(soothing inspiring music)
- Hello, my name is Jason Vogel
and I am with the Biosystems and Agricultural
Engineering Department at Oklahoma State University.
This is a series of three videos
about natural stream restoration.
The first video is about healthy streams
and what makes them work and what makes them healthy.
The second video is about things that can make
the stream unhealthy.
What can degrade the banks and destroy the habitat.
And the final video is about tools
and methods that we can utilize to restore
the stability of the stream bank
while returning the habitat to the stream.
(uplifting country music)
- [Narrator] This is how most of us experience a stream.
We drive over one and probably never give
it a second thought.
What looks like a peaceful never-changing scene
is actually an aquatic habitat teeming with activity.
- Well streams and creeks and rivers are really
the lifeblood of the community when you think about it.
They're a place where people go to recreate,
to fish, to enjoy nature.
They use them for rafting, they use it for fishing.
And so the quality of the stream and the creek
really improves the overall community quality,
the quality of life.
- [Narrator] Fish are swimming.
Plants are growing.
And water is flowing.
- Streams are very important because they're where
all the water that runs off the landscape come together
and they're flowing downhill and they're providing
habitat, they're providing recreational areas
and they're providing important
ecosystems for our landscape.
But streams are constantly changing.
And what we're trying to do is get
that changed to be in balance where
the amount of soil, sediment, dirt,
other things that are coming into the stream
are equal to what's moving out.
- [Narrator] Balance is our goal.
And now what happens when that balance changes?
A stream might accumulate more sediment.
More solid materials in the water means poor water quality.
Sedimentation is the number one water quality issue
in the United States.
Other areas of the stream could lose more soil,
which can lead to loss of land as stream banks
begin to break down.
- One of the big reasons that people become concerned
about the streams and rivers on their properties
is that there is erosion occurring
on the stream banks, which really impairs
the use of their property for recreation,
for access to the stream.
- [Narrator] So how does a stream fall out of balance?
It happens several ways.
In egg areas, grazing cattle can remove
all the vegetation from the stream banks.
And many times, human influences can affect
the balance of a stream.
Streams adjust to changes in the land such as urbanization,
which occurs when development expands into rural areas.
- So also as a result of urbanization,
excess soil and sediment within the stream
can go downstream and settle out in our downstream
reservoirs that are all used for recreation,
flood control and drinking water.
So all of those uses are compromised.
In addition, we can lose valuable land
across the landscape from our roll areas
and also from our urban areas and compromise
our urban infrastructure.
- [Narrator] When streams become degraded,
they can be restored to a natural balance.
Their functional state can be brought back
using natural stream restoration techniques.
Stream restoration involves controlling
the flow and speed of the water.
- So to help understand how water flows
in the stream, let's think about driving down a road.
On a straight road, you can go faster
because you have no obstacles in your way.
- [Narrator] Just like on a straight road,
the flow of water in a straight stream is very fast.
Again, there's nothing in its way to slow it down.
- But when we're driving on a curvy road,
if we don't slow down, momentum
is gonna take us right off the road
and into the ditch.
- [Narrator] Water is the same way.
The curves or meanders of a stream
slow down the flow.
What about a bumpy road?
You still can't drive fast.
The uneven surface forces you to drive slower.
Now imagine that coarse rough bottom
of the stream, what happens?
The uneven stream bed causes turbulence in the flow.
The water can no longer take a straight path.
An artificially smooth stream bed
is not healthy for the stream or habitat.
There's nothing to slow down the water,
which in turn creates more opportunities
for erosion downstream.
The slope of a stream is also crucial.
- The flow and speed of water are important
because water always flows downhill.
For example, this hill behind me is very steep.
And if I were to drive the truck straight down
the hill without riding the brake,
I would probably lose control and crash.
- [Narrator] Slope is the amount of fall
over the length of the run.
Because the curves or meanders make
the road longer, the slope is lessened.
It's the same idea with a stream.
You add some curves, lessen the slope of the stream bed
and as a result you slow down the flow of the water.
Remember, natural streams are not straight,
they have a meandering flow.
The curves or meanders slow down
the water so velocity is reduced
and the force is not there.
Another way streams control flow
is through their structure.
Streams naturally form riffles and pools.
The riffle is the part of the stream
of the greatest slope and it's very shallow.
At the bottom of the slope is a pool.
It's a large deep area of relatively still water.
This is where fish and plant life thrive within a stream.
Further down the stream this pattern
of riffles and pools will repeat.
The riffles are the areas of the fastest moving water.
Water is moving at a high velocity,
so the sediment and other particles
in the water are on the move.
When water reaches the deeper pools,
the velocity slows which in turn slows down the sediment.
Some of the particles will settle out here.
The process of sediment movement
within the stream is called sediment transport.
- When a stream is healthy that process
will be an equilibrium meaning
that the amount of sediment that's coming down
the stream and depositing will be equal
to the amount that's being moved downstream.
- [Narrator] The balance that we're looking
for in a stream is in sediment transport.
Relatively equal amounts going out and coming in.
A stream is a dynamic system.
Even one that is in balance will change just slowly.
- Generally when we look at healthy natural streams,
they move on the order of a few inches every decade.
Unhealthy and unstable streams move several feet
every year and sometimes the large storm events,
they can dramatically shift and change.
- [Narrator] A healthy stream has a vigorous stream
bank habitat.
There should be a mix of plants which stabilize
the bank and also provide a home and a food source
for life within a stream.
The habitat needs slow-moving water to thrive.
That means a stream with lots of meanders and pools.
- So our meanders are slowing the water down,
but to keep that meandering stream stable,
we need to utilize structures within
the bank that use things such as sticks
and logs and rocks and living plants
and other natural materials.
And while we're doing that we're providing
habitat for the organisms within the stream,
such as macro-invertebrates like insects
and bugs and snails and all the fish community
that lives within the stream.
- So in general a meandering stream
is healthy because it has lots of diversity in bed form.
And it has diversity of habitats for different types
of animals including fish, including
the insects that live in a stream that the fish eat.
Including muscles and other animals
that depend on that flow.
- [Narrator] Slower water encourages the lifecycle
of the animals, insects and plants
that live within the bank habitat.
Coming up next is When Good Streams Go Bad.
We'll take a closer look at what happens
when a stream is no longer in balance.
Part Three in this series will show
the techniques and steps for natural stream restoration.
(uplifting country music)