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Water in the 21st Century: The National Water Census

Information presented is factual at the time of creation.
If no transcript and/or closed-caption is available, please notify us.
[NOTE: in some cases, the lecture transcripts have been edited for clarity.]

Eric Evenson: Good evening everyone.

Can everybody hear me OK? Great.

Thanks. And I also appreciate you

coming out on such a rainy, and windy,

and cold night to hear about the Water

Census. Just starting out with a little

levity. Dan mentioned that I went to

the University of Nebraska, and grew up in Nebraska.

And of course in Nebraska you know our

saying is, the N stands for knowledge.


OK. I want to talk to you tonight about

a program in the USGS that we call The

National Water Census. And what is a

Water Census? Well, first of all it's

part of our strategic plan. In 2007 we

completed a strategic plan that covers

what you see on the right hand side of

the screen there.

And one of the major themes of that is

a Water Census for the United States,

quantifying, forecasting, and securing

fresh water for our Nation’s


Our objective as part of the Water

Census is to place technical

information and tools into the hands of

stakeholders allowing them to answer

two primary questions about water

availability. Does the nation have

enough fresh water to meet both human

as well as ecological needs?

And will the water be present to meet

the future needs. And when we say

stakeholders we think of that very

broadly. Our stakeholders are the

public. They are also the water

management agencies who struggle with

these questions from a regulatory of

planning basis and the like.

There are also the biological resources

managers and stakeholders. And the non-

governmental agencies organizations

that care about these resources very

deeply. Just to give you a definition

on water availability analysis, what

we're talking about there is the

process of determining the quantity and

timing characteristics of water, which

is of sufficient quality to meet both

human and ecological needs.

That's kind of the core of the analysis that

managers struggle with in determining

do we have enough water? Is it of

adequate quality? Is it there at the

times that we needed in order to satisfy these needs.

I also want to just emphasize that

water availability analysis is part

technical information, but it's also

socioeconomic considerations, legal,

regulatory, and even political

considerations that have to be taken into account.

And at USGS we deal with the technical

information aspect of it. So, at USGS

we don't make determinations of water

availability, we help others make

determinations of water availability

and we do that through providing the

technical information, the technical

basis for those analysis.

You'll hear me talk a little bit about

an initiative called WaterSMART, and

that's kind of a label for us and a

brand. And so, what is WaterSMART? It's

a Department of Interior budget

initiative on water availability and

conservation that is coordinated out of

our Office of the Assistant Secretary

for Water and Science.

That's the Assistant Secretary that's

over both the US Geological Survey and

the Bureau of Reclamation. That

individual is Anne Castle and within

the USGS the main activity that's

associated with the WaterSMART funding

initiative is the National Water Census.

Over the Bureau of Reclamation they

actually have three major activities:

associated with the first are river

basin supply and demand studies that

are designed to dovetail with what

we're doing in the water census.

A program called "Title 16" that

provides funding for communities to do

water reclamation and water reuse. Such

things as building desalination

facilities or advance treatment for

waste water, so that it can be reused as a water supply.

And then they also have their

WaterSMART brands, which are

conservation grants that are given out

to entities to conduct water

conservation activities. And they have

brought goals associated with each of these.

So, one question also that probably

comes up is, 'how did we get to this

point where we're talking about a

national census of water in the

country'. And for those of you who have

been involved is this field for some

time, you may remember back to the

1960s and 70s when there was an entity

called the US Water Resources


And the USGS was a

participating agency in the US Water

Resources Council. The council used to

put out the decadal analysis of water

availability for the country. The last

one of which was put out in 1978. The

council was disbanded as an

organization in 1980.

And since that time there is not been a

comprehensive national assessment of

water availability in over 30 years.

So, we feel that it is really high time

that a program like the water census

gets underway. In 2002 Congress asked

us to produce a national framework so

to speak, a national plan for how we

would approach an assessment of water

availability and use across the


And we produced that and it's published

in our circular 1223. In 2005 directly

associated with the release of the

recommendations in circular 1223

Congress funded a pilot study on water

availability in the Great Lakes.

