Site Description
This section provides a description of the physical features, hydrology, climate, and winds, found in the Stillaguamish River GRP planning area and includes an overview of the oil spill risks in the region.
The planning area resides entirely within Snohomish County and includes the city of Arlington. To the northwest the planning area adjoins the Skagit River GRP planning area. The north and south borders are adjacent to the North Central Puget Sound GRP. The eastern boundary of the planning area is well within the river’s floodplain.
The STLGR-GRP planning area covers approximately 89 square miles in the northern part of Snohomish County. The entire Stillaguamish River Basin is approximately 700 square miles, with about 3,100 miles of streams. It is the fifth largest river basin draining into Puget Sound. Locals often shorten Stillaguamish and refer to the river as “The Stilly.”
DEVELOPED AREAS
The cities of Arlington and Marysville are located within the boundaries of this planning area in northern Snohomish County. Smaller communities include Smokey Point, Lakewood, Bryant, and Silvana.
TRIBES OF THE STILLIGUAMISH RIVER PLANNING AREA
The Stillaguamish River GRP planning area is within the usual and accustomed territories of a number of American Indian Tribes. The Indian reservation of the Stillaguamish Tribe of Indians is within the planning area, approximately three miles northeast of Arlington.
The Stillaguamish Tribe of Indians maintains their own Stillaguamish River Geographic Response Plan. The Stillaguamish Tribe should be notified of any spill in the Stillaguamish Basin so that they are able to make decisions and take actions to protect the Tribe’s natural, cultural, and economic resources.
Other federally recognized Tribes with access to the resources of the Stillaguamish River may include the Sauk-Suiattle Indian Tribe, Snoqualmie Tribe, Suquamish Tribe, Swinomish Indian Tribal Community, and Tulalip Tribes.
Tribes can fill many roles during an oil spill response including full participation in Unified Command, providing resource specialists in the Environmental Unit, monitoring on-scene operations, and more. Information regarding tribal participation in a response is available on the Northwest Area Committee/Region 10 Regional Response Team website. Contact information for the tribes in this planning area can be found in the Resources at Risk section and on the Spill Response Contact Sheet of this GRP.
Physical Features
Geology & Landscape
Like other Puget Sound rivers, the physical features of the Stillaguamish River Basin were shaped by tectonic and volcanic activity, glacier meltwater, and human development. In the Stillaguamish planning area, the topography is mostly flat floodplains with some rolling hills.
The Stillaguamish River GRP planning area does not include the river delta or lands adjacent to Puget Sound. The western boundary of the area is more than 4 miles upstream from the mouth of the Stillaguamish River. In the same manor, the eastern side of the planning area does not extend into the mountainous and heavily forested areas of the Cascade foothills.
The Stillaguamish River flows in a westerly direction, although it meanders considerably throughout its broad floodplain. The river has two main forks, the North Fork Stillaguamish coming from the northeast, and the South Fork Stillaguamish coming from the southeast. The forks meet in the city of Arlington, with approximately two miles of each fork included in the planning area.
At least twelve other smaller creeks or sloughs contribute to the flow of the Stillaguamish River within the planning area, including: Armstrong Creek (3.1 Miles), Cook Slough (1.7 Miles), March Creek (2.4 Miles), Pilchuck Creek (9.2 Miles), Portage Creek (10 Miles), and South Slough (1.8 Miles). The creeks with the most river miles in the planning area include Portage Creek with ten miles coming from the south and Pilchuck Creek with 9.2 miles coming from the north.
The predominant use of the land in this area is for agriculture. Farmers in this area grow corn, fruit and vegetables, and raise livestock for meat and dairy. The remainder of the area is taken up by suburban housing developments, especially in the area along I-5 between North Marysville and Arlington.
Interstate-5, western Washington’s major north-south transportation corridor passes through the Stillaguamish River GRP planning area. State Route 9 is also a busy corridor through the east side of the planning area, running in a north-south direction. The other major highways, Washington State Routes 530, 531, and 532, all run in an east-west direction.
Cultural Features
People have inhabited the planning area for thousands of years, living and camping along the Stillaguamish River and its tributaries. Evidence of pre-contact villages and camps may be present along the waterways of the planning area. Today, the Stillaguamish River planning area provides important natural and cultural resources, plants, wildlife, and fish, which are used for commercial, subsistence, and ceremonial purposes.
