So what I'd like to do is talk about an area that I work in.
And when I'm asked what I do, the two-word answer
is, I'm a water engineer.
And what does that mean?
It means that I work on water.
Is there enough of it?
And is it safe to drink?
So that's what I work on.
I also am the director of the National Science Foundation
Engineering Research Center for Re-inventing the Nation's Urban
Water Infrastructure.
And we're in our sixth year now.
We call ourselves the ReNEWIt.
It's a collaboration between Stanford, Berkeley,
Colorado School of Mines, and New Mexico State.
So what I'll be talking about here
is reinventing water supply for dry cities.
Let's use example of California.
And I'll be drawing also from some work
that we're doing in our engineering research center
as well.
So my take home message is today that when
we talk about water and water problems,
all of our solutions and the problems are local.
And what I mean by that is that the Bay Area has its water
challenges that are quite different than say Southern
California, that are different than San Diego, that are
different than the front range.
And the reason for this is because of climate conditions
and also because of existing infrastructure and politics
and policies.
I'd like to use examples though from California
to show how we can have a better water supply future by reducing
dependence on imported water.
You may know that the water that comes to the Stanford campus
is imported from Yosemite National Park
through an aqueduct system.
And that the way we can reduce dependency on imported water
is to have a portfolio of options for our water supply
in the future.
Or another way of saying that, there isn't just one thing we
can do, or should do.
There's several things we ought to pay attention to.
There isn't one specific thing that we
can do that will solve our water problems.
And in looking to the future, we need partnerships to evaluate
ideas at a believable scale.
And we call that a testbed or pilot plant.
And we also need decision support tools.
In other words, to ask the question,
well, if we are successful with a new technology
or new approach, how does that build out?
How does that technology diffuse?
So that's-- these are the main messages today.
But I thought I would start with the slide that says where do we
get our water in California?
This is what happens in a wet year.
We can say that this is our like currently.
Our water comes from three sources.
One of them is snow pack, snow melt.
And this year we have a generous snow pack.
We also get water from the ground and from reservoirs.
So when you think of reservoirs as just like rain
that's collected.
And in a normal year, these contribute about equally
to our water supply in California.
And I show the snow pack, the cloud, the reservoirs,
and the ground water is pretty high.
But, well you know, we've just experienced
five years of drought.
And what happens here then is this picture changes.
There's now snow pack.
There's not much rain.
The reservoirs are empty.
And we rely on groundwater to make up the deficits.
And the ground water, the water table as we call it, drops.
So that's what happens in a dry year.
Now in the 20th century, I would say
that we sort of limped around.
When we got into a drought, you hoped that well,
if we can get by for a few years, that will solve--
our problems will be solved when it starts raining again.
But in the 21st century, we realize
we're really at the edge, at the limit of what the existing
infrastructure can provide in terms of our water.
And often times when we think about water and solutions
for the future, it might be tempting to say,
our water problems would be solved if--
and then you would point to somebody or some place.
You know, if they would change their behavior then
we wouldn't have our problem.
And since I'm pointing south, I could
say, you know, the problem are those homes in Beverly
Hills with those big-- you know, if they
didn't wash their cars every day, everything would be fine.
Well, another-- the reality is we're all part of the problems
and we're all part of the solution.
We're all part of the problem.
We're all part of the solution.
And Governor Brown has emphasized this.
This is in 2015.
Now this was when the drought emergency was declared.
"The metaphor is Spaceship Earth," Brown said.
"In Spaceship Earth you reduce everything."
And he's basically saying we all have to work together
to solve the problem.
And he uses this analogy of Spaceship Earth.
Now I was just finishing graduate school
when Governor Brown was running for presidency.
This is-- you have to go back a few years now.
But he used that expression "Spaceship Earth,"
and he got the moniker Governor Moonbeam.
Now back then if you said weird things,
it really did kick you out of the election.
You were-- [LAUGHS] and so he got Governor Moonbeam.
And I think his candidacy lasted two months.
But the way I look at this then is from '76
to '17, look at all those years that have intervened.
Now no one's laughing.
We actually see that there is a--
we understand, at least in terms of water,
that we do have to think collectively and work
collectively on our problems.
So this is a schematic that shows how we designed our water
systems in the 20th century.
Basically it's taking water from say a reservoir,
or river, or ground water, treating it,
using it in the city.
The city will have runoff and waste water.
Treat that, and then it's discharge.
So it's kind of like a one pass of water.
Now in the 20th century--
or excuse me, the 21st century--
we have a different look at this.
We think about recycling water, collecting stormwater,
and so this drawing gets a little more complicated now.
Where the wastewater can be treated to a high degree,
it could be reused for potable or maybe
a potable or non-potable uses.
It could go in the ground and then
that way find its back into our water supply.
