NOAA's Response and Restoration Blog

An inside look at the science of cleaning up and fixing the mess of marine pollution


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Using a NOAA Tool to Evaluate Toxic Doses of Pollution at the Hanford Nuclear Reservation

This is a post by Troy Baker, an environmental scientist in NOAA’s Office of Response and Restoration.

Salmon swimming in a river.

NOAA and partners are examining whether chromium released at Washington’s Hanford Nuclear Reservation has affected Chinook salmon eggs and young fishes in the Columbia River. (Department of Energy)

Chromium, manganese, zinc.

Elements like these may show up in a daily multivitamin, but when found in a certain form and concentration in water and soil, these elements can cause serious problems for fish, birds, and wildlife. As assessors of environmental harm from pollution, we see this scenario being played out at hazardous waste sites around the country.

Take chromium, for example, which is an element found in some multivitamins and also naturally in rocks, plants, soil, and animals (and thus at very low concentrations in meat, eggs, and cheese). At the Hanford Nuclear Reservation in eastern Washington, we are evaluating how historical discharges of chromium resulting from nuclear fuel production may have affected soils, river sediments, groundwater, and surface waters along the Columbia River bordering this property.

Of particular concern is whether discharged chromium affected Chinook salmon eggs and young fishes. Hanford’s nuclear reactors, first constructed as part of the top-secret Manhattan Project during World War II, required huge amounts of river water to keep the reactor’s nuclear core cool, and chromium compounds were added to keep this essential equipment from corroding.

A little bit of chromium in the environment is considered part of a baseline condition, but if animals and plants are exposed to elevated amounts during sensitive periods, such as when very young, they may receive harmful doses.

How Much Is Too Much?

Have you heard the saying, “the dose makes the poison?” I wanted to find out how my evaluation of what chemicals may cause harm to aquatic species at Hanford matches up to toxicity data from one of NOAA’s software tools, the Chemical Aquatic Fate and Effects (CAFE) database.

I already knew that chromium in surface waters at the level of parts per billion (ppb) has the potential to cause harm at Hanford, including to migratory Chinook salmon and steelhead. But what does that concentration look like?

A helpful analogy from the Washington State Department of Ecology shows just how small that concentration is: One part per billion would be one kernel of corn sitting in a 45-foot high, 16-foot diameter silo.

Digging Through Data

Government scientists set standards called “injury thresholds” to indicate the pollution concentrations when harm reliably occurs to a certain species of animal or type of habitat. It’s my job to see if we can trace a particular contaminant such as chromium back to a source at the Hanford Nuclear Reservation and then document whether aquatic species were exposed to that contaminant for a certain area and time period and harmed as a result.

I’m currently working with my colleagues to set injury thresholds for the amount of chromium and other harmful materials in soils, sediments, and surface waters at the Hanford Nuclear Reservation.

What’s different in this case is that we are evaluating what short-term harm might have occurred to fishes and other animals from either historical pollution mixtures or existing contamination in the Columbia River. To do that, we need large amounts of toxicity data for aquatic species presented in an easy-to-digest format. That’s where NOAA’s CAFE database comes in.

Graph from the CAFE database showing the level of toxic effects for chromium exposure to a range of fish and aquatic invertebrates.

Example data output from NOAA’s CAFE database showing aquatic invertebrates as the most sensitive freshwater aquatic organism after exposure to chromium for 48 hours in laboratory tests. One microgram per liter (µg/L) is equivalent to one part per billion. (NOAA)

Using this toxicity database for aquatic species, I was able to generate multiple scenarios for chromium exposure to a range of freshwater fish and invertebrates found in the database. I could compare at what concentration chromium becomes toxic to these species and easily see which life stage, from egg to adult, is most affected after 24, 48, and 96 hours of exposure.

The results from CAFE confirmed that setting an injury threshold for chromium somewhere within the “very highly toxic” range of exposure (less than 100 parts per billion of chromium) would be appropriate to protect a wide range of aquatic invertebrates and fish. With the help of CAFE, I was able to quickly double-check whether there is any scientific reason to lower or raise the injury thresholds I’m discussing with my Hanford colleagues.