Shoreline Description
Within the planning area, the Stillaguamish River has a gentle gradient as it flows toward Puget Sound. This section of the river consists of long deep pools that are separated by stretches of shallow riffles. The river bottom varies from sand to gravel with more sedimentation in the slower flowing areas. In the planning area, the riverbanks may be broad, gently sloping gravel bars or steep, earth-cut banks lined with riprap and gravel. Bushes, shrubs, and some blackberries line the river with some stands of taller deciduous trees.
Dams & Irrigation
There is a diversion dam where Cook Slough splits from the main Stillaguamish River channel, just downstream from the Interstate-5 bridge. The Cook Slough Diversion Dam provides gradient control and keeps summer flow adequate in Cook Slough and the main stem Stillaguamish. The weir also provides some fish passage.
Surface water withdrawal devices may be present for agricultural irrigation, industrial activities, or other uses. Consult the Dept. of Ecology Water Rights Search website for more information.
Superfund Sites & Other Historic Pollution Sites
There were no Superfund or other historic pollution sites identified in the Stillaguamish River GRP planning area.
SOCIO-ECONOMIC FEATURES
Large Scale Restoration Sites
There are several habitat restoration efforts happening in the Stillaguamish River watershed restoring and protecting salmon habitat. Restoration efforts focus on creating and protecting riparian habitat, improving floodplain connectivity, and large woody debris placement in channels. Projects include the Lower Pilchuck Creek Wildlife Preserve and the Trafton Floodplain Restoration project on the North Fork.
Fishing & Sustenance
Habitat in the Stillaguamish River planning area supports the natural resources that communities may rely on for sustenance and subsistence, including salmon and resident fish. Due to declining Chinook populations, the Stillaguamish Tribe has only harvested Chinook salmon for cultural purposes since the 1980s. Pink, Chum, and steelhead populations have only been available to tribal members for ceremonial and subsistence opportunities. Coho salmon is the only species in enough abundance to allow for harvest (Stillaguamish Tribe). The Stillaguamish River is closed to sport fishing in the planning area. Check WDFW regulations for more information.
There are three salmon hatcheries in the planning area or upstream of the planning area: Harvey Creek Hatchery and Brenner Creek Hatchery are operated by the Stillaguamish Tribe. WDFW operates the Whitehorse Rearing Ponds on the North Fork Stillaguamish River.
Recreation & Tourism
There are many recreational opportunities involving the waterways in the Stillaguamish River GRP planning area. Throughout the summer people play in the water and float the river on tubes, floaties, and kayaks. In addition, recreational activities include walking, hiking, and picnicking.
Popular river access locations in the planning areas include Twin Rivers Park and Haller Park in Arlington. Upstream of the planning areas, along the South Fork Stillaguamish River, River Meadows Park, Jordon Bridge, and numerous locations on the Mountain Loop Highway in the Mt.
Baker/Snoqualmie National Forest are popular for river users. On the North Fork, the 27-mile Whitehorse Regional Trail follows the former path of the BNSF railway through the North Stillaguamish River Valley to Darrington.
Economic Drivers
The Stillaguamish River’s popularity with recreational users is a significant contributor to the economic health of adjacent communities. Recreational activities enhance the quality of life for residents and attract visitors, driving economic growth through direct spending on equipment and services, lodging, dining, and tourism.
Hydrology
The Stillaguamish Watershed (WRIA 5) includes the mainstem, North and South Forks, and several tributary rivers, streams, and creeks. The Stillaguamish Watershed is in northwestern Washington State. It primarily covers areas in Snohomish County and extends slightly into Skagit County.
The flow of the Stillaguamish River is driven by precipitation and snowmelt. Rainfall is heaviest in the fall and winter which significantly increases streamflow often leading to high flows and flooding. Flow is also high in spring and early summer as snow melts in the Cascade Mountains.
During the dry summer months, groundwater discharges into the river sustaining baseflows. River gage data is available from USGS. River flow data is available from NOAA.
Climate and Winds
Located in western Washinton, the Stillaguamish River GRP planning area has a mild, temperate climate with cool, wet winders and mild, dry summers. Winter low temperatures are typically above freezing, usually in the low 30s. Summer highs usually hit in the low-to-mid 70s. Snow is rare and if there is accumulation it usually only not more than a few inches. Total precipitation averages 47 inches annually (WRCC).
Wind speed at Arlington Airport averages 4.9 mph. From October to February the prevailing wind is south-southeast, in March and April it is from the south, and from May to September the prevailing wind is from the northwest (WRCC).
