Best method in Urban drainage management.

1. BEST & BAD URBAN DRAINAGE
PRACTICES
Lasisi Adedoyin K. S

2. Outline
● Introduction
● What is Urban Drainage?
● The Importance of Proper Urban
Drainage
● Best Practices for Urban Drainage
● Green Infrastructure
● Low-Impact Development
● Rain Barrels
● Green Roofs
● Permeable Pavement
● Rain Gardens
● Bad Urban Drainage Practices
● Stormwater Runoff

3. Outline
● Combined Sewer Overflows
● Inadequate Infrastructure
● The Costs of Bad Urban Drainage
Practices
● Case Studies

4. Learning
outcomes
• Understand urban drainage system
• Understand the important of proper
urban drainage system
• understand best urban drainage
system
• Cost of bad urban drainage system

5. Introduction
Urban drainage may not be the most
exciting topic, but it's crucial for
maintaining a healthy and safe
environment. Without proper
drainage, cities can experience
flooding, water pollution, and other
negative consequences. So let's
dive in and explore this important
topic together.
Urban drainage refers to the
management of stormwater runoff
in urban areas. This includes the
collection, conveyance, treatment,
and disposal of rainwater and other
forms of precipitation. Proper urban
drainage is essential for preventing
flooding, erosion, and water
pollution.

6. Introduction
● In urban areas, impervious
surfaces such as roads,
buildings, and sidewalks prevent
rainwater from soaking into the
ground. Instead, it flows over
these surfaces and into storm
drains, which can become
overwhelmed during heavy
rainfall. Without proper urban
drainage, this excess water can
cause significant damage to
infrastructure and property, as
well as endanger the health and
safety of residents.

7. The Importance
of Proper Urban
Drainage
Proper urban drainage is essential for
the health and safety of cities and their
inhabitants. Without effective drainage
systems, heavy rainfall can lead to
flooding, which can cause damage to
homes, businesses, and infrastructure.
In addition, standing water can create
breeding grounds for mosquitoes and
other pests, increasing the risk of
disease.

8. The
Importance of
Proper Urban
Drainage
Proper drainage also helps to
prevent water pollution. When
rainwater runs off surfaces like
roads and rooftops, it can pick up
pollutants like oil, fertilizers, and
pesticides. Without proper
drainage, this contaminated water
can enter rivers, lakes, and other
bodies of water, harming aquatic
life and making the water unsafe
for human use.

9. Best Practices
for Urban
Drainage
Green infrastructure and low-impact
development are two of the best
practices for urban drainage. Green
infrastructure involves using natural
systems like plants and soil to manage
stormwater, while low-impact
development techniques aim to
minimize the impact of development on
the environment. Both of these practices
help reduce the amount of stormwater
runoff that enters our sewer systems.

10. Green
Infrastructure
• Green infrastructure
refers to the use of
natural systems, such
as vegetation and soil,
to manage water in
urban areas. This can
include green roofs,
rain gardens, and
permeable pavement.

11. Sources: Green Infrastructure | BREC.org

12. Green
Infrastructure
● By using green infrastructure for
urban drainage, cities can
reduce the amount of
stormwater runoff that enters
their sewer systems, which can
help prevent flooding and water
pollution. Additionally, green
infrastructure can provide other
benefits, such as improving air
quality and providing habitat for
wildlife.

13. Green
Infrastructure
● One example of green
infrastructure is the use of rain
gardens, which are designed to
capture and filter stormwater.
Low-impact development
techniques include permeable
pavement, which allows
rainwater to seep through the
surface and into the ground
instead of running off into the
streets. These practices not only
help manage stormwater, but
also provide other benefits like
improved air quality and
increased property values.

14. Low-Impact
Development
● Low-impact development
(LID) is an approach to
urban design that
emphasizes the use of
natural systems to
manage stormwater
runoff. This can include
features like green roofs,
rain gardens, and
permeable pavement.

15. Courtesy Pierce County, Washington / WSU Extension

16. Low-Impact
Development
● The goal of LID is to reduce the
amount of stormwater that
enters the sewer system, which
can help prevent flooding and
reduce water pollution. By using
natural systems to manage
stormwater, LID can also help
create more attractive and
sustainable urban environments.

