- [host Joe Hanson] This is one of the flattest places on Earth,
46 square miles of salt encrusted desert
as far as the eye can see.
It's also one of the most desolate places.
Not much lives here besides salt-loving bacteria.
So it's the last place you'd expect to hear this.
[motor revving]
[rock music]
With nothing to crash into
and no elevation to slow them down,
racers have been chasing land speed records here
for more than 100 years,
using wacky street cars, handcrafted motorcycles,
and whatever this thing is.
It's also a great place to film people
dragging heavy stuff around
and being kind of pissed off about it.
But over the last 30 years,
the salt that makes this desolate
and daring landscape possible is disappearing.
And scientists are racing to figure out why.
[gentle music]
This is Jalika.
She's a crew chief, or team manager,
for one of the teams that races here.
And this year she brought the team's newest member,
eight month old Sequoia.
- [Jalika] I started bringing her out here now as a baby.
I'm hoping that maybe she would find an interest
in either land speed racing or engineering
or science or something like that.
It was going to be a family affair one way or the other
if we knew that right from the start.
- [Joe] Jalika and her husband, Alp,
got married on the flats
and had one of the racing officials officiate.
- [Alp] The salt, it's perfect
and it brings all these people together.
- [Joe] But like most of the racing community,
they know the landscape is changing.
Every year the Salt Flats Association
paves the salt crystals into a smooth, flat surface,
perfect for speed.
And even though this is a desert,
the salt actually keeps the surface cool.
It's so white it reflects much of the sun's
thermal radiation, keeping the ground cool
and preventing tires from overheating.
And cool tires means fewer blowouts at high speeds.
Racing events in 2014 and 2015 were canceled
because the salt crust was too thin and slushy to drive on.
- [Jalika] We are lucky if we get a quarter of an inch all out.
I don't know that I'm hopeful
that it will stay at this level.
Mainly because of what I've heard from racers
that have been racing since like the 1960s
and what the difference has been since then,
all the way up to here.
It's humongous.
- [Joe] To know why the salt is disappearing,
geologists like Brenda Bowen and Jeremiah Bernau
had to figure out how it got here in the first place.
- [Jeremiah] We like to use the terminology
of flooding, evaporation, desiccation cycles.
Most of the time when we think about a salt flat,
we're like, yeah, it's just a dry, desolate expanse,
but it turns out depending on the year, most of the time,
it could be actually a very large expansive shallow pond.
As that system transitions from pond to salt flat,
as the water evaporates out, all these new crystals
of halite start forming and create a new bright surface
that actually it will sparkle in the morning sunlight.
And I can actually see that crow on our timelapse camera
and just expand outwards.
On daily timescales you can see salt
just popping into existence.
- [Joe] The salt flats are part of a closed basin,
meaning they're completely disconnected from rivers
or streams that could drain them.
All the water that comes in, stays in until it evaporates.
What's left behind are the minerals, primarily rock salt,
but the water that brought the salt in originally
isn't there anymore.
- [Jeremiah] You could see there's these giant ditches
that are pulling groundwater out of the system.
Just to the south there's a large potassium mine,
which is a really important agriculture fertilizer.
- [Joe] The potassium mine pulls 5 billion gallons of groundwater
out of the system every year.
It's an economic boon to the region.
In 2016 alone it brought in $1 billion
to the Utah economy, but the mining relies
on pulling out groundwater from a system
that took millions of years to form.
- [Brenda] These are waters that have been traveling through
the subsurface for 10, you know, up to 10,000, 15,000 years.
So a long time for these waters to accumulate
all these solutes and then discharge at these points.
It took millions of years to form this landscape
and we're altering it in, you know, centuries.
- [Joe] It's tricky to just blame the mine
for the salt's disappearance,
because there are a lot of other factors
that affect the whole landscape.
- [Brenda] In general this whole part of the world
has seen a decrease in groundwater levels,
both with changes in climate and also intense water demand.
- [Joe] And worldwide, saline lake systems
like this one are shrinking.
The Dead Sea in Jordan, Owens Lake in California,
The Aral sea in Kazakhstan, all of them are drying out.
100 miles east of the Bonneville Salt Flats,
the Great Salt Lake is at historic lows.
It's lost 50% of its volume and dropped 11 feet
in the last 10 years.
Historic drought and pressure
from a booming and thirsty population
diverts water into municipal wells
instead of replenishing the Great Salt Lake.
- [Brenda] Yeah, these mudflats that in some cases
have toxic sediments being exposed
and then wind events putting that into the atmosphere
and causing air quality and health issues.
- [Joe] The salt flats still have a protective cap of salt
to prevent air quality issues,
but that will change in the future.
- [Brenda] We need to have more holistic view
of how we're valuing these whole landscapes
and managing water in a way
that you have enough water coming into this system.
- [Joe] But to manage a system, you have to understand it.
Brenda and her team are working on that
and trying to include the community
as much as possible in the research.
So there's a collective definition
of what sustainable management means here.
- [Brenda] Sustainable management is in this situation
where we have all of the different stakeholders
involved in the conversation and we're working towards that.
- [Alp] You have to be responsible otherwise, you know,
the next generations will,
none can experience this beautiful place.
- [Jeremiah] The water used to flow into the salt flats from the south.
And there's an interstate highway.
There's train tracks. There's a mine.
Like the water's not going to flow naturally
into this system anymore.
So how do we live with what we got?
[somber music]
♪