And some of you might ask, hmm water

availability in the Great Lakes, a

place that's got about one fifth of

available fresh water - flowing fresh

water present there. The chairman of

our appropriations committee who

commissioned these studies was from the Great Lakes Basin.

So, it seemed like a good place to do

the pilot study. Then that study lasted

for five years, and I will be talking

about a number of the products that

came out of the pilot study tonight. In

2007 our strategic plan of our agency

came out with the Water Census as the

one of the major six themes in the


In 2007 also a report came

out of the office of science and

technology policy -- their sub-

committee on water availability and

equality -- and it outlined the roles

of all federal agencies on working on

water availability and identify the

activities in the USGS as promoting -in

terms of promoting the need for a Water Census.

Probably even a significant thing that

has occurred in the last decade on

getting us to where we're at now and

the last year and the Water Census is

the passage of the Secure Water Act.

This happened in 2009. SECURE in this

case is an acronym; it stands for

Science and Engineering to

Comprehensively Understand and

Responsibly Enhance water.

And the acronym is sometimes hard to

remember. Also in 2009 the National

Research Council released a report

called “towards a sustainable and

secure water future.” And that report

also highlighted the need for a

national water census.

And then finally in 2011, the President

included in his budget request to

Congress the WaterSMART initiative to

jumpstart activities both in the USGS

as well as the Bureau of Reclamation.

So, how do we go about accounting for

water availability from a technical

perspective? Well, we use something

called the 'water budget'. And the

water budget is really very similar to

the budget that you all for your

finances at home.

It accounts for all the inputs and the

outputs from a given watershed just the

same as your family budget accounts for

all the inputs and all the deposits and

withdrawals from your account. And it

looks at how much is in storage or how

much reserve you might have in your accounts.

And the types of factors that influence

it. So, just to highlight a couple of

those aspects, the green arrows

represents exchanges with the

atmosphere, precipitation coming into

the watershed, evapotranspiration going

out, the amount of water that's

evaporated or transpired by plants and trees.

The blue arrows represent exchanges of

water within the watershed or between

the surficial system in the ground

water. So, it includes fresh water

inflow and outflow, ground water

surface water interaction, exchanges

between deep ground water systems and

shallow, and the flow through the

ground water system.

And finally the gray arrows represent man's

influence on water availability -- are

withdrawals from ground water and

surface water, and are return of some

of that water back to the land surface

through such things as waste water

return flows, agricultural return

flows, or irrigation.

So, our effort in the Water Census is

to start quantifying each one of these

exchanges. We can write simple or

complex equations that represent each

one of these exchanges in the

environment. And we can look at those

interactions either on very large

scales or very small scales.

Or over long time periods or short time

periods. In our effort in the Water

Census is going to be to look at that

on relatively small scales and short

time periods and aggregate that

information up.

So, let's look at that a little bit.

First of all we want to deliver a

nationwide system that allows users to

access all of this information about

water supply. And when I say the supply

cited the equation, I mean all the

things that bring the water or affect

water on the natural landscape –

precipitation, evapotranspiration,

storage, reservoirs, lakes, ice in

snowfield, surface water flows, ground

water flows -- including things like

recharge rates -- and changes in water

levels of aqua forms.

And we also want to look at all the

factors on what we call the demand side

of the equation. How is water used and

one certainly very important aspect

among those are the ecological water


How much water do we need to lead in

the environment to maintain a healthy

ecosystem. As well as what are the

human uses of water? The withdrawals,

the return flows, how do we

consumptively use water, and what are

our run of the river uses?

So, let's talk a little bit about how

we go about delivering that

information. Well, today you can

download this map of our USGS Website.

If you go to our Water Watch homepage

that's listed right here at the bottom.

You can download the map, and the data

behind this map that gives you

estimated monthly runoff for every “HUC

8,” (and I’ll explain to you what that

is in just a second) For every

watershed at the HUC 8 level,

throughout the entire lower 48 states –

- and in not too long a time we'll be

able to include Hawaii, Alaska, and the

Caribbean Islands in this as well.