More Contamination, More Work Ahead

hanford-h-reactor-cocooned-columbia-river_noaa_1946

View of Cocooned H reactor at Hanford Nuclear Facility from Locke Island, Columbia River, Washington. The reactor operated for 15 years and was one of nine along the river. (NOAA)

My colleagues and I have a lot more environmental assessment work to do at the Hanford Nuclear Reservation. Home to nine former nuclear reactors plus processing facilities, that site is one of the nation’s most complex pollution cases.

Part of my work at NOAA is to collaborate with my agency and tribal colleagues through the Natural Resource Damage Assessment process to understand whether harm occurred and ultimately restore the environment in a way that’s equivalent to the scale of the injuries.

We are concerned about more than 40 contaminants at Hanford, but that shouldn’t be a problem for CAFE. This database holds information on environmental fate and effects for about 40,000 chemicals.

The next version of CAFE, due out in 2016, will be able to display information on longer-term effects of chemicals beyond 96 hours, increasing to 28 days if laboratory test data are available. Having toxicity data available for longer durations will be a huge help to my work as it gets translated into decisions about environmental restoration in the future.

Learn more about our environmental assessment and restoration work at the Hanford Nuclear Reservation.


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After Pollution Strikes, Restoring the Lost Cultural Bond Between Tribes and the Environment

This week, NOAA’s Office of Response and Restoration is looking at the range of values and benefits that coastal areas offer people—including what we stand to lose when oil spills and chemical pollution harm nature and how we work to restore our lost uses of nature afterward. Read all the stories.

A young boy hangs humpback whitefish on a drying rack next to a river.

Restoring the deep cultural ties between native communities and the environment is an important and challenging part of restoration after oil spills and chemical releases. Here, a boy from the Alaska Native village of Shungnak learns to hang dry humpback whitefish. (U.S. Fish and Wildlife Service)

When I’ve heard residents of the Alaskan Arctic speak about the potential impacts of an oil spill, I don’t hear any lines of separation between the oil spill causing injury to the environment and injury to the community.

Their discussions about the potential harm to walrus or seals inevitably include how this will impact the community’s ability to hunt for food, which affects both their food security and traditions. The cultures of these communities are inextricably tied to the land and sea.

So I ask myself, in the wake of an oil spill in the Arctic, how would we begin to restore that bond between the environment and the communities who live there? How can we even begin to make up for the lost hunting trips between grandparents and grandkids that don’t happen because of an oil spill? Furthermore, how could we help restore the lost knowledge that gets passed down between generations during such activities?

We know nothing can truly replace those vital cultural exchanges and activities that don’t occur because of pollution, but we have to try. Thanks to our federal Natural Resource Damage Assessment laws, polluters are made accountable for these lost cultural uses of natural resources, as well as for the harm to affected lands, waters, plants, and animals.

An Alaska Native expert teaches two boys how to cut and prepare pike for drying.

Many ideas for cultural restoration after pollution center around the concept of teaching youth the traditional ways of using natural resources. Here, students from the Alaska Native village of Selawik learn to cut a pike for drying from a local expert. (U.S. Fish and Wildlife Service)

Here are a few examples of our efforts to restore these cultural uses of coastal resources after they’ve been harmed by oil and chemical spills, as well as some ideas for the future.

Community Camps in Alaska

When the M/V Kuroshima ran around on Unalaska Island, Alaska, in November 1997, approximately 39,000 gallons of heavy oil spilled into Summer Bay, Unalaska’s prime recreational beach. As a result of the spill, access to the bay and its beach was closed off or restricted for several months.

In an effort to restore the lost use of their beach, the local Qawalangin Tribe received funding for an outdoor summer recreational camp, which focuses on tribal and cultural projects such as traditional subsistence harvesting techniques for shellfish and activities with Unangan elders in Alaska’s Aleutian Islands. To ensure the safety of local seafoods eaten by the tribe, NOAA also arranged for further chemical analysis of shellfish tissues and educated the community about the results.

Cultural Apprenticeships in New York

Years of aluminum and hydraulic fluid manufacturing released toxic substances such as PCBs into New York’s St. Lawrence River, near the Canadian border. This history of pollution robbed the St. Regis Mohawk Tribe, whose Mohawk name is Akwesasne, of the full ability to practice numerous culturally important activities, such as fishing. Legal settlements with those responsible for the pollution have provided funding for the tribe to implement cultural programs to help make up for those losses.

