my first experience in a developing
country was on a family vacation to
Bangkok Thailand when I was in high
school we went to on a canal boat ride
through the chao praya river through a
village on stilts and we’re cruising
along past the first house and someone’s
clearly just been doing their laundry in
the river right there in front of their
house and we go past the second house
and someone’s throwing garbage out of
the front door into the river right in
front of their house and you come along
to the next house and on the steps in
front of her house in the river is a
woman standing there brushing her teeth
it was pretty shocking to me as a 15
year old to see that people actually
lived like that and it struck me that if
these people had access to clean water
their lives would be vastly different
this was a really pivotal experience for
me sending me down my future Water
Resources engineering education and
research career path so not 15 anymore
and we’re here in the US and here now I
worry that we are not quite so far from
those kind of water quality conditions
as we’d like to think I do know that if
we maintain the status quo for
stormwater infrastructure design we will
go backwards I believe that a radical
shift in our approach to urban
stormwater infrastructure design is
essential for providing clean water for
our future in in this quest roof runoff
is critical and using green
infrastructure technologies offers us
the innovative solutions that we
desperately need the American Society of
Civil Engineers consistently gives our
nation’s aging infrastructure
a d-plus grade when it comes to
stormwater systems our existing in old
systems can no longer technically
address all the different ways that
stormwater runoff
impacts our day-to-day lives the design
of our existing infrastructure focuses
on big storms and big floods
and we haven’t paid attention to the
details you may not even notice when it
rains half an inch here or there except
maybe you forgot your umbrella about
hair day coming or maybe your clouds
have silver linings because the garden
always needs water
that’s my mom me I hate wet feet I have
four pairs of rain boots now this
becomes something of an occupational
hazard because I am out there measuring
rainfall and runoff all the time
our traditional urban drainage systems
whisk away stormwater runoff quickly and
efficiently it comes off of rooftops
down gutters and downspouts it comes off
of streets and sidewalks and parking
lots in to catch basins and down in to
buried pipes it’s out of sight and out
of mind all these water shedding
impervious surfaces are ubiquitous in
our built environment you know it only
takes a tenth of an inch of rainfall for
runoff to start flowing off of
impervious surfaces that’s less than
about a tablespoon of water and when we
couple that with statistics that tell us
that in the New Jersey and New York area
about 80% of our day-to-day rainfalls
are less than eight tenths of an inch
that’s like a couple of tablespoons what
that means is that we’re getting a lot
of runoff happening every time it rains
and that runoff is moving really quickly
through our systems now here in Hoboken
New Jersey or across the Hudson River in
New York City in Seattle Washington in
Portland Oregon and Milwaukee Wisconsin
in London in Paris in many older cities
around the world all that water flows
into what’s called a combined sewer
during dry weather the only flow in the
sewer is domestic sewage that’s what
goes down the drain or flush down the
toilet
now those pipes lead to a wastewater
treatment plant where that water is is
treated to safe levels in theory before
it’s discharged into the environment
during wet weather stormwater runoff and
also snowmelt also flows into the pipe
has the term combined sewer it’s a
single pipe that carries both stormwater
runoff and domestic sewage of most
concern to me and arguably
the most alarming for Public Health is
that the capacity of these combined
sewers can get overwhelmed even when it
rains just a few tenths of an inch just
those few tablespoons and in those
instances that mixture of domestic
sewage and stormwater runoff discharges
untreated and uncontrolled into the
nearest waterway it bypasses the
treatment plant this is called a
combined sewer overflow or CSO for
public health and the environment
it’s the domestic sewage that’s the
problem it contains high levels of
pathogens these are bacteria and viruses
and other microorganisms that can make
us sick so let’s be clear there’s a
water quality threat that’s caused by a
water quantity issue from the storm
water runoff that’s happening just about
every time it rains now not every city
has a combined sewer but for the cities
that do we’re starting to see public
warning signs pop up the cities that do
have combined sewer systems may have
more than one location where that CSO
pours out of the system this is called
an outfall San Francisco has 35 Chicago
has 39 Washington DC currently has 53
and Columbus Ohio currently has a
hundred and twenty-two outfalls pouring
into the Great Lakes New York State the
current number is 911 but this isn’t a