We can take runoff, which is storm water, which
we have a lot of.
We've had a lot of this winter.
Think about ways of collecting that, treating it, and making
that be part of our water supply.
And that's a source of water we haven't used before,
particularly in California, where the focus on storm water
has been on flood control management.
In other words, getting it to the ocean or bay as quick
as you could.
So the 21st century then is this one of closing the loops.
Now how do we actually implement this?
And where does the vision come for any particular city?
And I am going to use the example from California
that, to me, illustrates the power of local governance
and that, if we look at some mayors in our state,
they're actually forward-looking and are thinking,
we have to solve our problems.
Here you can look at Mayor Faulconer in San Diego.
And this is not the desal plant in Carlsbad.
But this is a water recycling facility
that they're testing now to take wastewater then
put it into a reservoir.
And from a reservoir, it would then
become part of the water supply.
Or Mayor Garcetti in Los Angeles--
Los Angeles has the objective of reducing their need
for imported water by half.
And what Mayor Garcetti-- a previous mayor set that goal,
and what Mayor Garcetti did was advance the time
for that by 10 years.
So Los Angeles is dependent for a large part of its water
coming from Northern California or from the Colorado River.
And so what Mayor Garcetti is saying,
in the future we want to reduce our dependence
on those sources, reduce dependency by half.
And that has to be made up by water recycling
and by storm water capture.
Or Mayor Sam Liccardo here in San Jose now--
this is where I'm taking my class this afternoon
for a tour of the Silicon Valley Advanced Water Purification
Facility.
That's a lot of words strung together.
But what is being done here is wastewater
from the big San Jose-Santa Clara treatment
plant is being processed through a series of steps
to produce water that's essentially
drinking water quality.
And I guess Mayor Sam here is getting
ready to show that you can actually drink that.
But the point is that this is where I think the action is
and where cities and counties see
the need to be aggressive in terms
of how they think about the future of their water supplies
and say we have to move on our own accord, of course,
being very thoughtful.
Now to put this in context, in the year and the era in which I
was a graduate student and had just became a professor,
the federal government took had a big role,
through the Clean Water Act and the Safe Drinking Water Act,
in building infrastructure for water treatment and wastewater
treatment.
Those days are over.
We're just not going to see them again.
In fact, I guess we could say, from Washington we just
haven't had a lot of guidance.
And so here is the cities taking the action themselves,
or the governor.
You can look at Governor Brown studying this drought
declaration and asking everyone to cut back
on their use of water.
So when we think about the future of the water supply,
an example I'll use here is the idea
of four faucet taps, where you could think water coming
from storm water harvesting.
This would be the water that you would see on your city streets
and concrete channels going to the ocean or the Bay;
water reuse, and being much more aggressive
about that; water use efficiency;
and then desalination.
Now desalination means getting the salt out of water.
It doesn't have to be sea water.
It could be water that's just a little too
salty for potable use.
So let's take a look at one of these.
This is the water use efficiency.
When I give talks to the general public about the water
futures for California, something
that always comes up first is, well what if we just
use a little less water?
Can we conserve our way out of the problem?
And then Governor Brown asked all the urban areas
to reduce their water use by 25% in 2015 to 2016.
And so this is a report from the state water resources control
board that shows that essentially for each month--
the average over all those months
is we really did achieve this 25% statewide reduction
in urban use of water.
And that comes from conservation.
It comes from paying attention to how we use water
for landscaping-- that's a major thing in our area--
and then not being wasteful.
There are other programs like installing
low-flow or low-flush toilets and that sort of thing.
But the main place where we could make a difference here
is being thoughtful about repairing leaks, not taking
long showers, and thinking about the outdoor use of water.
So that's the good news.
Well, I live on the Stanford campus.
I live about a half a mile that way.
And then I got this interesting letter this summer.
And this letter is from Joe Stagner.
And he says, "dear Dick, you've done
such a great job of conserving water by 25%,
I'm going to have to raise your rates by 29%."
So there it is.
This is to the campus users, "residential lease holders
may increase 29%.
The rate increase is due to the decrease in water use."
And so as my neighbor professor [INAUDIBLE] says,
is there anything that we use less of and we pay more for?
Well, you know, I think the analogy
is we're all used to the gas pump at the gas station.
If you get a more fuel efficient car,
you don't pay as much for your gas.
But what happens with the water is
it's not priced appropriately.
Our water charges are on dollars per 1,000 gallons.
So even if I use no water, we still
have to pay for the pipes and pumps that
are in the street and the staff to keep all of that going.
On the Stanford campus--
and I wrote a-- by the way, if you
want to read an editorial about this, you can do that.
On the Stanford campus, about one third of our water bill
is for the water.