But first, representatives from the St. Regis Mohawk Tribe conducted oral history research, hosted community outreach meetings, and solicited restoration project ideas from the community. As a result of these efforts, they determined that two main components of restoration [PDF] were necessary: an apprenticeship program and funding for cultural institutions and programs.

The long-term, master-apprentice relationship program focuses on the four areas of traditional cultural practices that were harmed by the release of hazardous contaminants into the St. Lawrence River and surrounding area. This program also promotes and supports the regeneration of practices associated with traditions in these four areas:

  • Water, fishing, and use of the river.
  • „Horticulture and basketmaking.
  • „Medicinal plants and healing.
  • Hunting and trapping.

Hands-on experience and Mohawk language training are also integral parts of the apprenticeship program.

In addition to this program, resources have been provided to a number of existing Akwesasne-based programs that have already begun the work of responding to the cultural harm caused by this contamination. One example is providing opportunities for Akwesasne youth and surrounding communities to receive outdoor educational experience in a natural and safe location for traditional teachings, such as respect for the land and survival skills.

Planning for the Worst and Hoping for the Best in the Arctic

Whales, polar bears, and walrus carved into a bowhead whale jawbone.

We need to work closely with each tribe affected by an oil spill or chemical release to help them achieve the cultural connection with nature affected by pollution. You can see this connection in action at the Iñupiat Heritage Center in Barrow, Alaska, where local artists carve traditional icons into the jawbone of a bowhead whale. (NOAA)

Discussions with Alaskan Arctic communities have yielded similar suggestions of potential forms of cultural restoration after pollution. A 2012 multi-day workshop with communities in Kotzebue, Alaska, generated an initial list of ideas, including:

  • Teaching traditional celebrations (e.g., foot races and dances).
  • Teaching subsistence practices and survival techniques.
  • Supporting science fairs with an environmental restoration focus.
  • Maintaining and transferring hunting knowledge by educating youth on proper whale, seal, and walrus hunting methods.

This last idea is particularly intriguing and would involve preparing a “virtual hunt” curriculum on how to shoot whales so they can be recovered, how to butcher an animal, and sharing the results of the hunt with others.

After working here at NOAA since 2008, I can rattle off plenty of restoration ideas for an oiled beach, or oiled birds. But when it comes to restoring lost cultural uses of the environment, there are no off-the-shelf project ideas.

Each tribe is unique and how one tribe’s members interact with their natural environment may not be the same as another tribe’s. While there may be similar themes we can build upon, such as teaching language and harvesting skills, we need to work closely with each tribe affected by an oil or chemical spill to help them achieve once again what pollution has taken away.


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How Do We Measure What We Lose When an Oil Spill Harms Nature?

This week, NOAA’s Office of Response and Restoration is looking at the range of values and benefits that coastal areas offer people—including what we stand to lose when oil spills and chemical pollution harm nature and how we work to restore our lost uses of nature afterward. Read all the stories.

This is a post by economist Adam Domanski of NOAA’s Office of Response and Restoration.

A beach closed sign on a fence in front of an ocean beach at Coal Point.

When an oil spill closes a beach, economists will count how many trips to the coast were affected by that spill and use information on where those trips were originating to measure the lost value per lost trip. This informs the amount of restoration that needs to make up for those losses. (Used with permission of Chris Leggett)

After oil spills into the ocean, NOAA studies the impacts to animals and plants, but we also make sure to measure the direct impacts to people’s use of nature. This is all part of the Natural Resource Damage Assessment process, which makes up for those impacts.

Humans can value environmental quality just for its existence (think of remote mountains and pristine beaches). In the Natural Resource Damage Assessment process, this “non-use value” is most often compensated for by replacing the natural resources or services that were lost.

Oil and Fun Don’t Mix

However, people can also value the environment because they use it for recreational or cultural purposes. For example, people may be affected if they can’t go fishing, boating, or walking along the beach because of an oil spill.

When oil or another contaminant comes near shore, sometimes people will cancel their planned trip, sometimes they’ll change where they’re going, and other times they’ll still take a trip but will enjoy it less. Trustees of the affected resources, like NOAA, apply different tools to measure these recreational use losses (we’ll talk about cultural losses in an upcoming blog post).

However, people may make one of these changes even if there isn’t any oil present on the beach. Sometimes beaches or fishing areas may be closed because cleanup crews or environmental assessment teams are present. Other times, people may hear about an oil spill in the news and may change their trip based on their reasonable expectation that the oil spill will affect their trip in some way.