17. Rain Barrels
Rain barrels are an effective
way to manage stormwater
runoff in urban areas. By
collecting rainwater from
rooftops, the water can be
stored and reused for irrigation
or other non-potable uses. This
reduces the amount of
stormwater runoff that enters
our streets and sewer systems,
which can lead to flooding and
water pollution.

18. DIY Stacked Rain Barrel System Plans - Big Living | Little Footprint
(biglivinglittlefootprint.com)

19. Rain Barrels
In addition to their practical
benefits, rain barrels can also be
aesthetically pleasing. They come
in a variety of styles and colors, and
can even be decorated to match
the surrounding landscape.
Installing a rain barrel is a simple
and affordable way to make a
positive impact on your
community's urban drainage
system.

20. Green Roofs
Green roofs are an
innovative solution for
urban drainage. They
involve covering rooftops
with plants, which absorb
rainwater and release it
slowly into the
environment.

21. The Max Planck Institute for
the Structure and Dynamics of
Matter in Hamburg.
Source: Landschaftsarchitektur
The winner "BuGG Green Roof of the Year" 2021 is announced! - World Green
Infrastructure Network. www. world green infranstructure.org
Not only do green roofs help manage
stormwater runoff, they also provide
benefits such as reducing energy costs,
improving air quality, and creating
habitats for wildlife.

22. Permeable
Pavement
Permeable pavement is a type of
pavement that allows water to pass
through it and into the ground below.
This is achieved through the use of
materials such as porous concrete,
permeable asphalt, or interlocking
pavers with gaps between them.

23. Pervious Pavement | National Association of City Transportation Officials (nacto.org)

24. Permeable
Pavement
Permeable pavement can be used in
urban areas for a variety of purposes,
including reducing stormwater runoff,
replenishing groundwater supplies,
and reducing the urban heat island
effect. It can also help to reduce the
need for traditional stormwater
management systems, which can be
expensive and require a lot of
maintenance.

25. Rain Gardens
Rain gardens are a type of green
infrastructure that can help manage
stormwater runoff in urban areas.
They are designed to capture and
filter rainwater, allowing it to slowly
infiltrate into the ground rather than
flowing into storm drains and
contributing to flooding.

26. Gardening For Rainwater: Creating a Rain Garden | www.Saverainwater.com

27. Rain Gardens
Rain gardens are typically planted with
native vegetation that can tolerate both
wet and dry conditions. This vegetation
helps to further filter the water, removing
pollutants and improving water quality. In
addition to their functional benefits, rain
gardens can also add aesthetic value to
urban landscapes.

28. Bad Urban
Drainage
Practices
Bad urban drainage practices
can have severe
consequences for cities and
their inhabitants. Flooding is a
common result of poor
drainage, which can cause
property damage and even
threaten human lives.
Additionally, water pollution
can occur when rainwater
mixes with sewage or other
contaminants on its way to
drainage systems.

29. It is important for cities to
prioritize proper urban drainage
practices in order to avoid
these negative outcomes. This
includes investing in
infrastructure that can handle
heavy rainfall and implementing
green infrastructure solutions
like rain gardens and permeable
pavement.
Bad Urban
Drainage
Practices

30. Storm water
Runoff
Storm water runoff occurs when
precipitation from rain or
snowmelt flows over the ground
instead of being absorbed into
the soil. This water can pick up
pollutants like oil, fertilizers, and
pesticides, which can then be
carried into storm drains and
eventually end up in rivers, lakes,
and other bodies of water.

31. Storm water
Runoff
The impact of stormwater runoff on
urban drainage can be significant.
When there is too much runoff, it can
overwhelm stormwater management
systems and cause flooding.
Additionally, the pollutants carried by
the runoff can harm aquatic life and
make bodies of water unsafe for
swimming and other recreational
activities.

32. Combined
Sewer
Overflows
Combined sewer overflows (CSOs)
occur when stormwater runoff and
sewage are combined in a single
pipe system. During heavy rainfall,
the volume of water can exceed
the capacity of the system, causing
untreated sewage to overflow into
nearby bodies of water. This can
lead to serious health and
environmental problems, including
water pollution and the spread of
disease.

