물은 인생을 위한 매우 중요한 요소입니다
농사를 위해, 음식을 위해, 그리고 자연강우를 위해.
어쩔 때는 물은 멀리서 온다
예를 들어, 남부 캘리포니아 물의 절반 이상이
콜로라도 강에서 길어집니다..
그런 다음 위로 운반되고. 그리고 산맥 너머로 길어지고
도시와 농장에서 사용합니다.
하지만 비가 내리면서 그리고 온도가 변하고 있어
과학자들은 대가뭄이
미국 서부 에서 발생한다고 봅니다.
그리고 장기적인 가뭄의 대부분은
콜로라도 강 바로 중앙에 분포하고 있습니다.
LA와 같은 대도시나 시골 농장에
물 공급에 압박이 가해진다는 걸 의미합니다.
이번 에피소드에서는 가뭄이 왜 이렇게 심한지를
그리고 어떤 교훈이 있는지를
남서부의 주민들로부터 수천년 동안
어떻게 이루어졌는지를
알아봅니다. (여기까지)
배수유역은 지역이다.
강수량이 모이는 곳 그리고 특정 수역에 부딪히게 됩니다.
콜로라도 강의 유역
7개 주와 2개 국가에 걸쳐
4천만 명의 사람들이 물을 믿고 있습니다.
하지만 강이 마르면 어떻게 될까요?
그리고 당신이 믿고 있는 물 오지 않는다
To understand, I first asked
water and drought scientist, Brad Udall, what's going on.
In 2000, a drought began that now 20 years later
is the most severe drought
since gauges were installed on the river in 1906 in some places.
The flow is down about 20%.
Drought is usually defined
as a period of abnormally low rainfall
leading to a shortage of water.
But Brad told me that this drought is a bit different.
That's because while rain is down,
that doesn't fully account for the low water levels.
We now actually have a new term for this:
It's a hot drought.
So higher temperatures dry out the earth.
And what we're finding is that higher temperatures
lead to greater evaporation in all its forms.
And that evaporation is the cause of this decline in flow.
In other words, as temperatures increase over time,
the process of evaporation takes more water away
from rivers, lakes, and snow-capped mountains.
This helps explain why river flow in the Colorado basin is down 20%
despite precipitation only being down by 5%.
And droughts do end,
but according to many scientists
waiting for rain in this case is probably not a good idea.
The term "drought" implies
some kind of return to normal at some point.
Drought implies temporary,
and most scientists nowadays have started talking
about the aridification of the West,
meaning a more permanent move to a dry state.
(car engine roaring)
Few people understand the threat of drought
better than Nancy Caywood.
She's a fifth generation farmer in Pinal County
where water either comes from the Colorado River
through the Central Arizona Project canals
or from other rivers and canals in the Colorado basin.
This represents liquid gold.
This is our water supply right here.
We take it out, there's a gate right there,
and it goes down a little lateral canal
that takes it right to our farm.
I'm gonna open up this gate,
we have the gate open,
we'll open four of them, allow the water to flow in.
We have about 135 acres of alfalfa.
This is an example of flood irrigation,
one of the oldest and most common irrigation methods
which distributes water over the soil
by allowing it to flow downhill with gravity.
There's a beautiful simplicity to it,
but it's actually the least efficient way to irrigate
as much of the water either evaporates away
or seeps into the soil out of reach of the plants' roots.
And on top of that, alfalfa is a very thirsty crop,
which means the beef that comes from the cattle it feeds
is the highest water use food commonly available.
Drip and sprinkler irrigation can be much more efficient,
but Nancy told us she's not been able
to get the permits needed
to change the irrigation style on the farm.
And the Caywood alfalfa fields are in good company.
60% of farmland in the Colorado basin
is used to grow feed crops.
Combine all that demand, and here in Pinal County
is where the drought hits home.
The last time the reservoir was full was in 1992.
One year, we had nothing planted on this farm at all.
In 2019 water in Lake Mead,
the nation's largest reservoir, dropped so low
it triggered the first cutbacks
in water allocations ever in the basin.
Pinal County farmers were the first
to have their water reduced.
Fields lay fallow, prepped and ready, but unplanted.
This is a fallow field,
and we just didn't have enough water to plant it.
We have 120 acres of fallow land.