Infographic showing three scenarios for how people react to an oil spill: some people stay home from the beach, some people go to a beach farther from the oil spill, and some people go to the same beach but have a less enjoyable experience.

Thanks to the Oil Pollution Act, any one of these changes is an impact than we can quantify in the Natural Resource Damage Assessment process.

Counting How Much Less Fun

Under the Oil Pollution Act, people generally can file legal claims for two types of economic losses related to recreational use due to a spill. Lost revenue to local businesses, such as stores, restaurants, and hotels, is a private loss and is reserved for those businesses to claim. On the other hand, the lost value to the would-be hikers, boaters, anglers, and swimmers is considered a public loss and is the responsibility of trustees, that is, local, state, and federal agencies and tribes acting as stewards of the affected public natural resources.

People walking on a developed portion of white sand beach at the ocean.

Pollution makes for a bad day at the beach, which is why NOAA also measures the impact of oil spills and chemical releases on people’s use of natural resources. (NOAA)

To measure these public damages, trustee economists will count how many trips to the coast were affected by that particular oil spill and use information on where those trips were originating to measure the lost value per lost trip. Together, these two pieces make up the trustee claim for lost recreational use after an oil spill.

To measure lost trips, trustees will often use on-site, telephone, or mail surveys in combination with on-site or aerial counts of people on the coast. Sometimes, we can take advantage of other data sources that already tell us how many people visit the coast, such as existing beach attendance data, parking meter counts, or recreational fishing surveys.

For example, after the 2007 Cosco Busan oil spill in San Francisco Bay, trustees performed on-site counts of people at some beaches, used a telephone survey to estimate the levels of use at others, and relied on the California Recreational Fisheries Survey to estimate trips taken by anglers. This information was combined with weather data in a statistical model to predict the number of people that would have taken trips if the oil spill hadn’t occurred. The assessment estimated that there had been over 1 million lost trips.

The lost value per lost trip is measured using economic models that combine information on where people live and which recreational sites they can choose from. Just like shopping at the grocery store (where you choose from lots of different products at different prices), recreators choose between lots of different access points, each of which has a different “price” (in terms of gas and travel time).

People standing around a pier fishing.

When pollution affects people’s ability to use and enjoy natural resources, such as fishing, we use money from the entity responsible for the pollution to fund projects that will benefit the very same users who were affected. (NOAA)

Using many observations of how many people choose which sites at which prices, economists can measure the recreational demand for each site. When a site is affected by an oil spill, this model can be used to determine the lost value to recreators. For the Cosco Busan oil spill, this approach estimated that the average lost value per lost trip was $18.25 (as measured in 2007 dollars).

The goal of the Natural Resource Damage Assessment process is to compensate the public for the harm caused by a spill. After we calculate the lost value, the trustees aren’t done yet. Using money from the entity responsible for the oil spill, we spend restoration dollars on projects that will benefit the very same users who were affected. A few examples of projects we have built include fishing piers, boat ramps, parks, and artificial reefs.

Survey Says

So, how important are lost recreational use claims to the Natural Resource Damage Assessment process? Here are a few approximate numbers from past oil spill cases:

As you can see, surveying how people use the environment is a critical part of this process. And although taking surveys can be annoying, they often times generate really useful data that economists get super excited about—and from which you can directly benefit. So, the next time you get asked if you want to take a survey, take the opportunity to make an economist happy and say yes.

Learn more about the economics of Natural Resource Damage Assessment and the value of a good day at the beach (video).

adam-domanski_150Adam Domanski is an economist who specializes in non-market valuation with the Assessment and Restoration Division of NOAA’s Office of Response and Restoration. He received his PhD in Economics from North Carolina State University and has worked on numerous oil spill and hazardous waste site cases. In his spare time he enjoys traveling and spending time outside.


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From Kayaking to Carbon Storage, What We Stand to Gain (and Lose) from Our Coasts

This week, NOAA’s Office of Response and Restoration is looking at the range of values and benefits that coastal areas offer people—including what we stand to lose when oil spills and chemical pollution harm nature and how we work to restore our lost uses of nature afterward. Read all the stories.

This is a guest post by Stefanie Simpson of Restore America’s Estuaries.

People sitting in canoes and standing on a shoreline.