The other 2/3 is for all the infrastructure.
So this is an issue here that comes up,
that if we use less water, we're going
to have to change the way in which we price water so that we
pay for the commodity part of it,
and we pay for the fixed costs part of it.
But you know, intellectually we kind of know this.
But it's another thing to get a letter like that in the mail.
And you say, yes, it hits home.
So let's take a look at stormwater harvesting.
Now I mentioned stormwater harvesting
means collecting the runoff from the urban area,
and capturing it, and treating it, and using it
in a way that can contribute to our water supply.
We don't really do that in Northern California.
In Southern California there's some spreading basins
like this.
This Is the Rio Hondo spreading basin.
It's near the San Gabriel River.
There are a series of spreading basins
right near the base of the San Gabriel Mountains.
So for reference, it would be like
if you were in downtown LA, not look towards the ocean,
but look back towards the mountains,
and those spreading basins are inland about 20 miles
from the ocean, roughly.
And these were built some years ago
to capture water behind dams and then release this
into places where the geology is right to help replenish
the aquifers that supply the water for Los Angeles.
But the distance from here to the ocean-- in other words,
that sort of top part of the picture-- that distances
is about 20 miles.
And that's where the--
that stormwater is not captured.
That's the water that falls on the urban hardscape, the roofs,
the driveways, industrial property, freeways,
and the like.
And that water is not captured.
And that's an opportunity for us in the future.
So this is a plot that shows, for the city of Los Angeles,
where they are today with the capture of water
in spreading basins and incidental recharge.
Now you don't have to pay so much attention to the units
here.
It's in thousands of acre feet.
But this shows where the city could
be with a sort of a conservative approach
to additional stormwater capture or a more aggressive approach
to stormwater capture.
The point is is that if you're sort
of aggressive on the stormwater capture side,
you could provide maybe a quarter
or so of the water for the city of Los Angeles.
And that's water that's currently not being used.
So when Mayor Garcetti says we'd like
to cut our requirement for imported water by half,
a majority of that could come just from capturing stormwater
that's not being caught today.
Now there's several problems with capture of stormwater.
One of them has to do with scale and costs.
Some of you may be familiar with rain barrels.
Rain barrels and small cisterns actually
don't work in our climate, in a Mediterranean climate.
The reason is is because they will fill up like recently
with the rains.
But you need that water later.
You need it like six or eight months later.
So you need a storage device.
So if you look at the cost here.
And this is a scale of cost per acre foot
against acre feet captured.
These larger systems, like I just showed,
are very cost efficient.
Smaller systems at the scale of a home, or street,
or neighborhood are attractive for public support
and engagement.
And also not every system in the city can be big like that.
The land doesn't exist really to do those great big ones
anymore.
But you get the idea here that, if I
want to make a difference in the amount of water that I catch,
I need sort of neighborhood and bigger scale systems.
But to gain public support for this,
you also need to do things at the scale
of a street with curbs, and plantings,
and that sort of thing.
There's another issue here, and that's the one of storage.
Now here I'm showing a picture of a cistern that
was built for an environmental group in Los Angeles.
The environmental group is called TreePeople.
It's kind of a funny name, but they're very influential.
They used to have a long name, which I don't even remember.
But when they would tell people what they did,
they said, oh, you're the people that plant the trees.
And so they changed their name to TreePeople,
That's what they did.
But anyway, with assistance from LA Department
of Water and Power, they built this stormwater collection
basin here at their visitor's center.
So this is like an educational facility.
And it shows what can happen if you can capture the stormwater.
And they can use that captured stormwater
then for irrigation of the trees around their property.
The problem is, it's just too much--
it's too expensive to do that.
Another one is there's a question of contaminants
here, where we have--
in urban runoff, we have a whole series
of chemicals that come from automobile
tires, and industrial facilities, and the like.
So an approach then for the future
would be to think about a system that
would comprise a capture, a treat, and a recharge.
And I show this in an engineering sense here.
But what might this look like?
This is a site we're working in Los Angeles, where
we are working with the city and the Bureau of Sanitation,
the flood control district, to convert a large former rock
quarry into a stormwater capture treatment system.
And you can see that when this is built out,
it looks very park-like.
You have a reservoir there, are wetlands, and play fields,
and the like.
And what we're looking at is how we could treat that runoff so
that when it goes in the ground it's
not going to cause a groundwater contamination problem.
And we're doing work in the field here.
That's a picture of us with our LA partners, taken in August,
and then a picture of now setting up
this trailer in the field, where we're
looking at different combinations of media to help
filter that water.
And the idea then is to see how we can collect and cleanse
the stormwater.
On the water reuse side, we do have systems in place
where the main wastewater treatment plants will produce
water for non-potable use.
That goes into a distinctive colored
pipe called the purple pipe.