Tides and Currents
Tidal influences are observed upstream to around river mile 6, where South Slough and the Old Stillaguamish River Channel rejoin. Puget Sound’s tides are mixed semi-diurnal, with two daily high tides and two low tides of varying heights per day. In the lower Stillaguamish, the river’s waterline can move several feet up and down the width of the shoreline over a tidal cycle. Tidal predictions for the Stillaguamish River at Stanwood are available from NOAA.
Risk Assessment
The Stillaguamish River GRP is plentiful in natural, cultural, and economic resources, all at risk of injury from oil spills. Potential oil spill risks include, but are not limited to oils that may sink (non- floating oils), rail transportation, oil pipelines, road systems, aircraft, and other oil spill risks. This section briefly discusses these risks and how they could impact the GRP planning area.
Non-Floating Oils: Both refined petroleum products and crude oils are transported in bulk within this planning area. Crude oil contains a mix of hydrocarbons with a wide range of properties, while a refined product is a single type of oil, such as diesel or gasoline. Depending on the oil and the characteristics of the water the oil is spilled into, some of the oil transported in this planning area may not float.
Different oils will behave differently when spilled to water. Some heavy oils will sink immediately, some oil suspends in the water column, and lighter oils may remain on the surface and evaporate within hours. Over time, oil that initially floats can weather and mix with sediment, causing it to submerge or sink. Non-floating oils pose a specific risk to the environment because they can harm underwater or bottom-dwelling species that would otherwise be unaffected during an oil spill that remained floating on the water’s surface.
Traditional response strategies, including the booming strategies in this GRP, are designed for floating oil. However, there are steps we can take to plan for and respond to a non-floating oil spill. Non-Floating Oil Response Options and Considerations provides an overview of areas where non- floating oil might accumulate if spilled within this planning area, along with information on specific tactics that may be effective during a response. More response options recommended for finding and recovering oil below the water’s surface can be found in the Non-Floating Oil Spill Response Tool (NWACP Section 9412).
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Rail Transportation: Rail companies transport oil via both unit trains and manifest trains in this area. Unit trains include up to four locomotives, buffer cars, and 118 loaded tank cars transporting oil in 714-barrel (29,998 gallon) capacity USDOT-approved tank cars. Manifest trains include up to four locomotives, a mix of non-oil merchandise cars, and one or more 714-barrel (29,998 gallon)
capacity USDOT-approved tank cars carrying refined oil products, such as diesel, lubrication oil, or gasoline. These trains may include emptied tank cars, each with residual quantities of up to 1,800 gallons of crude oil or petroleum products. Every train locomotive typically holds a few hundred gallons of engine lubrication oil, plus saddle tanks that each have an approximate capacity of 5,000 gallons of diesel fuel. Manifest trains may also transport biological oils and non-petroleum chemicals.
Unit trains carrying crude currently operate on specific routes. Unit trains carrying crude from the Bakken Formation in North Dakota enter Washington State near Spokane, continue along the Columbia River to Vancouver, and then head north along I-5. Through the Stillaguamish River planning area, the BNSF line runs northwest from Marysville towards Stanwood, crossing over Cook Slough and the Old Stillaguamish Channel near Silvana.
Oil Pipelines: BP’s Olympic Pipeline is the only refined petroleum pipeline in the planning area. If this pipeline were to leak or rupture, the impact to natural, cultural, and economic resources could be significant.
The 299-mile-long Olympic Pipeline distributes refined products from the northern refineries to most of the terminals and refineries in this area, as well as SeaTac airport, and continues south into Oregon. This pipeline transports refined petroleum products, mainly diesel, gasoline, and jet fuel. In the Stillaguamish River planning area, the Olympic Pipeline runs in a north-south direction near I-5.
Road Systems: Vehicle traffic on roadways pose an oil spill risk in areas where they run adjacent to the shoreline, or cross over lakes, rivers, creeks, and ditches that drain into the Stillaguamish River. Interstate-5 and State Route 9 run in a north-south direction through the planning area and cross over the river at Arlington. A vehicle spill onto one of these bridges or roadways can cause fuel or oil to flow from hardened surfaces into the Stillaguamish River or its tributaries. Commercial trucks can contain hundreds to thousands of gallons of fuel and oil, especially fully loaded tank trucks, and may carry almost any kind of cargo, including hazardous waste or other materials that might injure sensitive resources if spilled. Smaller vehicle accidents pose a risk as well, a risk commensurate to the volume of fuel and oil they carry.
