Lake Chelan GRP
- Interim update: N/A
- Last full updated: 2023
- Public Comment: GRPs@ecy.wa.gov
Table of Contents
This section provides a description of the area’s geography, hydrology, and climate, and includes an overview of oil spill risks in the Lake Chelan area. The plan covers Lake Chelan between Stehekin and the City of Chelan.
Lake Chelan is both the deepest and largest natural lake in the state, and the third deepest lake in the country. Over fifty miles long but averaging just one mile wide, it cuts northwest to southeast at a roughly forty-five-degree angle across the land. At the northwestern top of the lake is the Stehekin River, which provides almost 70 percent of the annual water to the lake. The rest of the inflow is provided by small creeks and streams draining the surrounding Cascade Range and Chelan Mountains.
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The majority of the land surrounding the lake is federally owned natural area. The Lake Chelan National Recreation Area covers the northern watershed and the northern five miles of the lake, down to the border of the Okanogan-Wenatchee National Forest. Within the Forest include the sub-areas of the Lake Chelan Sawtooth Wilderness on the east and the Glacier Peak Wilderness to the west. The Chelan Ranger District controls the central portion of the lake. The southern seven miles of the lake contain the vast majority of the residents and developed areas.
The largest population center is the city of Chelan, population 4000, which wraps around the southeastern point of the lake. There, the lake drains to the Chelan River, passing through town to the Lake Chelan Dam before emptying into the Columbia River. The only other developed areas along the lake are an unincorporated suburb of Chelan called Manson, population 1500, and the community of Stehekin at the northeastern tip of the lake. Stehekin is only accessible by ferry, boat, seaplane, or by foot over Cascade Pass. Two ferry companies operate year-round—the Stehekin Ferry Company and the Lady of the Lake . While Stehekin Airport is open July through September, it is considered a difficult landing spot and is sometimes commandeered for wildland fire response. Stehekin is a popular spot for tourists and private boaters during the summer. The Lake Chelan National Recreation Area sees between 35,000 and 45,000 annual visitors.
Lucerne Landing is a ferry stop located about seven miles south of Stehekin, on the west shore of the lake. Eleven miles west of the landing is Holden Village, a Lutheran retreat center that hosts 6,000 visitors annually and houses around 100 year-round residents. Next to Holden Village is the decommissioned Holden Mine, which produced copper, zinc, gold and silver between 1930 and 1957 before closing. It is currently undergoing remediation and monitoring as a Superfund site, which requires diesel fuel to be transferred by barge twice a year. Visitors and supplies can only arrive via boat or seaplane to the dock at Lucerne Landing, and are then driven on a gravel forest road that parallels Railroad Creek up to Holden Village and the mine.
Table 2-1: Lake Specific Information
Lake levels at Lake Chelan fluctuate depending on time of year, making water access points and some boat launches challenging in the low water season (October-April). Officially known as the Chelan Hydroelectric Project, the Chelan Dam was built in 1928 and is located less than a mile from the river’s mouth. It is a steel-reinforced concrete gravity dam, 40 feet high and 490 feet long. Chelan County Public Utility District Number 1 controls the dam outflows and maintains the water level in the lake.
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The flow into the lake from the Stehekin River, Railroad Creek and other tributaries is largely determined by snowmelt, rather than direct runoff from rainfall. The water level in the lake is lowest in early spring, before the snow has melted. Snowmelt in April and May leads to peak water levels from June through September, remaining steady around 1098 feet. The Chelan County Public Utility District’s license encourages the lake level to stay between 1100 feet and 1079 feet elevation but maintaining ideal flow to the Chelan River takes precedence. The output through the Chelan Dam is generally steady throughout the year.
Climate and Winds
Lake Chelan’s climate is similar to the rest of eastern Washington, with near-desert levels of precipitation. The annual average precipitation at Lake Chelan is 11.4 inches. Rainfall is fairly evenly distributed throughout the year, but in mid-summer it is not unusual for a month or six weeks to pass without any measurable rainfall. The wettest month is November, with an average rainfall of 1.77 inches. Summer high temperatures tend to be in the 80’s and winter lows tend to be in the 30’s.
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Winds on Lake Chelan are strong from April through July, particularly in the upper part of the lake between Stehekin and Lucerne. Sustained winds over 20 miles per hour (mph) are common, with gusts near 40 mph. Stronger winds are unusual but gusts of over 80 mph have occurred.
Wind direction is usually “down lake” (from NW to SE) in late spring to early summer, but direction and speed can vary significantly throughout the day. The rest of the year winds are calmer and more varied in direction. Winds are lower in the lower section of the lake, near Manson and Chelan, but follow the same seasonal pattern.
Tides and Currents
Lake Chelan has no discernible tides or currents. The flow from the tributaries to the Chelan River is generally north-to-south, but the rate at which the lake empties is so low that it should have no major impact on the movement of oil. Wind direction and speed will be the most significant factor in the direction of travel.
Of the few oil spill risks in this planning area, the fuel transport operations supporting the Holden Mine Superfund Site is likely the most significant. During a three-week period every spring and fall, Mountain Barge Services operates a 120-foot barge and 25-foot tug from Chelan to Lucerne Landing, where fuel trucks drive off the barge and follow Forest Service Road 8031 for 11 miles along Railroad Creek. During this time, 3-4 trucks carrying up to 4,600 gallons of diesel fuel each, are transported by barge to support cleanup operations the Superfund site. The largest fuel storage tank at the cleanup site holds 10,000 gallons of diesel, with another two 5,000-gallon tanks nearby. Both tanks are adjacent to Railroad Creek, which flows into Lake Chelan Vehicles and construction equipment at the mine hold under 100 gallons of diesel each.