When coastal habitats are damaged or destroyed, we lose all of the benefits they provide, such as carbon storage and places to canoe. (NOAA)

Estuaries, bays, inlets, sounds—these unique places where rivers meet the sea can go by many different names depending on which region of the United States you’re in. Whether you’re kayaking through marsh in the Carolinas, hiking through mangrove forest in the Everglades, or fishing in San Francisco Bay, you are experiencing the bounty estuaries provide.

Natural habitats like estuaries offer people an incredible array of benefits, which we value in assorted ways—ecologically, economically, culturally, recreationally, and aesthetically.

Estuaries, where saltwater and freshwater merge, are some of the most productive habitats in the world. Their benefits, also called “ecosystem services,” can be measured in a variety of ways, such as by counting the number of birding or boating trips made there or by measuring the amount of fish or seafood produced.

If you eat seafood, chances are before ending on up your plate, that fish spent at least some of its life in an estuary. Estuaries provide critical habitat for over 75% of our commercial fish catch and 80% of our recreational fish catch. Coastal waters support more than 69 million jobs and generate half the nation’s Gross Domestic Product (GDP) [PDF]. Estuaries also improve water quality by filtering excess nutrients and pollutants and protect the coast from storms and flooding.

Another, perhaps less obvious, benefit of estuaries is that they are also excellent at removing carbon dioxide from the atmosphere and storing it in the ground long-term. In fact, estuary habitats like mangroves, salt marshes, and seagrasses store so much carbon, scientists gave it its own name: blue carbon.

How do we know how much carbon is in an estuary? Scientists can collect soil cores from habitats such as a salt marsh and analyze them in the lab to determine how much carbon is in the soil and how long it’s been there.

But you can also see the difference. Carbon-rich soils are made up of years of accumulated sediment and dead and decaying plant and animal material. These soils are dark, thick, and mucky—much different from the sandy, mineral soils you might find along a beach.

Science continues to improve our understanding of ecosystem services, such as blue carbon, and their value to people. For example, in 2014 a study was conducted in the Snohomish Estuary in Washington’s Puget Sound to find out just how much carbon could be stored by restoring estuaries. The study estimated that full restoration of the Snohomish Estuary (over 9,884 acres) would remove 8.9 million tons of carbon dioxide from the atmosphere—that’s roughly equal to taking 1,760,000 cars off the road for an entire year.

Estuary restoration would not only help to mitigate the effects of climate change but would have a positive cascading effect on other ecosystem services as well, including providing habitat for fish, improving water quality, and preventing erosion.

Healthy estuaries provide us with so many important benefits, yet these habitats are some of the most threatened in the world and are disappearing at alarming rates. In less than 100 years, most of these habitats may be lost, due to human development and the effects of climate change, such as sea-level rise.

When we lose estuaries and other coastal habitats, we lose all of the ecosystem services they provide, including carbon storage. When coastal habitat is drained or destroyed, the carbon stored in the ground is released back into the atmosphere and our coast becomes more vulnerable to storms and flooding. It is estimated that half a billion tons of carbon dioxide are released every year due to coastal and estuary habitat loss.

These benefits can also be compromised when coastal habitats are harmed by oil spills and chemical pollution. People also feel these impacts to nature, whether because an oil spill has closed their favorite beach or chemical dumping has made the fish a tribe relies on unsafe to eat.

Scientists and economists continue to increase our understanding of the many benefits provided by our coastal habitats, and land managers use this information to protect and restore habitats and their numerous services. Stay tuned for more this week as NOAA’s Office of Response and Restoration and Restore America’s Estuaries explore how our use of nature suffers from pollution and why habitat restoration is so important.

Stefanie Simpson.Stefanie Simpson is the Blue Carbon Program Coordinator for Restore America’s Estuaries where she works to promote blue carbon as a tool for coastal restoration and conservation and coordinates the Blue Carbon National Network. Ms. Simpson is also a Returned Peace Corps Volunteer (Philippines 2010-12) and has her Master of Science in Environmental Studies.

The views expressed here reflect those of the author and do not necessarily reflect the official views of the National Oceanic and Atmospheric Administration (NOAA) or the federal government.


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Supporting the Response to a Platform Fire and Oil Spill in Bayou Sorrel, Louisiana

Fire burns in one of several oil tanks on a platform in a bayou.