Aircraft: The Arlington Municipal Airport is within the Stillaguamish River planning area. Landing strips at the airport are used for recreational and commercial purposes. With airports in the area, the potential exists for aircraft failures during inbound or outbound flights that could result in a spill with a release of jet fuel to the Stillaguamish River or its tributaries.
Other Spill Risks: Other potential oil spill risks in the area include road run-off during rain events, onshore or near shore construction activities where heavy equipment is being operated, and the migration of spilled oil through soil on lands adjacent to the river or along creeks or stream banks.
Resources at Risk
This section provides a summary of natural, cultural, and economic resources at risk in the planning area, including those resources at risk from oils with the potential to sink or submerge. It provides general information on habitat, fish, and wildlife resources, and locations in the area where sensitive natural resource concerns have been identified. It offers a summary of cultural resources that include fundamental procedures for the discovery of cultural artifacts and human skeletal remains. General information about flight restrictions, wildlife deterrence, and oiled wildlife can be found near the end of this section. A list of economic resources in the area is provided in the appendix.
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This section is purposely broad in scope and should not be considered comprehensive. Some of the sensitive resources described in this section cannot be addressed in Response Strategies and Priorities because it is not possible to conduct effective response activities in these locations. Additional information from private organizations or federal, state, tribal, and local government agencies should also be sought during spills.
This material is presented with enough detail to give general information about the area during the first phase of a spill response. During an actual incident, more information about resources at risk will be available from the Environmental Unit in the Planning Section.
Note: specific resource concerns related to areas that already have designated protection strategies may be found in the “Resources At Risk” column of the matrix describing the individual strategies.
The information provided in this section can be used in:
- Assisting the Environmental Unit (EU) and Operations in developing ad hoc response strategies.
- Providing resource-at-risk “context” to responders, clean-up workers, and others during the initial phase of a spill response in the GRP area.
- Briefing responders and incident command staff that may be unfamiliar with sensitive resource concerns in the GRP area.
- Providing background information for personnel involved in media presentations and public outreach during a spill incident.
- Providing information on benthic and water column species or cultural resources present to assist in planning for oils with the potential to sink or submerge.
Natural Resources at Risk – Summary
This area contains a wide variety of aquatic, riparian, and upland habitats. These habitats support many of Washington’s anadromous salmonid species as well as a complex diversity of other wildlife including mammals, birds, and amphibians. Due to their life histories and/or behaviors, some of these species are unlikely to become directly oiled during a spill incident but may be disturbed by other response operations such as cleanup and reconnaissance. Some of the bird species are resident during the year, but many others seasonally migrate through the area.
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Several the species found in this area have been classified under the Federal Endangered Species Act or by the Washington State Fish and Wildlife commission.
Classification types are:
- Federal Endangered (FE)
- Federal Threatened (FT)
- Federal Candidate (FC)
- State Endangered (SE)
- State Threatened (ST)
- State Sensitive (SS)
Federal and State listed species that may occur within this area include:
Birds:
- common loon [SS]
- marbled murrelet [FT/SE]
- yellow-billed cuckoo [FT/SE]
Mammals:
- None expected to be present
Fish:
- Bull trout [FT]
- Chinook salmon (Puget Sound) [FT]
- green sturgeon [FT]
- steelhead (Puget Sound) [FT]
Amphibians:
- Oregon spotted frog [FT/SE]
Insects
- monarch butterfly [FC]
Critical habitats:
These are the specific areas, occupied by an endangered or threatened species at the time it was listed, that contain the physical or biological features that are essential to the conservation of that species – and that may need special management or protection. Critical habitat may also include areas that were not occupied by the species at the time of listing but are essential to its conservation.
The following species have federally designated critical habitats within this area:
- bull trout
- chinook salmon (Puget Sound)
- steelhead (Puget Sound)
General Resource Concerns
Habitats:
- The river and streams throughout this region provide spawning and rearing habitat for several salmonid species. The associated riparian scrub and woodlands play a crucial role in supporting a large diversity and abundance of songbird species as breeding, migrating, and overwintering habitat.
- Wetlands in this region range from freshwater emergent, freshwater forested, freshwater ponds and lakes. All wetland types support a diverse array of bird, insect and fish and wildlife species.
- Restoration sites are areas where significant efforts have been expended to restore natural functions in a degraded habitat.
- Islands provide important nesting habitat for various bird species, as well as habitat for a variety of mammals. Gravel bars provide spawning habitat for Chinook salmon.