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Rio Tinto mining is responsible for the Holden Mine Superfund Site cleanup project and their Spill Prevention, Control, and Countermeasure plan has been approved by applicable state and federal agencies. Mountain Barge Services, who operate the tug, also maintain spill response equipment at their headquarters in Chelan. There is a trailer of spill response equipment that can be transported on the barge or stationed in Chelan or Lucerne. There is an additional spill response trailer located in Stehekin.
Barges also deliver gasoline and diesel to the residents of Stehekin and their local marina. This fuel is delivered sporadically by barge though out the year via fuel trucks carrying up to 4,600 gallons This is the most significant spill risk in the northern part of the lake past Lucerne Landing. Small passenger ferries and recreational boating is common in the area, especially during the summer months, spills from these craft are possible.
Vehicle traffic on roadways pose an oil spill risk in areas where they run adjacent to the shoreline, or cross over rivers, creeks, and ditches that drain into Lake Chelan. The bridges at West Woodin Avenue and Webster Avenue/Highway 97 span the Chelan River, where road-based spills would flow south towards the dam. Highway 97, Highway 150 and Highway 971/Lakeshore Road all parallel the southeastern five to ten miles of lakeshore and pose a potential threat from tanker truck accidents.
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.
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 resident fish species as well as a 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 response operations such as cleanup and reconnaissance. Some of the bird species are resident during the year while others seasonally migrate through the area.
- 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:
- common loon [SS]
- northern spotted owl [FT/SE]
- sandhill crane [SE]
- yellow-billed cuckoo [FT/SE]
- Canada lynx [FT/SE]
- fisher [SE]
- gray wolf [SE]
- western gray squirrel [ST]
- wolverine [FC]
- bull trout [FT]
- pygmy whitefish [SS]
- Ute ladies’ tresses [FT]
- Sierra cliffbrake [SS]
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 federally designated critical habitats are present within this area:
- Canada lynx [FT/SE]
- Northern spotted owl [FT/SE]
General Resource Concerns
- Wetlands are present within this region. All wetland types support a diverse array of amphibian, bird, insect, fish, and wildlife species.
- Riparian areas serve as transitional zones between the uplands and the open water of lakes, streams, and rivers. They are heavily used by a variety of wildlife and help to support a diversity and abundance of songbird species as breeding, migrating, and overwintering habitat.
- Stream mouths are concentration areas for fish and feeding areas for a variety of birds.
- Subsurface Habitats – freshwater: Shallow subsurface habitats occur throughout this region.
- 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).
- Resident fish present year-round in lake and streams include landlocked kokanee and chinook salmon, trout (bull, cutthroat, and rainbow), largemouth bass, crappie, and perch.
- Mammals in the area include mule deer (winter range), wolverine, mountain goat, big horn sheep, lynx, and western gray squirrel. Other small mammals common to the region include beaver, muskrat, river otter, mink, and raccoon.
- Raptors that can be found around the area include northern goshawk (breeding area), flammulated owl, and golden eagle (breeding area).
- Resident and migratory songbirds heavily utilize riparian habitats year-round and are susceptible to oiling if riparian vegetation and shorelines become contaminated.
- Amphibians in the area include the western toad.
Specific Geographic Areas of Concern – Overview
- Manson lakes (Wapato, Dry, and Roses lakes) wetlands. These areas, close to the northern shoreline of Lake Chelan, provide foraging and nesting habitat for migrating waterfowl.
- Twenty-five Mile Creek State Park. Wetland and riparian habitat. Rainbow and westslope cutthroat trout, kokanee salmon. Northern spotted owl presence.
- Domke Lake. Wetland habitats. Northern spotted owls and norther goshawk breeding area. Trout and other resident fish.
- Mouth of the Stehekin River. River sustains populations of various resident fish, including trout (bull, rainbow, eastern brook, and west slope cutthroat), kokanee and resident chinook salmon, mountain, and pygmy whitefish.
Specific Geographic Areas of Concern – Maps and Descriptions
Figure 1: Geographic areas of concern in the Lake Chelan geographic response plan.
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 below) 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.
|Washington Department of Archaeology and Historic Preservation
|Confederated Tribes of the Colville Reservation
|Confederated Tribes and Bands of the Yakama Nation
Discovery of Human Skeletal Remains
The finding of human skeletal remains will be reported to the county medical examiner/coroner and local law enforcement in the most expeditious manner possible. The remains will not be touched, moved, or further disturbed. The county medical examiner/coroner will assume jurisdiction over the human skeletal remains and make a determination of whether those remains are forensic or non-forensic. If the county medical examiner/coroner determines the remains are non-forensic, then they will report that finding to the Department of Archaeology and Historic Preservation (DAHP) who will then take jurisdiction over the remains. The DAHP will notify any appropriate cemeteries and all affected tribes of the find. The State Physical Anthropologist will make a determination of whether the remains are Indian or Non-Indian and report that finding to any appropriate cemeteries and the affected tribes. The DAHP will then handle all consultation with the affected parties as to the future preservation, excavation, and disposition of the 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 (NWRCP 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
- 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.
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.
Oiled Wildlife: Capturing oiled wildlife may be hazardous to both personnel and the affected animals. Incident personnel should not try to approach or capture oiled wildlife but should report any observations of oiled wildlife to the Wildlife Branch (Operations Section). For more information see the Northwest Wildlife Response Plan (NWACP Section 9310).
Wildlife Refuges and Wilderness Areas: This GRP area contains portions of the Lake Chelan-Sawtooth Wilderness, the Stephen Mather, and the Glacier Peak Wilderness Federal Areas. There is also a state (WDFW) wildlife area present within the southeast portion of this area.
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.