(gentle music) (joyful music) - [Narrator] How do you bring
the stream back into balance? How do you restore its biological health? - By using natural stream design were actually assisting the stream to heal itself when it's
sick and not feeling well, restoring some of the
natural biological processes, such as increasing the
number of different kinds of fish that you see in the stream, the number of different kinds of bugs, a sick stream won't have a ton of them, but a healthy stream will. - [Narrator] The more you can mimic nature the more successful you'll be. - The concept we're applying here is very simply applying natural materials, understanding natural processes, letting nature do its
part to protect streams, and managing the energy of the river in a way that works with nature, instead of trying to armor
the banks and resist nature. - [Narrator] Stream
restoration is a process. First, define the
objectives for the stream. Is it flood control? Stream bank stability? Improving access to the stream? Improving habitat? You need to understand what
you hope to accomplish. It is often possible to
achieve multiple objectives with your restoration project. Next, assess the stream. Take a close look at what's going on at that particular site. Is there down cutting or widening, is the stream bank vegetation
healthy and plentiful, has something changed in
the watershed upstream, or is something constricting
the flow downstream? Once you've determined your objective and assess the stream, you have to decide what is your best course of action? In some cases removing local stressors such as cattle grazing,
storm water pipes or culverts and replacing mow turf grasses with native deep-rooted plants may sufficiently improve the quality of the stream channel. However, if you decide that
removing local stressors and revegetation is not enough, then you must work with
qualified professionals and appropriate regulators, such as the U.S. Army Corps of Engineers, to design and later construct
the restored stream channel. No matter which choice
you make you still need to monitor the stream
and maintain it in a form that meets your objectives. Natural stream restoration
includes three parts. Reshaping the channel and floodplain. Building in-stream structures. And, protecting the banks. To begin restoring a stream,
first you have to reshape it. Moving dirt and rocks to establish a more natural stream
channel and floodplain. Reshaping can start with grading banks, creating benches and more gentle slopes. This will reconnect the
stream to its floodplain and help slow the water
during rain events. The redesign of the stream
may mean adding meanders to a straight stream or
creating riffles and pools. For some streams regrading is not enough. Vanes are structures
built into the channel to control the flow
and redirect the water. (upbeat music) This configuration of
rocks or other materials helps lessen the slope of the stream and moves water away from the banks. The first type of vane we'll look at is called a cross vane. So we can utilize our vane technology to keep water in the middle of the channel in areas where both banks are vulnerable, whether we have
infrastructure or other things on the sides of the bank that we don't wanna have erosion at. The cross vane uses our large rocks that are large enough
to not be washed away by the energy of our high flows, and we create a V-structure that's at a 20 to 30 degree angle from the banks, and they are tied into
the banks perpendicular, here underneath ground. You can see these footer boulders that are utilized to
keep the bottom structure of our cross vanes stable. We have our two to five
degree elevation change, here where the waters higher it moves up and moves over back towards the middle, and then as we move to the
upstream end of our cross vane, we have what's called the invert, this is the lowest
elevation of our cross vane, it moves into a pool, this is an area that's deeper, there's
really great habitat and you get a lot of turbulence, a lot of energy dissipation, especially during your high flows. This one is a double step cross vane, so as we move into our second step it allows us once again
to have that turbulence, that energy dissipation,
that great habitat in the second pool, and
then from that second pool it will move up and out into a riffle. (heavy rock music) So another in-stream
structure that's similar to our cross vane, is our J-hook, that once again has two
different functions. It's gonna service grade
control to lower our slope and it's also gonna
help us to deflect water from a vulnerable bank. Our J-hook is utilized to move water away from only one bank, as
opposed to the cross vane that moves water away from two banks. So what we wanna do once
again is we're gonna have our slight slope here
on our vulnerable bank side, and this right here is a log J-hook, it could be also constructed of rocks, it's gonna be tied in up
there at the downstream end of the J-hook, and then tied
in back into the stream bank. So as the water moves
up this vulnerable side it goes up the slope, up the log, and then it's moved back into the center of the stream where it creates this pool. This pool is once again great habitat for lots of little
critters, macro vertebrates, that type of thing. We're installing this with rocks so that we have little areas in between here that the fish and critters can still get upstream during baseflow. This is especially important
in some other parts of the country where you have
critters that go upstream for spawning and that type of thing. And then on the side away
from the critical bank, we have our lower part
of the J that's made of rocks here, and it's
actually tied way back into the bank, all the way to the trees, so that during high
flow, when there's a lot of energy on the bed
and on this point bar, it's not going to get washed away. (heavy rock music) (upbeat music) In larger rivers such as this, a J-hook may not be
practical or even beneficial, because of the large amount
of energy that is involved with this amount of water,
if we install the J-hook in this area we would have the hook part of the J-hook out in the middle of the river where the highest energy is, and the size of boulders
required for that type of installation would be
impractical and very expensive. So instead of that, we
utilize something called a barb, like we have here,
and what the barb does is use the same type of
technology as the J-hook to move the water slightly up slope and dump it back away
from the vulnerable bank and to the middle of the stream, thereby protecting that bank from the high shear stress
that would be involved with the higher flow. (heavy rock music) (upbeat music) So a different type of in-stream structure is known as, toe wood. And toe wood is really