Good news here is, since about 1980
American water use has actually gone down.
Even in growing American cities in the South West,
total consumption has gone down
despite pretty big increases in population.
But worldwide irrigated agriculture
uses upwards of 70% of water in rivers
and municipalities use much, much less, 20% or less.
That's partially due
to household water conservation efforts,
but it's mainly due to the way cities and homes use water.
When you shower, wash dishes or even flush the toilet,
that water is treated and returned to surface or groundwater
rather than evaporating.
The same goes for some industrial uses.
But the largest opportunity and challenge
to reduce water use is in the agricultural sector.
That's because water used for farming
either becomes part of the growing plants
or it's lost to evaporation,
meaning it doesn't return to the hydrologic cycle
for a very long time.
Scientists say this is the worst drought in 1200 years,
but the Hopi you have lived in this area
for over 2000 years and have grown food through it all.
We met up with Max Taylor, a Hopi Water Resources technician
to find out if lessons from one of the oldest communities
in the United States can be applied to modern life
in the drying Colorado basin.
The Hopi's been known to use the least amount of water
than people throughout the whole United States.
It's just because we live in the desert,
here we are more aware of how much you use.
And so the use is very little.
So we're down at my field.
This is my blue corn, they're planted here.
All of these are dry farmed.
I don't do any irrigation.
And the technique we use is you clear off an area.
You'll dig a hole down about maybe eight to 10 inches deep,
get maybe eight or ten kernels of corn
and toss in there.
The wet moisture that you've taken up,
you push them back in,
then you cover it with the dry soil.
And that's dry farming.
His garden is planted in a low lying area
to collect the little moisture that falls each year.
And his crops are extremely adapted to the region.
They're planted far apart to avoid competition for water,
and they grow very deep roots that tap into groundwater.
Right now we're in September.
You can still feel a little bit of moisture in the ground,
see that?
Not much, but just enough that it's still keeping them going.
Amazingly Max uses seeds for his own farming consumption
that produces crops in what seems like dust
with no irrigation.
He's never watered this field.
We have seeds that are being passed on from generation to generation.
So they're adapted to this dry climate.
The corn's been with the Hopi at least several thousand years.
I think the lesson to learn
is that you have to live within your environment.
And I think that's how the natives have survived in these areas
because they were sustainable.
And we know this country.
Shifting towards crops appropriate for
and adapted to their environment
provides a vast opportunity for water conservation.
That shift can happen on farms or in cities
when we choose to eat foods that need less water to grow.
On paper, a shift from feed crops and cattle makes sense.
But if we want to adapt
to our warming climate in an equitable way,
we can't write off farmers like Nancy and the families
that have fed us for generations.
We would like to continue farming.
We don't plan on giving up this farm.
We are looking into alternatives,
we're looking into alternative crops,
we're looking at water conservation irrigation techniques.
Alfalfa takes seven to nine acre feet of water a year to grow it.
Olives would take about one and a half acre feet of water.
But if we were to get into, say, olives,
there'd be a lot of soil preparation.
So it costs us a lot money to get started.
But the question is, can we come together as a country
and implement techniques to reduce the strain
on our water supply before there are even more shortages?
We need to be ready
for some really big changes coming at us
that are frankly outside of our comprehension.
This is how we make the best out of a bad situation
and stand by those
who end up facing the biggest changes and challenges.
And while we focus
on the American Southwest in this episode,
drought does affect almost every part of the country.
So practicing water conservation
as a part of your daily life can help you prepare
for when water supplies run low in your region.
Some of the most effective things you can do today
are not that hard.
For example, never leave a faucet running when it's not being used,
like when brushing your teeth or washing dishes.
Make sure to fix leaky faucets
and choose energy- and water-efficient appliances.
If you want to get more involved,
you can place a brick in the tank of your toilet
so it uses less water for each flush,
or convert your lawn to a beautiful landscape
that doesn't need irrigation.
Or even install a rainwater catchment system.
Of course, there's another thing we can all do,
and that's to fight the underlying cause of this drought, climate change.
The future of this drought is unwritten,
and the less warming we create,
the brighter our water future will be.
So check out the excellent show, Hot Mess,
for more ideas about what can be done.
And of course, subscribe
to keep up with all of our episodes of Weathered.
(soft music)