[Editor’s note: HUC stands for

“Hydrologic Unite Code” ]

But today you can download this

map and it gives you estimated runoff

for every one of those watersheds

throughout the country. And you could

not only download that for this month,

you can download it historically for

every month back to 1900.

Let's say, that if you're working on

water management issues and you really

need water estimates at a finer scale,

and monthly information isn't good

enough for you, you need daily

information. You might want to have

this in hand. And that's part of what

we're going to do under the Water Census.

So, let's envision that under the Water

Census you were able to download data

on precipitation, runoff, base flow,

evapotranspiration, recharge, changes

in surface water storage, down to a

watershed equivalent to 35 square miles

every 35 square mile watershed across

the country.

And not only on a monthly basis, but

daily information on this of all these

factors that influence the water

budget. That's one of the goals that

we're shooting for under the Water

Census. Now, we'll be talking about the

activities that we have underway to get there.

As well, you want to be able to work

with this information, so we will be

designing and building a Website

interface on similar to the web

interface that we use in our stream

stats program. Some of you may be

familiar with that program where you

would be able to select an area on the

screen, point and click.

Have the system delineate the watershed

above that point. And then generate all

the information about the water

accounting components and deliver that

information to the Website for you.

Then you'd be able to work with online

tools to construct your own water

budget of that area.

And maybe even change some of the

parameters to see what kind of

influence that would have. And then

also, access information about trends

in those water availability parameters

going back 30 years.

That's the system that we're designing.

Now we have to do various things in

order to accomplish these because even

though we run approximately 7700 stream

gauges across the country, that by no

means gives us estimates of flow down

to the scales that we're talking about.

So, one of the things that we're doing

as part of this program is developing

the means of estimating flows at un-

gauged stations across the country. So,

that any place on the landscape you'd

be able to point and click, and get

estimate of the flow, not just flow

characteristics or flow statistics, but

actual daily flow values for that piece

of the landscape.

We're also working on similar efforts

for evapotranspiration. And as I

mentioned evapotranspiration is the

amount of water that evaporates off the

landscape, or is transpired by plants.

And those of you familiar with that I'm

sure you know that in many places

throughout the world,

evapotranspiration accounts to more

than 50% of the rainfall.

So if you think about that: rainfall is

our source of water, it's our source of

fresh water in this country and

throughout the world. And about 50% of

that or more in most places in the

world evaporates off or is transpired

by plants into the atmosphere.

So, this is a very important aspect of

the water budget to be able to

quantify. We're working in two efforts

on evapotranspiration. One is to just

look at as a broad landscape feature,

how much water is evaporated off the

landscape for an entire


But then another aspect of

evapotranspiration is we enhance how

much water evaporates, where we

irrigate agriculture. We're bringing

water in, we're importing it to an

area, we're using it to say, irrigate

crops and grow crops off in an areas

that are arid where the ET rates are

relatively high.

And those plants are transpiring water

off that. We also need to get an

estimate of the amount of ET that's

associated with irrigated cropland

because it's an important part of the

water budget and it's also an important

measure of the consumptive use

associated with the irrigated agriculture.

Another activity that we need to do, to

be able to deliver this information is

we really need to enhance our

understanding throughout the nation of

water use.

And here I'm talking about human water

usage. How much water do we withdraw,

transport, consume, and return to the

environment. And we're going to be

using new methods for estimating water

use across the country.

More use of statistical models like

regression models, you're going to be

developing models of how we can relate

water use, human water use to land use

characteristics. And ultimately what we

want to be able to do is we want to

develop the ability to track the drop

of water that humans use from the point

where it's withdrawn, until it's

ultimately returned to the environment.

So, what are some of the things we need

to do in order to do this? Well, first

I want to just introduce this concept

of what we call ‘conveyance’ and water

use tracking. And envision that this is

a simplistic watershed view here. And

some place within the watershed we pump

water out of the ground and we use it

to integrate cropland, OK?