And right here for the San Jose Municipal--
San Jose-Santa Clara wastewater treatment plant,
there is this purple pipe system that takes that water back
to different parts of San Jose.
The problem here is that building
that reverse infrastructure is very expensive.
And I'd say we've kind of explored
about the limit of this.
That it's a system that's probably just too
expensive to expand this out anymore than what
we've already done.
The other problems is is that the water is salty
and that you pump that water back uphill.
This is an example of a facility near the Los Angeles airport
that produces recycled water for use by local industry.
And I just wanted to point out that they produce
five flavors of water, not just one kind of water,
but water to make low and high pressure
steam, cooling towers, groundwater recharge,
and for irrigation.
The future here of a lot of this water recycling
is going to be what we would call full advance treatment.
And that's what my class will see this afternoon when
we visit the Silicon Valley Advanced Water Purification
Facility.
But it's taking waste water that's been treated and then
run it through microfiltration and two other steps
of reverse osmosis and UV light.
And that can produce water that's now very high quality.
So this is essentially drinking water quality.
It may not be--
that doesn't mean it will go right into your drinking water
supply.
But it could go into a reservoir or into the ground
and then find its way back to our taps
in sort of an indirect way.
Now the problem with this is that the water
that we have currently available is
from these large main wastewater treatment plants.
And for example, in Los Angeles here, we
have this plant that treats the water for the city
and then this big plant over here
that takes and treats the water for the county itself.
So if you want to do a water reclamation
and put that water around the county,
and if your idea is that well, we're
going to reclaim our water here at the main plant,
then you're left with a picture that looks like this.
And this is what's been proposed by the Metropolitan Water
District.
You would have one great big water recycling plant and then
pumping this water many miles all over the county
and also far uphill and the like.
Well, will this actually happen?
I'm not sure, but that's--
I kind of doubt it.
But there's a different approach rather
than having the one big plant.
You say, well what about decentralized water
reclamation, where you could imagine neighborhood scale
water reclamation facilities.
And a neighborhood might be something that is big--
I should say more like a little village--
big enough that you could capture the water and use it,
and that there would be--
treat it-- and that you could have staff around
to run the facility.
So this is a picture of what we might
do at Stanford, for example.
And we are testing out this idea of decentralized facility,
or decentralized water reclamation
with a facility that's been built over by Serra Street.
Now what this does, it allows us to produce water
for non-potable uses--
irrigation say, flushing, and that kind of thing.
But it saves having to build a five to six
mile pipeline from our water quality control plant.
Also, you don't have to pump water back uphill.
And the water is less salty.
And when we think about water reuse,
the main problem we have really is salts--
salts and viruses.
But salts is a big thing.
And the water down at the main water quality control plant
is too salty for long-term irrigation.
We've built a facility over on Serra Street
to look at new technologies that use advanced
biological and membrane processes to treat
the wastewater in a very compact facility,
capturing their organics as methane that could be
used to help power the plant.
And this is an example of the future
of water reclamation, new technologies, decentralized
systems.
But in order to gain acceptance of this,
we have to test things at scale.
And that's what's being tested over there on Serra Street.
And then lastly about desalination,
if we look at wastewater desalination,
a large plant has just come online in Carlsbad, California.
It's the largest desal plant in the western hemisphere.
But what you're doing here is you're taking seawater, running
it through reverse osmosis--
it takes a lot of energy--
and producing clean water.
But we also do desalination over here
at the Silicon Valley Advanced Water Purification Facility.
There is a desalination step involved
when you treat that water and bring it up to potable levels.
So if you look at the energy intensity
here of what it takes, including the wastewater treatment,
it's about one third of that for the seawater.
So there are good reasons to think about wastewater
reclamation, using new technologies,
and producing a very high quality water.
And that can all be done at a fraction of the energy
costs for desalination.
And then lastly, in order to advance these ideas,
we need to be able to do things at scale.
We need partnerships with utilities who will step out
and say, I will try this, like the Stanford campus saying
we will invest, with an alumni gift develop
a facility to look at how we might
reclaim our wastewater here.
So again, just to summarize then,
what is it that's important here is the decision-making
for new water futures.
We can think about combined water recycling and stormwater
capture, for example.
Storm water use can contribute to our water supplies
but need to be done in a way that will protect groundwater.
Recycling and then energy recovery, we can do it,
but we have to be able to demonstrate things at scale.
And that means we need support for testbeds.
And university alone can't pay for those facilities.
We have to have partnerships.
But it gives us a stepwise approach to change.
Once you can go from a sort of a pilot plant
to the first demonstration plant,
then an idea can take off from there
because it's been derisked.
So that's the message I wanted to get today.
And I thank you for your attention.
[APPLAUSE]
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