- Brackish sloughs and backwater channels provide feeding and resting areas for waterfowl and herons and are rearing areas for juvenile fish.
- Subtidal/Subsurface Habitats – brackish/freshwater. Shallow intertidal and subsurface habitats occur in this region, extending from the lower river to approximately 2 miles above the confluence of the north and south forks.
- Fine sediments (mud/silt/sand) – Associated with slow/still water flows. May have aquatic vegetation present. Animals associated with these areas may be salmonid and resident fishes; birds (dabbling ducks); semi-aquatic mammals (muskrat, beaver, etc.); shellfish (freshwater clams); amphibians and reptiles (frogs, newts, salamanders, turtles, etc.); insects (caddis flies, mayflies, dragonflies, and stoneflies). Many other animals also utilize these areas for foraging.
- Coarse sediments (gravel/cobble) – Associated with moderate water flow. May have aquatic vegetation present. Animals associated with these areas may be salmonid and resident fishes; birds (dippers, harlequin ducks); semi-aquatic mammals (muskrat, beaver, etc.); shellfish (pearlshell mussels, crayfish); amphibians and reptiles (tailed frogs, torrent salamanders; insects (caddis flies, stoneflies). Many other animals also utilize these areas for foraging.
- Bedrock – Associated with fast water with little or no deposition of loose bed materials. Aquatic vegetation not present. Animals associated with these areas tend to be mostly cold-water (salmonid) fishes, birds (dippers, harlequin ducks), and amphibians (torrent salamanders).
- All Northwest salmonid species are present in this region (including the listed Chinook and coho salmon, bull trout, and steelhead). Spawning occurs throughout the river system. Juvenile salmonids use the lower river and shallow nearshore areas extensively for feeding and rearing.
- In addition to salmonids, several dozen species of freshwater fish exist in the Stillaguamish River basin. These species all provide important contributions to stream ecology.
Wildlife:
- Waterfowl concentrations of various species may be found throughout the region in lowland rivers and streams, lakes and ponds, wetlands, and agricultural fields near water bodies. Concentrations especially prevalent from fall through spring.
- Sensitive nesting species in the region include bald eagles, ducks (including cavity-nesting), and great blue herons.
- Mammals common to the region include deer and various semi-aquatic species such as muskrat, beaver, river otter, etc. throughout the basin. In general, this group is dependent on riverine areas, ponds, tributaries, and riparian forests for den sites and foraging areas.
- Resident and migratory songbirds heavily utilize riparian habitats year-round and are susceptible to response activities in riparian vegetation, as well as oiling or oil ingestion if riparian vegetation and shorelines become contaminated.
Specific Geographic Areas of Concern – Overview
- North Meander Reconnection: Off-channel river and wetland habitat. Rearing and refuge habitat for juvenile salmonids and foraging area for bull trout. Waterfowl including swans.
- Goodwin Lake area: Freshwater lakes and wetland habitat. Wintering waterfowl concentration area for a variety of species including ducks (dabbling and diving), coots, cormorants, and wading birds (herons). Cavity-nesting waterfowl on Ki and Shoecraft Lakes. Public recreation areas.
- Gissberg Twin Lakes Park: Freshwater lakes and wetland habitat. Wintering waterfowl concentration area for a variety of species including ducks (dabbling and diving), coots, cormorants, and wading birds (herons).
- Twin Rivers Park (Arlington): Riparian re-vegetation projects. River, riparian, and wetland habitats. Salmonid presence including bull trout, Chinook, and steelhead.
Specific Geographic Areas of Concern – Maps and Descriptions
Figure 1: Specific geographic areas of concern in the Stillaguamish GRP.
Cultural Resources at Risk – Summary
Culturally significant resources are present within the planning area. Information regarding the type and location of cultural resources is maintained by the Washington Department of Archeology and Historic Preservation (WDAHP). This sensitive information is made available to the Washington Department of Ecology for oil spill preparedness and response planning. The Tribal Historic Preservation Offices (THPOs) or Cultural Resource Departments of local tribes (see Table 6‑1) may also be able to provide information on cultural resources at risk in the area and should be contacted, along with WDAHP, through normal trustee notification processes when significant oil spills, or smaller spills above reportable thresholds, occur in the area.