Now, because we're irrigating that

cropland we're enhancing the amount of

consumptive use. So, that's going to

reduce ground water or surface water

resources as a result of that activity.

We need to be able to quantify that. In

other places we may establish a

community water system and pump that

water up to a piece of landscape where

there's a residential development.

And let's say it's residential

development that's on an un-sewered

land where they're using septic

systems. And that residential piece of

land overlaps a drainage basin.

So, some of that water ultimately gets

to return back through septic system

flow, but the part that's out of the

basin is now a out of basin withdraw to

the flow at that gauging station.

And then we also have the

circumstances where we pump water to

sewered land and the waste water after

it's treated in discharge wholly

without outside of the basin, and

that's a complete deplete of withdrawal to this basin.

So, our water use program in the

country has to be able to characterize

all these kinds of conditions and

account for the human infrastructure

from moving water around. This can get

to be very complex because in this

schematic diagram a water supply

system, you may have a surface water

source and multiple sets of well field

in various parts of the system, that

ultimately distribute water to the

population where they use it. And then

the wastewater will be collected and

discharged in another location. So,

this is the whole idea of being able to

track water through the human

infrastructure. As I mentioned this can

get to be very complex. And this

diagram that's done in the hydrologic

unit code six-digit basin for the upper

Colorado demonstrates just how complex

that can become. Now, just to orient

you over on the right hand side here

would be Rocky Mountain National Park

in the continental divide, OK.

So, the city of Denver is right of over

here. And then this watershed stretches

over to about Grand Junction, Colorado,

so we have all the landscape in

between. And the dots that you see in

the map are the 12,500 irrigation

diversions that occur within the

Colorado River Basin.

Some of those are carrying water outside of the basin to

satisfy irrigation needs. And just

zooming in a little bit on the Vail,

Colorado area you can see the number of

diversions and the complexity that occurs with this.

And as I mentioned, these are just the

irrigation diversions, it doesn't

include water use for other types of

needs. So, what kinds of water use

needs do we include in our analysis?

Well, this bar chart shows the

magnitude of freshwater and salt-water

withdrawals for various human uses

across the country.

And they're in ranked order. 49 percent

of all the withdrawals in this country

are used for thermal electric power

generation. That's a lot of times

surprising to people, but extremely

large volumes of water have to be

withdrawn for thermal electric power


Now once through cooling facilities

much of that water -the vast

majority of it is returned back to the

stream unevaporated - but in the case

of facilities have a cooling tower and

the like, much of the water that's

withdrawn will be evaporated. It

depends largely on the technology that they used.

31 percent of all the water that's

withdrawn in the country is used for

irrigation. And irrigation is the 800-

pound gorilla when it comes to

consumptive use because the vast

majority of that water is either

evaporated or transpired by plants.

So, these two categories alone account

for 80 percent of all the water use in

the United States. 11 percent is used

for public supply, so this is the water

that we used in our homes, plus the

water that's withdrawn and delivered to

industries and commercial

establishments within the service area

those public community systems supply.

And then self-supplied industrial water

accounts for an additional 4 percent.

So, 95 percent of all the water that's

withdrawn in the country are from those

four categories. Then we have four

small categories including self-

supplied domestic, that's -everybody

who has their own individual domestic well.

Livestock which is less than 1 percent,

mining which is about 1 percent, and

aqua culture which is 2 percent. Let me

just go back briefly, we've been

accumulating information on water use

at the USGS for a very long time, since

1950. And every five years we put out a

report called ‘Compilation of Water Use

in the United States.’

And just want to give you a quotation

from the National Research Council

report on the significance that they

see in this data that we produce. And

this is a direct quote.

"This “reports estimated water use in

the United States, have been published

every five years since the 1950s and

are one of the most widely cited

publications of the USGS." So, it's a

very significant activity and effort

that we have and one that we need to

even do a better job on if we are going

to deliver a good Water Census.