problem just for big cities the US
Environmental Protection Agency tells us
that there are currently about 772
communities that have combined sewer
systems but the majority of these serve
communities with fewer than 10,000
people but wait there’s more legally
under the federal Clean Water Act owners
and operators of the combined sewer
systems are required to decrease how
often a CSO can occur and how much water
can pour out of the system when it does
occur the price tag is stunning New York
City and Philadelphia are currently
looking at a billion dollars the city of
Omaha Nebraska has estimated 2 billion
across the state of New Jersey for our
217 out falls the current estimate is
anywhere from two to nine point three
billion dollars all of those were with a
B there is no do nothing option and the
taxpayer will bear the majority of the
cost okay so now I’ve probably grossed
you out
maybe I’ve bummed you out maybe got you
a little worried about your local taxes
there’s good news to share we have been
working really hard on solutions and
these solutions come as a forum a suite
of technologies that we call stormwater
green infrastructure from my perspective
stormwater green infrastructure is
natural and engineered systems we’ve
tipped the city’s water balance too far
out of whack to rely on pocket parks on
the corner or potted plants on a balcony
to manage runoff we need to help nature
work more effectively and more
efficiently our stormwater green
infrastructure needs to integrate into
the built environment we need to pack
function into compact forms that we can
retrofit into dense urban spaces
technically our stormwater green
infrastructure works by promoting
natural hydrologic processes we want to
soak up runoff slow it down and make it
available to plants to breathe back out
into the atmosphere sometimes our best
solutions come by maximizing stormwater
as a resource I don’t think it’s right
that we’re flushing toilets or washing
cars with water that’s clean enough to
drink altogether our stormwater green
infrastructure will improve water
quality and provide a wide range of
ecological community and infrastructure
services at its simplest technical
function stormwater green infrastructure
aims to keep runoff out of the sewer in
the first instance or to slow it down
and delay it for as long as possible in
the second because if we don’t have
runoff we don’t have a problem now
figuring out how to implement these
principles in the middle of a city
brings with it quite a few challenges
there’s not a lot of space available and
some
you know putting water into the ground
isn’t actually a good idea
you know we might cause another problem
like flooding out the subway I am always
looking around for ways to intercept
runoff I do get caught with my head
stuck down catch basins and looking up
downspouts and this got me thinking it
turns out that rooftops take up an awful
lot of space in the urban environment
we’ve measured here in Hoboken New
Jersey that rooftops are 57 percent of
the impervious area those are those
water shedding surfaces and rooftops are
45% of the total area of the entire city
so this means that rooftops are probably
our single largest source of runoff and
thinking strategically we should be
targeting our stormwater green
infrastructure for managing roof runoff
you may have heard of a green roof well
the first one that I built was mostly
yellow and later some of it turned pink
in my book it’s a living roof some of
the working parts in stormwater green
infrastructure are in fact alive and
this is what partly what makes green
infrastructure adaptable and resilient
to changing conditions with our storm
water living roofs our aim is to
eliminate the rooftop as a source of
runoff or at least minimize it as much
as possible and we do this by creating a
sponge on the roof now we are in a roof
so the building structural integrity and
public safety are still our number one
design priorities we build our sponge by
manipulating the materials that we use
for example we engineer the growing
media so that all we need is a thin
lightweight layer that can hold a lot of
water that’s our sponge right and the
plants we need to select plants that can
first of all survive but second of all
that can perform under pretty extreme
and highly variable conditions it’s
really exposed up there on a rooftop
it’s not at all like growing down at the
ground level we need those plants to
kick in after the storm to pump the
water back out into the atmosphere to
wring out our sponge so to speak so that
we can capture the next storm there are
going to be scenarios where a living
roof is just simply not a feasible
technology too many hva
see units on the rooftop too many
satellite dishes or sometimes you
physically just can’t even access the
roof to install a living roof so in
these situations we might consider using
something called the bioretention
planter so a bioretention planter sits
at grade underneath your downspouts and
water just comes charging down like a
waterfall down those downspouts into the
planter the technical aim of our
bioretention planters is to slow down