The Coast Guard, with state and local partners, is responding to an oil production platform fire in Bayou Sorrel, Louisiana, March 15, 2016. One of the tanks reportedly collapsed, releasing an unknown amount of crude oil into a canal. (U.S. Coast Guard)

On the morning of March 15, 2016, the U.S. Coast Guard requested assistance from NOAA‘s Office of Response and Restoration for an oil production platform fire near Berry Lake in Bayou Sorrel, Louisiana.

While crews were working to dismantle the platform, one of the oil storage tanks caught fire. No injuries have been reported. The U.S. Coast Guard is leading the response with state and local agencies.

The platform and one of its storage tanks burned throughout the day on March 15 before the tank partially collapsed, releasing crude oil into a canal. Most of the oil released from the tank continued to burn on the water surface and was consumed.

Responders contained the remaining oil and burn residue in the canal with boom.

Fire-fighting vessel sprays water on an oil tank on a platform in a bayou.

Response crews extinguished the fire on the oil production platform and will continue to monitor the scene in Bayou Sorrel, Louisiana. (U.S. Coast Guard)

A second tank on the platform subsequently caught fire but has been extinguished. The two storage tanks had a maximum capacity of more than 33,000 gallons of crude oil.

We are assisting the Coast Guard’s response by coordinating local weather forecast support, modeling the potential trajectory of spills of oil or burn residue, and outlining the wildlife and habitats that could be at risk in the area. A NOAA Scientific Support Coordinator has reported to the response to provide further help and assess potential impacts of the oil spill.

Bayou Sorrel is predominantly composed of seasonally flooded, forested wetlands with some patches of freshwater marshes and open canals. While oil is unlikely to penetrate flooded or water-saturated soils, it will readily coat and become mixed with floating debris such as branches and leaves.

A variety of birds, particularly diving and wading birds and waterfowl, may be present in the area and might be at risk of coming into contact with oil, which can coat their feathers, be ingested, or inhaled. In addition, fish and invertebrates such as crawfish may be present or spawning in the marshy habitats surrounding the oil platform, and alligators and small-to-medium-sized mammals including mink and river otters may be nearby.

In 2013, NOAA provided on-site technical support for an oil spill from a pipeline in Bayou Sorrel and helped coordinate a controlled burn of the spilled oil in the area’s flooded, wooded swamps. Additionally, we assisted with other oil spills in this area in 2015, 2007, and 1988.

Look for more information about the current oil spill and fire here and at the U.S. Coast Guard’s media site.


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NOAA Scientist Helps Make Mapping Vital Seagrass Habitat Easier and More Accurate

Shoal grass seagrass on a sandy ocean floor.

Seagrass beds serve as important habitat for a variety of marine life, and understanding their growth patterns better can help fisheries management and restoration efforts. (NOAA)

Amy Uhrin was sensing a challenge ahead of her. As a NOAA scientist working on her PhD, she was studying the way seagrasses grow in different patterns along the coast, and she knew that these underwater plants don’t always create lush, unbroken lawns beneath the water’s surface.

Where she was working, off the North Carolina coast near the Outer Banks, things like the churning motion of waves and the speed of tides can cause seagrass beds to grow in patchy formations. Clusters of bigger patches of seagrass here, some clusters of smaller patches over there. Round patches here, elongated patches over there.

Uhrin wanted to be able to look at aerial images showing large swaths of seagrass habitat and measure how much was actually seagrass, rather than bare sand on the bottom of the estuary. Unfortunately, traditional methods for doing this were tedious and tended to produce rather rough estimates. These involved viewing high-resolution aerial photographs, taken from fixed-wing planes, on a computer monitor and having a person digitally draw lines around the approximate edges of seagrass beds.

While that can be fairly accurate for continuous seagrass beds, it becomes more problematic for areas with lots of small patches of seagrass included inside a single boundary. For the patchy seagrass beds Uhrin was interested in, these visual methods tended to overestimate the actual area of seagrass by 70% to more than 1,500%. There had to be a better way.

Seeing the Light

Patches of seagrass beds of different sizes visible from the air.