Part of what we do with these data is

we are able to look at trends in the

country. And I think this is a very

interesting chart -- kind of

surprising to a lot of people to know

that this line is our population growth

since 1950 through 2005.

And of course population is along over

here on the right axis. On the left

axis are hundreds of billions of

gallons of withdrawal. And you'll

notice that was rising very rapidly

until about 1980.

And then it dropped and leveled off

during that time. So, actually over

this entire period our per capita use

of water has actually decreased since

1980. And this is due to a variety of

factors including regulatory programs

that were put in place, water

conservation activities, industry

cutting back on the amount of water

that they use so that they produce less

waste water that would have to be treated and the like.

I want to go on to another type of

water use -a very important type of

water use that people often don't think

about. It's become much more present in

our thoughts in the last two decades,

but prior to that got little play and a

little accounting in our water availability analysis.

And that was the water needs for

wildlife and habitat. We refer to this

as ‘ecological water science’ or

‘ecological flow science.’

And it's a rapidly developing research area

throughout the world and one that were

very interested here at the USGS. Some

of the things that we want to be able

to provide to the country are

classification system so that we can

classify our water bodies as to their

hydro ecological type.

What type of aquatic environment do our

rivers support? We also want to produce

tools and data that allow managers to

systematically assess ecological

effects of change in the hydrology.

When they alter it, what happens?

Do we still have the same species there

that we did before? How does that

change? And we want to assist users in

developing water alteration flow

alteration ecological response

relationships, which are kind of the

building blocks that people use for

ultimately setting ecological flow

objectives. And again we at USGS don't

set those flow objectives, but states

are very active and interested in this

process today. Along with non-

governmental organizations, like the

Nature Conservancy. OK. Other things

that we have to do in the Water Census,

we need to expand our activities in

assessing groundwater swell in water availability.

What we do throughout the country is we

are systematically analyzing what we

refer to as principle aquifers. These

shaded areas on this colored map

represent the 63 principal aquifers

that account for the vast majority of

ground water usage throughout the country.

And actually the top 30 of those, the

30 principle aquifers if ranked in

water-use order account for 94% of all

the groundwater that's used in the

United States.

So, understanding what

happens in these three-dimensional

systems is an extremely important part

of the Water Census and how that water

is moved to the surface, how it's used,

and how it's disposed off.

So, we need to know things such as

recharge values, groundwater yields,

changes in storage, trends in

groundwater indices and groundwater and

surface water interactions to name a


And we will do that through

strengthening the USGS programs for

studying groundwater availability.

Another issue that we're called to do

as part of the Secure Water Act is,

Congress told us “we would like to know

about the Nation's brackish groundwater resources.”

So, those are all the areas of

groundwater throughout the United

States that are too salty to use

directly either for public supply, or

in many cases even for irrigation or

livestock purposes.

And they're quite widely distributed

throughout the country. Most times

these resources are deep and the color

coding is showing you the depth to

saline water in these various areas.

They tend to be areas that we don't

know a lot about from a water supply perspective.

Most of the people would drill into

these are looking for energy supplies.

They're looking for oil or they're

looking for natural gas and that's

where a lot of the data on this has historically come from.

So, Congress has asked us, we want to

know the locations of the resource, the

hydrologic and water quality

properties, and currently who's using

them. And there are communities they're

using saline groundwater and treating

it for their water supply. But of

course that tends to be a very expensive proposition.

We also of course want to know the

issue about quality, what is water

quality's role in water availability?

How does water quality impairment limit

our access to water?

And it doesn't have to be so bad that

you can't use the water, it just has to

be bad enough to make it more

expensive. And all of a sudden your

influencing decisions that people make

about water availability due to water quality.

So, we want to use the strength of the

USGS water quality programs to

determine the degree to which water

quality impairs water availability.

Define the main compounds that are

important to analyze, relate water use,

relate water quality to water use in

return flows and look at the trends.