and delay the discharge of runoff it’s
like waiting for after rush hour to go
somewhere you know the runoff from the
rooftop is ultimately still going to get
into the sewer but it’s gonna be later
after the peak demand is passed these
are just two examples as I said
stormwater green infrastructure is a
suite of technologies and if we have
them available to us now why aren’t you
seeing them everywhere around you new
technologies are perceived as risky fear
the unknown resistance to change and in
particular with storm water green
infrastructure misperceptions about how
something works all the same old stories
from everywhere else in life apply here
even for something as critical as our
water going even further outside of our
comfort zones Engineers need to work in
interdisciplinary teams in a manner to
which we’ve never seen before in water
infrastructure from my own experience
working with a plant and soil scientist
and a landscape architect and consulting
with urban planners and social
scientists has forced me to view and
understand these technologies from
outside of my own disciplines
traditional lens I truly believe that
this has been the key to discovery in
innovation in design now it’s not all
about research it’s about all of you
because all of us have a role to play
you can start by making sure your roof
runoff maybe goes over your lawn better
yet install a cistern or a rain barrel
and harvest that storm water to water
your plants later because it doesn’t
rain every day even better still we can
all attend
planning board meetings or public
hearings for development we can write
letters or I guess we some emails now to
our city councils you see combined sewer
overflow mitigation is driven by
regulation but green stormwater
infrastructure implementation and its
long-term success is fostered by public
engagement it’s time to demand that
development rules catch up to the state
of the art because we have the
technology these days we are all about
multitasking with the living roof we can
partner a living roof with solar panels
and both systems work more efficiently
and more effectively we can use cisterns
to harvest storm water for non-potable
uses almost all storm water green
infrastructure provides amenity space it
creates urban ecosystems it’s been
proven to improve public health and
well-being and it moves us towards
environmental justice all the while our
stormwater green infrastructure is
protecting our waterways drop by drop I
challenge you to find another form of
infrastructure that can do all that thank you
country was on a family vacation to
Bangkok Thailand when I was in high
school we went to on a canal boat ride
through the chao praya river through a
village on stilts and we’re cruising
along past the first house and someone’s
clearly just been doing their laundry in
the river right there in front of their
house and we go past the second house
and someone’s throwing garbage out of
the front door into the river right in
front of their house and you come along
to the next house and on the steps in
front of her house in the river is a
woman standing there brushing her teeth
it was pretty shocking to me as a 15
year old to see that people actually
lived like that and it struck me that if
these people had access to clean water
their lives would be vastly different
this was a really pivotal experience for
me sending me down my future Water
Resources engineering education and
research career path so not 15 anymore
and we’re here in the US and here now I
worry that we are not quite so far from
those kind of water quality conditions
as we’d like to think I do know that if
we maintain the status quo for
stormwater infrastructure design we will
go backwards I believe that a radical
shift in our approach to urban
stormwater infrastructure design is
essential for providing clean water for
our future in in this quest roof runoff
is critical and using green
infrastructure technologies offers us
the innovative solutions that we
desperately need the American Society of
Civil Engineers consistently gives our
nation’s aging infrastructure
a d-plus grade when it comes to
stormwater systems our existing in old
systems can no longer technically
address all the different ways that
stormwater runoff
impacts our day-to-day lives the design
of our existing infrastructure focuses
on big storms and big floods
and we haven’t paid attention to the
details you may not even notice when it
rains half an inch here or there except
maybe you forgot your umbrella about
hair day coming or maybe your clouds
have silver linings because the garden
always needs water
that’s my mom me I hate wet feet I have
four pairs of rain boots now this
becomes something of an occupational
hazard because I am out there measuring
rainfall and runoff all the time
our traditional urban drainage systems
whisk away stormwater runoff quickly and
efficiently it comes off of rooftops
down gutters and downspouts it comes off
of streets and sidewalks and parking
lots in to catch basins and down in to
buried pipes it’s out of sight and out
of mind all these water shedding
impervious surfaces are ubiquitous in
