Mitigating Urban Flood Risk in New Residential … · 12.09.2016 · 3 © Amec Foster Wheeler 2016...
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© Amec Foster Wheeler 2016. 12 September 2016 ENVIRONMENT & INFRASTRUCTURE Peter Nimmrichter, M.Eng., P.Eng. Associate and Climate Change Specialist, Water Resources Burlington, Ontario, Canada Inflow/Infiltration and Stormwater Mitigating Urban Flood Risk in New Residential Subdivisions
Transcript of Mitigating Urban Flood Risk in New Residential … · 12.09.2016 · 3 © Amec Foster Wheeler 2016...
© Amec Foster Wheeler 2016.
12 September 2016
ENVIRONMENT & INFRASTRUCTURE
Peter Nimmrichter, M.Eng., P.Eng.
Associate and Climate Change Specialist, Water Resources
Burlington, Ontario, Canada
Inflow/Infiltration and Stormwater
Mitigating Urban Flood Risk in
New Residential Subdivisions
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Project Overview
The next step from the Best
Practices Guide: Management of
Inflow and Infiltration in Urban
Developments (February 2015)
Taking the next step with a focus on
I&I issues and stormwater
management issues
Capacity building towards flood
resilience in new urban residential
developments
Developing a guidance document
outlining urban flooding best
management practices for new
urban residential developments
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Problems … I&I
Inflow and Infiltration
leading to flooding
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Problems … I&I
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Problems … I&I
Source: http://www.kwl.ca/sites/default/files/IandI-paper-OCR.pdf
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Inflow & Infiltration Issues …The process
Design/
SpecificationConstruction Inspection
Acceptance/ Transfer
Operations / Maintenance
Full life cycle design
Specifications to ensure objectives
Use of required materials
Good construction practices
Proper training
Adequate inspection procedures
Adequate monitoring
Proper training
Contract
language
Assumed period of consideration for study
Proactive
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Inflow & Infiltration Issues …But not in New Construction
Blue text - Inflow
Red text - Infiltration
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Inflow & Infiltration Issues …We’ve always known about it
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Problems … I&I
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Majority of problems experienced with private laterals originate from initial construction
Private property sources contribute ~40% of total system I&I
A significant amount of I&I from new subdivisions due to poor workmanship and
construction loads
Chimney frame leaks are one of the most significant sources of extra stormwater into
the sanitary system
I&I control in new developments is most cost effective, as deficiencies can be fixed
prior to assumption of sewers by municipalities
Enforcing and raising the construction standards including updating the Sanitary
Sewer System Inspection requirements, Testing and Acceptance Guidelines in
collaboration with municipal partners and undertaking flow monitoring in new
developments are instrumental to continued improvement
Homeowner education
Opportunities to engage homeowners when property is up for sale
Inflow & Infiltration Issues …Some current knowledge
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Problems … I&I
If we don’t ask for
what we really want
we may not get it.
If we don’t check
that we’re getting
what we asked for
we may not get it.
Technologies exists
to mitigate I&I
issues … are we
using them ?
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Problems … Stormwater
Storm sewer surcharging
leading to flooding
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Stormwater Issues …
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Stormwater Issues …Scale – Watershed/Subdivision
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Stormwater Issues …Scale – Watershed/Subdivision
Stormwater system design / stress testing
100 year, 350 year, 500 year, Regional Storm
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Stormwater Issues …Scale – Lot Level
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Stormwater Issues …Scale – Lot Level
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Rainfall is increasing …
Current: 1963 IDF Curve
2012 IDF Curve
1.0
10.0
100.0
1000.0
5 10 15 30 1 2 6 12 24
Inte
snit
y (m
m/h
r)
Duration (min/hour)
2020 or 2050 IDF Curve
Stormwater Issues …Climate Change
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Problems … Stormwater
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Inflow & Infiltration Issues …
Lisgar District Basement Water Infiltration Investigation
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Stormwater Issues …Resistance/Resilience
Permanent resistance measures designed to
stop water entering your home either through
existing openings or to stop it penetrating the
walls.
Temporary resistance measures aim to keep
floodwater out of a building by putting in place
devices that block floodwater ingress.
Resilience measures allow a building to flood but
constructing the interior from materials that are
not damaged by water.
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Stormwater Issues …Resistance/Resilience
Thank you!
23 © Amec Foster Wheeler 2016
ENVIRONMENT & INFRASTRUCTURE
Peter Nimmrichter, M.Eng., P.Eng.
Associate and Climate Change Specialist, Water Resources
Burlington, Ontario, Canada