The last aspect I'm going to talk about

tonight relative to the Water Census is

we've developed a notion of conducting

focused water availability assessments

in smaller watersheds rather than

tackling the entire Nation at once so

that we can learn certain things about

how to relate some of this information

and integrate it together to give us a

comprehensive picture of water


And so, in basins like the Colorado

River Basin, we've been working with

state, local, and regional stakeholders

to define a set of technical questions

that are important to understand about

these watersheds in order to better

understand water availability.

And then we bring the various programs

that the USGS to bare on answering

those questions and developing a

comprehensive picture. We have three

basins that we're concentrating on

right now. The Apalachicola

Chattahoochee Flint River Basins in the southeast.

It's the last time I'll say it in long

hand, it's the ACF Basin for short. For

those of you who don't know where that

is, that's in the Atlanta area and

south out there. The Colorado River

Basin, and the Delaware in the


And there are some important aspects of

these basins of why they were selected

and what about water availability

stresses makes these basins good areas

to study. In the Delaware, even though

the Delaware River Basin represents .4%

of the land area of the country, it

delivers water to 15 million people, 5%

of the U.S. population.

And a lot of that is because of water

basin withdrawals. It has had two

supreme court decrees dividing up the

water amongst the various parties that

use it. It has abundant endangered

aquatic species that are at risk within

the basin and you may have read

recently with the development of the

Marcellus Natural Gas Shale play.

There are looming issues with regard to

natural gas development in the upper

basin. In the ACF there has been.

I'm sure you remember the Georgia

Florida Alabama water wars, the

competition over the resource in

particular, a tug of war between public

supply and agriculture in the Basin.

Much state litigation that's still

going on today.

In the Colorado, it's got a very fast

growing population within the basin.

Lots of energy development. It's the

backbone of hydropower for the

southwest and we've had declining river

flows over the last 15 years.

So, that is kind of my overview of the

Water Census and our plans. I want to

give you a little picture of the work

that we did in the Great Lakes. And

then we'll open it up for questions.

So, we conducted this pilot study

within the Great Lakes basin, and

that's an aerial photograph of the

basin, of course.

All of the products that you're going

to see are available through our


This study and all of our studies we

feel that it is our obligation both to

look at the national emphasis

associated with it.

But also provide the regional focus of

what kind of information can we deliver

that's relevant and usable to regional

and local managers. And biological

resource managers. We developed methods

that were applicable to the national

level, but we responded to Great Lakes

issues and some of you may know that

there's a Great Lakes Compact that has,

as one of its focuses, water availability.

So, a couple of the products that came

out of that. Well, one thing was that

stakeholders within the basin wanted to

get a much greater current and more

accurate definition of regional

recharge within the basin.

Because much of the water that's used

within this basin does not come from

the lakes themselves, it comes from

ground water resources or small streams

on the landscape where the water is

being delivered.

So, understanding how recharge varies

across the landscape was a very

important factor. Another one with

regard to groundwater, are how are the

groundwater divides within the basin

shifting over time as a result of pumpage.

Now just to orient you on this, of

course here's the Chicago area. This

line here, this dotted line comes very

close into the lake and then back out.

That's the surface water divide for the

basin. The historical groundwater

divides were a little bit further out.

So, water, groundwater on this side was

flowing towards the lakes.

But as a result of a lot of the pumpage

within the Great Lakes basin we've been

pulling those groundwater divides

further to the west. And with that, we

change the flow regime to the lakes. It

was important for us to document that,

and that has become part of the

regulatory considerations that the

Great Lakes Basin uses.

You may have read about some of the

interstate lawsuits that were happening

over the Waukesha area. Another issue

in the Great Lakes is just how had the

natural trends manifest themselves over

the last 50 years.

And interestingly the gold circles are

streamgages where base flow has been

increasing over the last 50 years. And

you'll notice that the vast majority of

the places depicted on this map stream

flows is actually increasing over


Well, that can be associated

with the climate signal. A climate

signal in which more water is

evaporating off the lakes and falling

as precipitation on the landscape. And

this is the issue that we're looking at very carefully.