Due to local environmental conditions, some coastal areas are more likely to produce patchy patterns in seagrass, rather than large beds with continuous cover. (NOAA)

At the time, Uhrin was taking a class on remote sensing technology, which uses airborne—or, in the case of satellites, space-borne—sensors to gather information about the Earth’s surface (including information about oil spills). She knew that the imagery gathered from satellites (i.e. Landsat) is usually not at a fine enough resolution to view the details of the seagrass beds she was studying. Each pixel on Landsat images is 30 meters by 30 meters, while the aerial photography gathered from low-flying planes often delivered resolution of less than a meter (a little over three feet).

Uhrin wondered if she could apply to the aerial photographs some of the semi-automated classification tools from imagery visualization and analysis programs which are typically used with satellite imagery. She decided to give it a try.

First, she obtained aerial photographs taken of six sites in the shallow coastal waters of North Carolina’s Albemarle-Pamlico Estuary System. Using a GIS program, she drew boundaries (called “polygons”) around groups of seagrass patches to the best of her ability but in the usual fashion, which includes a lot of unvegetated seabed interspersed among seagrass patches.

Six aerial photographs of seagrass habitat off the North Carolina coast, with yellow boundary lines drawn around general areas of seagrass habitat.

Aerial photographs show varying patterns of seagrass growth at six study sites off the North Carolina coast. The yellow line shows the digitally drawn boundaries around seagrass and how much of that area is unvegetated for patchy seagrass habitat. (North Carolina Department of Transportation)

Next, Uhrin isolated those polygons of seagrass beds and deleted everything else in each image except the polygon. This created a smaller, easier-to-scan area for the imagery visualization program to analyze. Then, she “trained” the program to recognize what was seagrass vs. sand, based on spectral information available in the aerial photographs.

Though limited compared to what is available from satellite sensors, aerial photographs contain red, blue, and green wavelengths of light in the visible spectrum. Because plants absorb red and blue light and reflect green light (giving them their characteristic green appearance), Uhrin could train the computer program to classify as seagrass the patches where green light was reflected.

Classify in the Sky

Amy Uhrin stands in shallow water documenting data about seagrass inside a square frame of PVC pipe.

NOAA scientist Amy Uhrin found a more accurate and efficient approach to measuring how much area was actually seagrass, rather than bare sand, in aerial images of coastal North Carolina. (NOAA)

To Uhrin’s excitement, the technique worked well, allowing her to accurately identify and map smaller patches of seagrass and export those maps to another computer program where she could precisely measure the distance between patches and determine the size, number, and orientation of seagrass patches in a given area.

“This now allows you to calculate how much of the polygon is actually seagrass vegetation,” said Uhrin, “which is good for fisheries management.” The young of many commercially important species, such as blue crabs, clams, and flounder, live in seagrass beds and actively use the plants. Young scallops, for example, cling to the blades of seagrass before sliding off and burrowing into the sediment as adults.

In addition, being able to better characterize the patterns of seagrass habitat could come in handy during coastal restoration planning and assessment. Due to local environmental conditions, some areas are more likely to produce patchy patterns in seagrass. As a result, efforts to restore seagrass habitat should aim for restoring not just cover but also the original spatial arrangement of the beds.

And, as Uhrin noted, having this information can “help address seagrass resilience in future climate change scenarios and altered hurricane regimes, as patchy seagrass areas are known to be more susceptible to storms than continuous meadows.”

The results of this study, which was done in concert with a colleague at the University of Wisconsin-Madison, have been published in the journal Estuarine, Coastal and Shelf Science.


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What Are Our Options for Restoring Lands Around Washington’s Hanford Nuclear Reservation?

Shrub-covered plains next to the Columbia River and bluffs beyond.

The dry shrub-steppe habitat at Washington’s Hanford Nuclear Reservation is rare for the region because it is so extensive, intact, and relatively healthy. (Department of Energy)

Many people might be inclined to write off the wide, dry plains stretching around the Hanford Nuclear Reservation as lost lands. After all, this area in eastern Washington was central to the top-secret Manhattan Project, where plutonium was produced for nuclear bombs used against Japan near the end of World War II. In addition, nuclear production continued at Hanford throughout the Cold War, ending in 1987.

This history left an undeniable legacy of pollution, which is still being studied and addressed today.

Yet this land and the Columbia River that curves in and around it are far from being irredeemable. The Hanford site encompasses 586 square miles. Yes, some parts of Hanford have been degraded by development from its nine (now decommissioned) nuclear reactors and associated processing plants and from chemical and radionuclide contamination.