our built environment you know it only
takes a tenth of an inch of rainfall for
runoff to start flowing off of
impervious surfaces that’s less than
about a tablespoon of water and when we
couple that with statistics that tell us
that in the New Jersey and New York area
about 80% of our day-to-day rainfalls
are less than eight tenths of an inch
that’s like a couple of tablespoons what
that means is that we’re getting a lot
of runoff happening every time it rains
and that runoff is moving really quickly
through our systems now here in Hoboken
New Jersey or across the Hudson River in
New York City in Seattle Washington in
Portland Oregon and Milwaukee Wisconsin
in London in Paris in many older cities
around the world all that water flows
into what’s called a combined sewer
during dry weather the only flow in the
sewer is domestic sewage that’s what
goes down the drain or flush down the
toilet
now those pipes lead to a wastewater
treatment plant where that water is is
treated to safe levels in theory before
it’s discharged into the environment
during wet weather stormwater runoff and
also snowmelt also flows into the pipe
has the term combined sewer it’s a
single pipe that carries both stormwater
runoff and domestic sewage of most
concern to me and arguably
the most alarming for Public Health is
that the capacity of these combined
sewers can get overwhelmed even when it
rains just a few tenths of an inch just
those few tablespoons and in those
instances that mixture of domestic
sewage and stormwater runoff discharges
untreated and uncontrolled into the
nearest waterway it bypasses the
treatment plant this is called a
combined sewer overflow or CSO for
public health and the environment
it’s the domestic sewage that’s the
problem it contains high levels of
pathogens these are bacteria and viruses
and other microorganisms that can make
us sick so let’s be clear there’s a
water quality threat that’s caused by a
water quantity issue from the storm
water runoff that’s happening just about
every time it rains now not every city
has a combined sewer but for the cities
that do we’re starting to see public
warning signs pop up the cities that do
have combined sewer systems may have
more than one location where that CSO
pours out of the system this is called
an outfall San Francisco has 35 Chicago
has 39 Washington DC currently has 53
and Columbus Ohio currently has a
hundred and twenty-two outfalls pouring
into the Great Lakes New York State the
current number is 911 but this isn’t a
problem just for big cities the US
Environmental Protection Agency tells us
that there are currently about 772
communities that have combined sewer
systems but the majority of these serve
communities with fewer than 10,000
people but wait there’s more legally
under the federal Clean Water Act owners
and operators of the combined sewer
systems are required to decrease how
often a CSO can occur and how much water
can pour out of the system when it does
occur the price tag is stunning New York
City and Philadelphia are currently
looking at a billion dollars the city of
Omaha Nebraska has estimated 2 billion
across the state of New Jersey for our
217 out falls the current estimate is
anywhere from two to nine point three
billion dollars all of those were with a
B there is no do nothing option and the
taxpayer will bear the majority of the
cost okay so now I’ve probably grossed
you out
maybe I’ve bummed you out maybe got you
a little worried about your local taxes
there’s good news to share we have been
working really hard on solutions and
these solutions come as a forum a suite
of technologies that we call stormwater
green infrastructure from my perspective
stormwater green infrastructure is
natural and engineered systems we’ve
tipped the city’s water balance too far
out of whack to rely on pocket parks on
the corner or potted plants on a balcony
to manage runoff we need to help nature
work more effectively and more
efficiently our stormwater green
infrastructure needs to integrate into
the built environment we need to pack
function into compact forms that we can
retrofit into dense urban spaces
technically our stormwater green
infrastructure works by promoting
natural hydrologic processes we want to
soak up runoff slow it down and make it
available to plants to breathe back out
into the atmosphere sometimes our best
solutions come by maximizing stormwater
as a resource I don’t think it’s right
that we’re flushing toilets or washing
cars with water that’s clean enough to
drink altogether our stormwater green
infrastructure will improve water
quality and provide a wide range of
ecological community and infrastructure
services at its simplest technical
function stormwater green infrastructure
aims to keep runoff out of the sewer in
the first instance or to slow it down
and delay it for as long as possible in
the second because if we don’t have
runoff we don’t have a problem now
figuring out how to implement these
principles in the middle of a city
brings with it quite a few challenges
there’s not a lot of space available and
some
you know putting water into the ground
