections between the sanitary and storm sewer systems, and;
• Oil/grease dumped into sanitary sewers causing blockages.
16
POTENTIAL CAUSES OF FLOODING
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

17. General measures are presented. Detailed alternative solutions will be generated on a case-by-case review of the
City’s storm drainage and sanitary/combined sewer networks. This will take place at a later time in the Master Plan
Class EA process and will be presented at the second Public Information Centre.
• Source Controls
Measures involve managing stormwater where it originates (roofs,
roads, driveways), before it enters the City’s sewer pipes.
• Conveyance Controls
Measures to control stormwater as it travels along the sewer system
(in pipes or along the road).
• End-of-Pipe Controls
Measures to control stormwater just before it is discharged to the
receiver (watercourse, trunk sanitary or storm sewer).
17
MEASURES TO REDUCE BASEMENT FLOODING RISKS AND
IMPROVE STORMWATER RUNOFF QUALITY
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
Potential measures that will be considered to upgrade and expand the City’s
existing storm drainage and sanitary/combined sewer networks include:

18. Maintaining front and rear
yard drainage and
driveway catchbasins
Installing and maintaining
backwater valves and
sump pumps
Installing permeable
paving
Disconnecting roof
downspouts
Naturalizing the property
(rain gardens, green roofs) Installing rain barrels
18
POTENTIAL SOLUTIONS: PROPERTY OWNER
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
Residents can help reduce runoff – the water that flows from hard surfaces into the sewer system.
Naturalizing your property can improve stormwater runoff quality and may reduce the risk of basement flooding.
Source control solutions that can be implemented by property owners include:
• Eliminating pesticide/fertilizer use
• Ensuring household chemicals such as
paint, oil, grease, soap, etc. do not
wash into the storm sewer
• Picking up pet waste

19. Surface Flow Path Diversion
Surface drainage is directed away from low lying
areas that have no direct outlet to reduce surface
ponding depths.
“Curb cuts” can be added to redirect overland flow
to strategic locations.
Sealing Maintenance Hole
Covers
Maintenance hole covers with perforations in low
lying and ponding areas are sealed to reduce the
amount of stormwater runoff entering the
sanitary/combined sewer system and reduce the
risk of sanitary/combined sewer capacity overload.
These source control
options help to:
reduce the risk of
basement flooding
improve stormwater
runoff quality


19
POTENTIAL SOLUTIONS: SOURCE CONTROL
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

20. Replacement of Existing Storm
and/or Sanitary Sewers
Existing storm and/or sanitary sewers with
inadequate capacities to convey the required flows
are replaced with larger pipes.
Construction of New Sewers
Existing sewer pipes remain in place and a new
sewer pipe is installed to provide additional flow
capacity.
20
These conveyance
control options help to:
reduce the risk of
basement flooding
improve stormwater
runoff quality


POTENTIAL SOLUTIONS: CONVEYANCE CONTROL
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
Oversized Storage
Pipes
New oversized pipes are constructed
to temporarily store water and help
relieve overloading of the storm
sewer system.

21. Catchbasin Inlet
Control
Catchbasin inlet controls are
installed to limit stormwater
runoff entering the storm
system.
Increasing Catchbasins
For existing storm sewers having capacity,
the number of catchbasins are increased to
capture more flow from the surface.
21
These conveyance
control options help to:
reduce the risk of
basement flooding
improve stormwater
runoff quality


POTENTIAL SOLUTIONS: CONVEYANCE CONTROL
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

22. Infiltration/Exfiltration Systems
Stormwater conveyed in storm sewers can be released
underground via perforations (small holes) in the pipe to recharge
the water table.
22
These conveyance
control options help to:
reduce the risk of
basement flooding
improve stormwater
runoff quality

POTENTIAL SOLUTIONS: CONVEYANCE CONTROL
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40


23. Bioretention Units
Bioretention units are plant and soil based, and
provide low impact treatment and infiltration, for
treating stormwater runoff in developed areas.
Bioswales
Bioswales are landscape elements designed to
remove silt and pollution from stormwater runoff.
These are designed with specific soil mixtures,
surface plantings and underdrain within open
areas such as ditches, boulevards or parks.
Pervious Pavement
Pervious pavement is designed to allow
percolation or infiltration through the surface into
the soil below where the water is naturally
filtered and pollutants removed.
23
These conveyance
control options help to:
reduce the risk of
basement flooding
improve stormwater
runoff quality


POTENTIAL SOLUTIONS: CONVEYANCE CONTROL
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

24. Underground Storage
Tanks/Shafts
Dry Ponds Temporary storage of flows can be provided
underground using tanks/shafts (for storm and
sanitary/combined systems), or above ground using
dry ponds (storm drainage only). Once there are
adequate flow capacities in the sewer systems, the
flows from these storage facilities will be gradually
released. Furthermore, underground storage tanks
or shafts provide treatment for stormwater through
settling.
24
These end of pipe control
options help to:
reduce the risk of
basement flooding
improve stormwater
runoff quality


POTENTIAL SOLUTIONS: END-OF-PIPE CONTROLS
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40

25. Wet Ponds/ Constructed
Wetlands
Wet ponds and constructed wetlands are basins
that have a permanent pool of water throughout
the year to store runoff during and after storm
events. They treat and filter stormwater runoff
through settling and through nutrient uptake by
plants and other aquatic organisms.
Oil/Grit Separators
An oil/grit separator is an underground structure
connected to the storm sewer to improve
stormwater quality by removing contaminants
such as grease, oil, mud, sand and trash.
Wet ponds/constructed
wetlands help to:
reduce the risk of
basement flooding
improve stormwater
runoff quality
Oil/grit separators help to:
improve stormwater
quality



25Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
POTENTIAL SOLUTIONS: END-OF-PIPE CONTROLS

26. Natural Environment
Potential impacts on:
• Terrestrial systems (vegetation,
trees, wildlife)
• Aquatic systems (aquatic life
and vegetation)
• Surface and groundwater
• Soil and geology
• Receiving water quality
Socio-Cultural
• Land use impacts (parks, ravines,
open spaces)
• Disruption to existing community
during construction (traffic, noise)
and post-construction (visual
impact, odour, safety)
• Potential impacts to
archaeological and cultural
resources
• Impacts to First Nations
Technical
• Effectiveness in reducing surface
and basement flooding and
improving stormwater runoff quality
• Feasibility of implementation
(available space, accessibility,
constructability, approvals)
• Potential impacts on upstream,
downstream, and surrounding area
infrastructure
• Impacts on operating and
maintenance requirements
26
EVALUATION CRITERIA
Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
Economic
• Capital cost
• Operating and
maintenance
costs
Alternative solutions will be evaluated
based on their ability to address the
Study’s purpose, stakeholder input,
and their potential impacts.
Evaluation criteria being considered
include:

27. Thank you for attending this Public Information Centre.
Next Steps
• Please fill out a comment sheet.
• The study team will review and consider your comments in the evaluation of alternative measures.
• The recommended solution will be presented at the Public Information Centre #2 (Summer/Fall 2017).
Contact Information
If you have additional questions or comments please contact:
Ms. Mae Lee
Public Consultation Unit, City of Toronto
Metro Hall, 19th Floor, 55 John Street
Toronto, ON M5V 3C6
Tel: 416-392-8210
Fax: 416-392-2974
TTY: 416-338-0889
Email: rmlee@toronto.ca
Website: http://www.toronto.ca/bfea
27Basement Flooding Remediation and Water Quality Improvement Master Plan Class EA: Study Area 40
NEXT STEPS AND PROJECT CONTACT