[MUSIC PLAYING]
[RUNNING WATER]
The mountain streams that we work
in are small headwater streams.
You can roll up your pant legs and walk across.
They're not real big.
But there's a lot going on beneath the surface.
There's a lot going on with the life and the chemistry.
The Shenandoah Watershed Study started in 1979
as a collaborative project between the University
of Virginia and the National Park Service,
and then expanded to streams beyond the park.
35 years ago, we were just beginning
to understand the effects that pollutants
were having on the atmosphere.
By measuring weekly, water chemistry,
and understanding the hydrology of these systems,
we're getting information from the entire watershed.
Sulfuric acid is one of the components of acid rain
that changes the pH of the stream system.
And that change in pH is crucial to facilitating other chemical
reactions, which impact the habitat
quality for the fish and everything that
lives in the stream.
We also bring in students to pose new questions,
collect new data, and also, we're
trying to understand new pollutants
that we hadn't thought about, back 35 years ago.
Mercury is a hazardous material.
It hurts human life.
It hurts other forms of life.
And we're going back hundreds of years.
And we're seeing that as soon as the Industrial Revolution came.
We see this huge increase.
We've made a lot of progress, and we've impacted legislation,
and we have cleaned up the atmosphere
for targeted pollutants.
But we're not back to the natural health
of these systems.
35 Years ago, we didn't know what was going on
in this environment.
We have a much better understanding
of what the impacts are of acid deposition,
and how different streams recover differently,
and why that is.
But it also gives us the understanding to move forward,
to be prepared to answer the next emerging questions.
[MUSIC PLAYING]