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During a spill response, after the Unified Command is established, information related to specific archeological concerns will be coordinated through the Environmental Unit. In order to ensure that tactical response strategies do not inadvertently harm culturally sensitive sites, WDAHP should be consulted before disturbing any soil or sediment during a response action, including submerged soils or sediments. WDAHP and/or the Tribal governments may assign a person, or provide a list of professional archeologists that can be contracted, to monitor response activities and cleanup operations for the protection of cultural resources at risk.
Table 6.1: STLGR-GRP Cultural Resource Contacts
| Contact | Phone | |
| Washington Department of Archeology and Historic Preservation (WDAHP) | 360- 586-3080 | Rob.Whitlam@dahp.wa.gov |
| Sauk-Suiattle Indian Tribe, THPO | 360-436-0333 | mporter@sauk-suiattle.com |
| Snoqualmie Indian Tribe | 425-888-6551 | Steve@snoqualmietribe.us |
| Stillaguamish Tribe of Indians, THPO | 425-268-5997 | thpo@stillaguamish.com |
| Suquamish Tribe, THPO | 360-394-8529 | dlewarch@suquamish.nsn.us |
| Swinomish Indian Tribal Community, THPO | 360-466-7352 | jjefferson@swinomish.nsn.us |
| Tulalip Tribes | 425-239-0182 | ryoung@tulaliptribes-nsn.gov |
Discovery of Human Skeletal Remains
Any human remains, burial sites, or burial-related materials that are discovered during a spill response must be treated with respect at all times (photographing human remains is prohibited to all except the appropriate authorities). Refer to National Historic Preservation Act Compliance Guidelines (NWACP Section 9403) during an emergency response.
Procedures for the Discovery of Cultural Resources
If any person monitoring work activities or involved in spill response believes that they have encountered cultural resources, all workers must stop immediately and notify the Unified Command and Cultural Resource Specialist. The area of work stoppage must be adequate to provide for the security, protection, and integrity of the material or artifact(s) discovered.
Prehistoric Cultural Resources (May include, but are not limited to, any of the following items):
- Lithic debitage (stone chips and other tool-making byproducts)
- Flaked or ground stone tools
- Exotic rock, minerals, or quarries
- Concentrations of organically stained sediments, charcoal, or ash
- Fire-modified rock
- Rock alignments or rock structures
- Bone (burned, modified, or in association with other bone, artifacts, or features)
- Shell or shell fragments
- Petroglyphs and pictographs
- Fish weirs, fish traps, and prehistoric watercraft
- Culturally modified trees
- Physical locations or features (traditional cultural properties)
- Submerged villages sites or artifacts
Historic cultural material (May include any of the following items over 50 years old):
- Bottles, or other glass
- Cans
- Ceramics
- Milled wood, brick, concrete, metal, or other building material
- Trash dumps
- Homesteads, building remains
- Logging, mining, or railroad features
- Piers, wharves, docks, bridges, dams, or shipwrecks
- Shipwrecks or other submerged historical objects
Economic Resources at Risk – Summary
Socio-economic sensitive resources are facilities or locations that rely on a body of water to be economically viable. Because of their location, they could be severely impacted if an oil spill were to occur. Economically sensitive resources are separated into three categories: critical infrastructure, water dependent commercial areas, and water dependent recreation areas. The appendix provides a list of economic resources for this GRP area.
General Information
Flight Restriction Zones: The Environmental Unit (Planning Section) may recommend Flight Restriction Zones to minimize disturbance or injury to wildlife during an oil spill. Pilots/operators can decrease the risk of aircraft/bird collisions, prevent the accidental driving of wildlife into oiled areas, and minimize abandonment of nests by keeping a safe distance and altitude from these identified sensitive areas.
The Air Operations Branch (Operations Section) will manage all aircraft operations related to a response and will coordinate the establishment of any Flight Restriction Zones as appropriate. Environmental Unit staff will work with the Air Operations Branch Director to resolve any conflicts that arise between flight activities and sensitive resources.
In addition to restrictions associated with wildlife, Tribal authorities may also request notification when overflights are likely to affect culturally sensitive areas within reservations. See Oil Spill Best Management Practices (NWACP Section 9301) for more information on the use of aircraft and helicopters in open water and shoreline responses
Aquatic Invasive Species: The waters of this region may contain aquatic invasive species (AIS) – species of plants and/or animals that are not native to an area and that can be harmful to an area’s ecosystem. If so, preventative actions may be required to prevent the spread of these species as a result of spill response activities and the Environmental Unit is able to recommend operational techniques and strategies to assist with this issue.