33. Combined
Sewer
Overflows
To combat CSOs, cities can
implement green infrastructure
solutions such as rain gardens and
permeable pavement. These
systems help to capture and filter
stormwater runoff before it enters
the sewer system, reducing the risk
of overflows. It's important for
cities to prioritize these solutions
and invest in proper infrastructure
to prevent the negative impacts of
CSOs.

34. Inadequate
Infrastructure
Inadequate infrastructure
can have a devastating
impact on urban drainage
systems. When pipes and
other structures are not
properly maintained, they
can become clogged with
debris or even collapse,
leading to flooding and
other issues.

35. Inadequate
Infrastructure
Additionally, outdated
infrastructure may not be
equipped to handle the
increased volume of
stormwater runoff that comes
with urbanization. This can
lead to overwhelmed systems
and backups that cause
pollution and health hazards.

36. The Costs of
Bad Urban
Drainage
Practices
Bad urban drainage practices can
have significant economic and
environmental costs. When cities
experience flooding due to poor
drainage, it can cause damage to
homes, businesses, and
infrastructure. This can result in
costly repairs and lost revenue for
affected individuals and the city as
a whole.

37. The Costs of
Bad Urban
Drainage
Practices
In addition to economic costs,
bad urban drainage practices can
also have negative environmental
impacts. When stormwater runoff
is not properly managed, it can
lead to water pollution and harm
aquatic ecosystems. This can
have long-term consequences for
the environment and the health of
both humans and wildlife.

38. Case studies:
Chicago
Chicago has been a leader
in implementing green
infrastructure initiatives to
improve urban drainage.
One of their most notable
projects is the Chicago
Riverwalk, which includes
features like permeable
pavement and rain
gardens to capture
stormwater runoff.

39. Case studies:
Chicago
In addition to the Riverwalk,
Chicago has also implemented
green roofs on many of its
buildings and created
bioswales along streets to
capture stormwater. These
initiatives not only improve
urban drainage, but also
provide benefits like improved
air quality and reduced urban
heat island effect.

40. Case studies:
Portland
Portland, Oregon is a city that
has been at the forefront of
low-impact development
initiatives. These initiatives
have focused on reducing the
impact of urban development
on the environment by using
innovative techniques to
manage stormwater runoff.

41. Sustainable
Drainage
Systems
Sustainable drainage
systems (SuDS) are
designed to manage
stormwater locally (as
close its source as
possible), to mimic
natural drainage and
encourage its infiltration,
attenuation and passive
treatment

42. Ever wondered
where the rain
goes_
Sustainable
drainage
animation.mp4

43. SuDS principle Sustainable drainage is a
departure from the
traditional approach to
draining sites. There are
some key principles that
influence the planning and
design process enabling
SuDS to mimic natural
drainage by:

44. SuDS principle
● storing runoff and releasing
it slowly (attenuation)
● harvesting and using the
rain close to where it falls
● allowing water to soak into
the ground (infiltration)
● Slowly transporting
(conveying) water on the
surface
● filtering out pollutants
● allowing sediments to settle
out by controlling the flow of
the water

45. Benefits of
SuDS
● flood risk management – reducing the
risk of flooding from development
● water quality management – reducing
the impact of diffuse pollution
● improving amenity and biodiversity –
the integration of green infrastructure
with SuDS solutions can help to create
habitat, recreational and biodiversity
areas
● water resources – SuDS can help to
recharge groundwater supplies and
capture rainwater for re-use purposes

46. Benefits of
SuDS
● community benefits – attractive, well designed public
open space that incorporate SuDS can help to create
better communities through social cohesion and
quality of life improvements
● recreation – multi-purpose SuDS components can
not only manage surface water, but also act as
sports/play areas
● education – SuDS in schools provide a fantastic
learning opportunity whilst also providing additional
recreational space
● enabling development – SuDS can help to free up
capacity in already established drainage networks,
and the provision of SuDS can often be a prerequisite
of planning permission.

47. Final word
In conclusion, we have learned that
proper urban drainage is crucial for
cities and their inhabitants. It helps
prevent flooding, water pollution, and
other negative consequences. By
implementing best practices such as
green infrastructure and low-impact
development, we can improve urban
drainage and create healthier, more
sustainable communities.

48. Final word
It's important to remember that bad
urban drainage practices come at a
high cost, both economically and
environmentally. By taking action
and supporting good urban
drainage practices, we can make a
positive impact on our
communities and the planet as a
whole.