Stream flows have been showing distinct

increase over that 50-year time in most

parts of the basin. Another issue

that's been very present is lake-level

variability. Some of you may have read

that within the last decade, water

levels in Lake Superior have fallen so

low that oar boats carrying or through

Sue Saint Marie Canal have to go

through partially loaded.

Because there's not enough draft, not

enough hydrologic stage to get those

barges through fully loaded. Likewise,

lake-levels have been dropping in the

Lake Michigan and Lake Heron


So, the stakeholders within

the basin said: 'we'd like to see how

lake-level variability within the last

measured record', and that's this

little part right over here that's the

last 150 years ‘relates to the long

term paleo record.’ So, we put together

a 5,000-year history of lake-level

variability in the Great Lakes Basin.

And you can see that actually in

current time, we're pushing the bottom

of the limit in terms of where lake-

level variability has been since just post the last Ice Age.

Another issue in the Great Lakes that's

very important to them, they manage

based upon consumptive use in the

basin. And if you are going to develop

a new project in the Great Lakes that

has more than 5 million gallons per day

of consumptive use, your project has to

be elevated to all eight Governors and

two provincial Governors in Canada for

review before that project can be

approved. So, a very important

issue was, what are appropriate

consumptive use co-efficients to be use

in the basin? How do theirs compare

with climatically similar areas

throughout the country? And how does

consumptive use vary on a seasonal and

monthly basis?

And so this was part of the products

that we developed in the Great Lakes.

And then of course we put together an

overall water budget for the entire

system. And just a couple of highlights

that come out of that, of course we

assess groundwater as resource, and

groundwater within the Great Lake

system is on the magnitude of adding an

entire another Great Lake.

And of course it's in the tens of

trillions of gallons flowing in the

system. The annual outflow of the Great

Lakes is 1% of the storage. So, the

amount of water that's going out

through the same Saint Lawrence seaway

represents about 1% of all the water

that is stored in the system.

Water-use throughout all the Great

Lakes amounts to about 65,000 cubic

feet per second, a relatively small

amount of that annual outflow. And the

consumptive use is about 3,000 cubic

feet per second. Now that just puts it

in perspective in terms of an entire

watershed the size of the Great Lakes.

Does that mean that water use and

consumptive use are not important?

Absolutely not. Because we not only as

water managers need to look at the

entire system, but how that plays out

within our local watersheds. So, this

is just giving you an overall


As I mentioned our reports

through the Great Lakes study are

available on this Website. This

represents the approximately 15

technical products that were produced

as part of the Great Lake study over

the five-year period. And I invite you

and urge you to go and take a look at

the Great lakes Website and the work

that we've done there.

And I just want to conclude by saying,

again our objective as part of the

Water Census is to place technical

information and tools into the hands of

our stakeholders, stakeholders defined

broadly, so that they can answer the

questions that they're facing about water availability.

Again, my name is Eric Evenson, I'm the

Water Census coordinator. I am located

in beautiful Trenton, New Jersey about

three hours north of here. And there is

my phone number and my Email address.

And I'd be happy to answer any

questions that you have. Thank you.


Title: Water in the 21st Century: The National Water Census


Eric Evenson, coordinator of the National Water Census discuses a new set of water resource challenges brought on by the 21st century. Even in normal water years, water shortages and use conflicts have become commonplace in many areas of the United States — especially competition among crop irrigation, growing cities and communities, and energy production. Over the next 10 years, the USGS plans to conduct a new assessment of water availability and use. This national Water Census will address critical aspects of recent Federal legislation, including the need to establish a national water assessment program.

Location: Reston, VA, USA

Date Taken: 12/1/2011

Length: 43:23

Video Producer: Melanie K. Gade , U.S. Geological Survey

Note: This video has been released into the public domain by the U.S. Geological Survey for use in its entirety. Some videos may contain pieces of copyrighted material. If you wish to use a portion of the video for any purpose, other than for resharing/reposting the video in its entirety, please contact the Video Producer/Videographer listed with this video. Please refer to the USGS Copyright section for how to credit this video.


For more information go to: Public Lecture Series: Science in Action

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