But the site also includes vast, continuous tracts of healthy arid lands that are rare in a modern reality where little of nature remains untouched by humans.

Where We Are and Where We’re Going

This potential is precisely what encourages Christina Galitsky, who recently joined NOAA’s Office of Response and Restoration to work on the Hanford case. Currently, she is leading a study at Hanford as part of a collaborative effort known as a Natural Resource Damage Assessment, a process which is seeking to assess and make up for the years of environmental impacts at the nuclear site.

“The purpose of our study is to begin to understand habitat restoration options for Hanford,” Galitsky explained. “We are starting with terrestrial habitats and will later move to the aquatic environment.”

A worker drains a pipe that contains liquid chromium next to a nuclear reactor.

From the 1940s to 1980s, the Hanford site was used to produce plutonium in nuclear weapons, and which today is home to the largest environmental cleanup in the United States. Here, a cleanup worker deals with chromium pollution near one of the decommissioned nuclear reactors. (Department of Energy)

NOAA is involved with eight other federal, state, and tribal organizations that make up the Hanford Natural Resource Trustee Council, which was chartered to address natural resources impacted by past and ongoing releases of hazardous substances on the Hanford Nuclear Reservation.

The study, begun in the summer of 2015, will be crucial for helping to inform not only restoration approaches but also the magnitude of the environmental injury assessment.

“We want to understand what habitat conditions we have at Hanford now,” Galitsky said, “what restoration has been done in similar dry-climate, shrub-steppe habitats elsewhere and at Hanford; what restoration techniques would be most successful and least costly over the long term; and how to best monitor and adapt our approaches over time to ensure maximum ecological benefit far into the future.”

The Hanford site is dominated by shrub-steppe habitat. Shrub-steppe is characterized by shrubs, such as big sagebrush, grasses, and other plants that manage to survive with extremely little rainfall. The larger Hanford site, comprised of the Hanford Reach National Monument and the central area where nuclear production occurred, contains the largest blocks of relatively intact shrub-steppe habitat that remain in the Columbia River Basin.

More Work Ahead

Roads and facilities of Hanford next to the Columbia River with bluffs and hills beyond.

The Hanford site, which the Columbia River passes through, encompasses 586 square miles of sweeping plains alongside an atomic legacy. (Department of Energy)

Galitsky’s team includes experts from NOAA, the Washington Department of Fish and Wildlife, and other trustees involved in the damage assessment. For this study, they are reviewing reports, visiting reference and restoration sites in the field, creating maps, and organizing the information into a database to access and analyze it more effectively.

They presented their preliminary results to the trustee council in November. So far, they are finding that limited restoration has been done at Hanford, and, as is fairly common, long-term data tracking the success of those efforts are even more limited. Over the next six months, they will expand their research to restoration of similar shrub-steppe habitats elsewhere in the Columbia Basin and beyond.

Thanks to additional funding that stretches into 2017, the team will begin a second phase of the study later this year. Plans for this phase include recommending restoration and long-term habitat management approaches for the trustee council’s restoration plan and examining the benefits and drawbacks of conducting shrub-steppe restoration both on and off the Hanford site.

Steppe up to the Challenge

Two American White Pelicans fly over the Columbia River and Hanford's shrubby grasslands.

A surprising diversity of plants and animals, such as these American White Pelicans, can be found in the lands and waters of Hanford. (NOAA)

The natural areas around Hanford show exceptional diversity in a relatively small area. More than 250 bird species, 700 plant species, 2,000 insect species, and myriad reptiles, amphibians, and mammals inhabit the site. In addition, its lands are or have been home to many rare, threatened, and sensitive plants, birds, reptiles, and mammals, such as the Pygmy rabbit

Furthermore, the shrub-steppe habitat at Hanford holds special significance because this habitat is so rare in the Columbia Basin. Elsewhere in the region, urban and agricultural development, invasive species, and altered fire regimes continue to threaten what remains of it. As Galitsky points out, “At Hanford there is an opportunity to restore areas of degraded shrub-steppe habitat and protect these unique resources for generations.”

Restoring habitats on or near the Hanford site may create benefits not only on a local level but also more broadly on a landscape scale. These efforts have the potential to increase the connectivity of the landscape, creating corridors for wildlife and plants across the larger Columbia River Basin. The team will be evaluating these potential landscape-scale effects in the second phase of this project. Stay tuned.

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