isn’t actually a good idea
you know we might cause another problem
like flooding out the subway I am always
looking around for ways to intercept
runoff I do get caught with my head
stuck down catch basins and looking up
downspouts and this got me thinking it
turns out that rooftops take up an awful
lot of space in the urban environment
we’ve measured here in Hoboken New
Jersey that rooftops are 57 percent of
the impervious area those are those
water shedding surfaces and rooftops are
45% of the total area of the entire city
so this means that rooftops are probably
our single largest source of runoff and
thinking strategically we should be
targeting our stormwater green
infrastructure for managing roof runoff
you may have heard of a green roof well
the first one that I built was mostly
yellow and later some of it turned pink
in my book it’s a living roof some of
the working parts in stormwater green
infrastructure are in fact alive and
this is what partly what makes green
infrastructure adaptable and resilient
to changing conditions with our storm
water living roofs our aim is to
eliminate the rooftop as a source of
runoff or at least minimize it as much
as possible and we do this by creating a
sponge on the roof now we are in a roof
so the building structural integrity and
public safety are still our number one
design priorities we build our sponge by
manipulating the materials that we use
for example we engineer the growing
media so that all we need is a thin
lightweight layer that can hold a lot of
water that’s our sponge right and the
plants we need to select plants that can
first of all survive but second of all
that can perform under pretty extreme
and highly variable conditions it’s
really exposed up there on a rooftop
it’s not at all like growing down at the
ground level we need those plants to
kick in after the storm to pump the
water back out into the atmosphere to
wring out our sponge so to speak so that
we can capture the next storm there are
going to be scenarios where a living
roof is just simply not a feasible
technology too many hva
see units on the rooftop too many
satellite dishes or sometimes you
physically just can’t even access the
roof to install a living roof so in
these situations we might consider using
something called the bioretention
planter so a bioretention planter sits
at grade underneath your downspouts and
water just comes charging down like a
waterfall down those downspouts into the
planter the technical aim of our
bioretention planters is to slow down
and delay the discharge of runoff it’s
like waiting for after rush hour to go
somewhere you know the runoff from the
rooftop is ultimately still going to get
into the sewer but it’s gonna be later
after the peak demand is passed these
are just two examples as I said
stormwater green infrastructure is a
suite of technologies and if we have
them available to us now why aren’t you
seeing them everywhere around you new
technologies are perceived as risky fear
the unknown resistance to change and in
particular with storm water green
infrastructure misperceptions about how
something works all the same old stories
from everywhere else in life apply here
even for something as critical as our
water going even further outside of our
comfort zones Engineers need to work in
interdisciplinary teams in a manner to
which we’ve never seen before in water
infrastructure from my own experience
working with a plant and soil scientist
and a landscape architect and consulting
with urban planners and social
scientists has forced me to view and
understand these technologies from
outside of my own disciplines
traditional lens I truly believe that
this has been the key to discovery in
innovation in design now it’s not all
about research it’s about all of you
because all of us have a role to play
you can start by making sure your roof
runoff maybe goes over your lawn better
yet install a cistern or a rain barrel
and harvest that storm water to water
your plants later because it doesn’t
rain every day even better still we can
all attend
planning board meetings or public
hearings for development we can write
letters or I guess we some emails now to
our city councils you see combined sewer
overflow mitigation is driven by
regulation but green stormwater
infrastructure implementation and its
long-term success is fostered by public
engagement it’s time to demand that
development rules catch up to the state
of the art because we have the
technology these days we are all about
multitasking with the living roof we can
partner a living roof with solar panels
and both systems work more efficiently
and more effectively we can use cisterns
to harvest storm water for non-potable
uses almost all storm water green
infrastructure provides amenity space it
creates urban ecosystems it’s been
proven to improve public health and
well-being and it moves us towards
environmental justice all the while our
stormwater green infrastructure is
protecting our waterways drop by drop I
challenge you to find another form of
infrastructure that can do all that thank you
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