great for stabilizing the outer edge of meander, where you have that vulnerable area where the
stream bottom joins the bank. So what were doing on
this is utilizing logs and sticks and different brush from around this restoration site, that we buried six to
eight feet within the bank, and it provides all these little crevices for the little critters and fish and things like that to live. It also provides structure and things that disrupt the flow at the bottom of the stream, in the deep part of the stream where the most energy is. Over time these sticks are gonna degrade, but we also utilize live plants to create this toe wood, so they are going to sprout and create a treeline along the bottom of our stream bank that will stabilize it over the long-term. (heavy rock music) After reshaping the stream channel there will be a period of time when extra stream bank
protection is needed. Think about bank
protection in three steps. Temporary measures such as matting, that hold the freshly
restored bank in place. Then, some quick, short-term plantings. And finally, the vegetation that's going to be there over the long-term. One of the first things we wanna do on a new stream bank stabilization is to protect the bank from erosion. Here we do that with straw. The straw is going to reduce the impact of the raindrops as it hits the surface, and also as the soil gets wet that straw will incorporate into the
soil and hold it in place. Down here, within the
channel where the water will be flowing, this coir matting, which is made of coconut fiber, helps us to reduce the amount of stress that hits the bank, and holds that soil in place, underneath the matting. The matting will also
give us some structure for vegetation to grow
through as the site matures. - If you have done a stream
bank stabilization project, and you have essentially bare soil banks, the first thing you need to do is put a quick growing grass on those banks to protect it from any water fall, any rain events that come through. Then you need to begin to think about what plants you wanna put into those areas to further stabilize them, to really get the root systems going. Plants that are adapted to
aquatic systems typically have extensive root
systems for that very fact. - That vegetation, over
time, puts in roots that acts as rebar, it
holds soil in place, it helps bind that soil to resist erosion. - [Narrator] You want a
mix of vegetation along the bank, grasses, shrubs and trees. - Things like Bermuda and fescue, which are great for pasture, are not good for stream banks, because they have little short root systems. So what we like to see planted right along the bank are things like big and little bluestem, Indiangrasses. Bluestem can have a root
structure eight feet tall. So it's really going down and
holding all of that in place. - And those roots will help lock that soil and gravel in place so that during future floods the roots are helping hold the soil, and the plants that are growing above ground help slow the water down, taking
away some of the energy that would be causing erosion, leaving most of the flow
energy out in the main channel. - There are plants that
thrive exceptionally well with their feet wet. So we look to put things like willows and other wetland type plants right up at the toe of the stream
so that they can sprout and really vigorously
grow to start holding the soil in place. We're talking about
trees that prefer being in close proximity to
water, that during times of flood when the waters come up, instead of washing out around root holes, the plants themselves will actually bend with the floodwaters, and then when the floodwaters recede
they'll pop back up. - [Narrator] Trees also provide a number of other benefits for a stream, including things you
might not think about. For example, trees cool down the water. Why is that important? - Trees themselves will shade the stream, lowering the water temperature. Many fish species are dependent upon a certain range of
temperatures before they can reproduce, and so it's important that they have those conditions so that you can have a growing population. They also allow for the water
itself told more oxygen, which once again if you
are a fish, or a bug, or as scientist will call
them, macro invertebrates, living inside the stream,
that's important too. You need something to breed. - Leaves also, as they fall into a stream, serve as the very base of the food web. So that we get that carbon input that we need for a healthy ecosystem to support the aquatic insects
in a healthy fisheries. - There are certain aquatic
insects called, shredders, that begin to cut up those
leaves and chew on them and eat them, and then
there are another two or three suites of different insects that will continue to
break those leaves down. - [Narrator] Native plants
can give you a head start on revegetating the banks. - And another key in
selecting those plants is to simply look around and
see what already grows there, in areas up and down that stream. - Those native plants we know are supposed to be here because they're all around us, they will get established
and grow quickly, plus they serve as that
critical wildlife habitat, an important habitat, even leaf quality for streams, for the
insects in the streams and decomposition rates. - [Narrator] Some non-native
plants can be invasive and outcompete the beneficial plants that are vital for a
healthy riparian ecosystem. - What we want to fight against strongly are the invasive exotics
that move in quickly when we have disturbed areas. So managing for native
species and actively trying to remove and slow down the spread of invasive exotics is a critical
element of these projects. - [Narrator] All this work can be done to restore a stream, but it will take the continuing growth of plant life to make it a success. - Plants, above ground and below ground, help serve important processes
for stream restoration. (heavy rock music) - [Narrator] Restoring stream stability and function requires working with qualified professionals
in a multi-step process of assessment, design,
proper construction, and long-term monitoring and maintenance. This design may include,
grading to reconnect the floodplain, in-stream
structures for stabilization, and to decrease the slope
of the stream bottom and lots of vegetation. To achieve success this
type of restoration requires vigilance to
ensure plant establishment, especially during the first
few years after construction. Additionally, these methods
need to be integrated with watershed base plans
and storm water management on the landscape. Major changes to the watershed can impact your stream restoration. By working together we can ensure that the natural beauty and function of our streams can be enjoyed
for generations to come. (delightful music)
