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This paper was written as part of the 2001 Alaska Ocean Sciences Bowl high school competition. The conclusions in this report are solely those of the student authors.

Eagle River: Past, Present, and Future

graphic

Written in part by each of the following:
David Breiler
Danielle Coombs
Jolene Rearick
Jan Tomsen
Andrew Sullivan, coach

Chugiak High School team
Chugiak High School
PO Box 770218
Eagle River, AK 99577-0218
 

Abstract

The goal of this paper was to explore as many factors as possible, to consider all avenues of influence on the future stability of Eagle River. Afterwards, a 50-year plan was developed for maintaining a healthy river. Three large goals dominated the plan: biological monitoring, streambank restoration (revegetation), and fish stream protection and enhancement.

Eagle River is part of the Anchorage watershed (USGS Cataloging Unit: 19020401) (Comprehensive Plan 1993). The river is located along the upper portion of Knik Arm, approximately midway between Anchorage and the Palmer-Wasilla area of the Matanuska-Susitna Borough and fed primarily by Eagle Glacier. Eagle River begins approximately ten miles north of the Anchorage metropolitan area and extends northeasterly for fifteen miles where it ends at the municipal boundary at the Knik River (Appendix A) (Comprehensive Plan 2000).

To the south and west of Eagle River and separating it from Anchorage is Fort Richardson Army Base. To the north and west, the area is bounded by Knik Arm, the northernmost extension of Cook Inlet. To the east lie the Chugach Mountains, most of which are located within Chugach State Park (Comprehensive Plan 2000).

Most of Eagle River, besides its upper region, is situated on a relatively narrow lowland, approximately 65 square miles in area, which is wedged between the Chugach Mountains and the Knik Arm. The lowland has forested undulating terrain that is bisected by four significant stream systems which drain the area from the mountains to the inlet including Eklutna River, Peters Creek, Fire Creek, and Eagle River (Comprehensive Plan 2000).

Historical Perspective

Pre-mid 19th Century

Eagle River provided a center of lifestyle for the seasonally nomadic, Athabascan Indians including fishing, hunting, and gathering. Eklutna is the oldest continually inhabited Athabascan site in the Chugiak-Eagle River area. Initially, Eklutna was a winter settlement, but by harvesting local water supplies such as Eagle River, it became a permanent year-round settlement for the Eklutnas, a Tanaina Athabascan group living in the Cook Inlet area (Comprehensive Plan 1993).

Early 19th Century–Present

The transition of Eagle River to the twentieth century began with early mining ventures and with the construction of the Alaska Railroad in 1923. The human factor magnified significantly in 1924 when the U.S. Department of Interior established a home at Eklutna for Native children orphaned by the 1918 influenza. Homesteading launched around Eagle River in the 1930's as a result o the establishment of Matanuska Colony (Comprehensive Plan 1993).

With the outbreak of the Second World War in 1939, part of Eagle River was segregated to the establishment of Fort Richardson Military Reservation. To this day, the basin of the river has suffered immensely due to ammunitions and leakage of toxic chemicals (Comprehensive Plan 1993).

The 40's and 50's saw a rapid population growth of 4,229 in 1939 to 82,736 in 1960 of the Anchorage area (Comprehensive Plan 1993). The large growth posed potential threats to the river. As the settlements grew, the need for public services rose leading to a destruction of wildlife habitat around Eagle River (Comprehensive Plan 1993). The growth was bolstered as a result of the Trans-Alaska pipeline from 1980 to 1985.

Today, Eagle River is fairly stable, but with the increasing demands of the community, the future cannot be completely ascertained. The institution of Chugach State Park has provided some relief.

Natural Environment

Vegetation

Eagle River hosts numerous aspects of natural vegetation (Appendix B). Vegetation types are defined as follows:

  • Coniferous — white spruce with an understory of wild rose, alder, and willow;
  • Deciduous — bird, black cottonwood, quaking aspen, alder, and willow;
  • Mixed — white or black spruce, birch, poplar, alder, and cottonwood (understory species include wild rose, grasses, devil's club, and ferns);
  • Shrub — devil's club, red-osier dogwood, willows, and blueberries;
  • Forested Bog — black spruce;
  • Open Bog — sphagnum moss and low shrubs, with sedges, rushes, and cottongrass (bog rosemary, labrador tea, shrub willows, and bog cranberries);
  • Alpine Tundra — herbaceous and shrubby, low mat plants (Johnson 1995).

Wildlife

Eagle is a critical habitat for many species of animals. The following animals are defined as follows:

  • Bald Eagles — eagle populations seem to be increasing; 32-40 inches high; wingspan up to 7 1/2 feet; chiefly feed on dead or dying fish, small animals; lay 2 to 3 eggs;
  • Bears — two types of bears (black and brown); diet consists of plants (70%), insects, and salmon;
  • Beavers — Alaska's largest rodent; lives in dens dug into the banks of rivers or lakes; cache food for long winters such as bark and cambium beneath the bark; provided problems in past and present by damming the river, causing floods;
  • Birds — home to many of Alaska's 443 species;
  • Red Fox — weigh 6-15 pounds; prey on voles, mice, rabbits, squirrels, insects, and birds; normally solitary, pair up 6-8 weeks a year;
  • Moose — largest member of the deer family; males 6 1/2-7 feet tall; weigh 1,200 to 1,600 pounds; life span of 16 years; feed on willow leaves and grasses in the summer, twigs and branches in the winter;
  • Porcupine — slow moving plant eaters; do not throw their quills, but flip its tail at its enemy;
  • Rabbits — snowshoe hares at the basin; fur white in the winter and brown in the summer; 8-12 year population cycles
  • Squirrels — two species (red and ground); feed on seeds, root's bulbs, plant stems, insects, and bird eggs;
  • Wolves — several wolf packs; typical wolf pack has 6-12 members; territories range from 300-1,000 square miles; feed on moose, Dall sheep, small mammals (Heacox 1996).

Fisheries

Eagle River is a residence for grayling, rainbow trout, Dolly Varden, sculpin, stickleback, and all five species of salmon. Eagle River is not large enough to support a functioning, commercial fishery, but it does harbor recreational fishery as annotated by the "Anchorage area sport fishing effort" (Appendix C).

Eagle River is relatively unproductive concerning salmon populations due to the population growth of nearby human communities, construction, and the high silt content. The Eagle River chinook salmon stocking program was designed to generate 6,000 angler days of effort directed at chinook salmon annually. In 1990, an annual stocking program was initiated in Eagle River with approximately 105,000 chinook salmon smolt of Ship Creek origin (Stratton 1995).

From 1982-1991, angler effort averaged about 2,300 angler-days in Eagle River. In 1992, the first year of the chinook fishery, effort was estimated at about 4,900 angler-days; chinook catch was estimated at 109, and harvest was estimated at 48 (Stratton 1995).

Currently, management activities for the Eagle River chinook salmon fishery include conducting chinook salmon escapement counts in South Fork to assure achievement of the 300 fish escapement goal.

Surficial Geology

Eagle River has two major bedrock types. The first is a relatively soft sedimentary rock which is typically found beneath lowland areas west of the Chugach Mountains. The second is higher metamorphic and igneous rock found in the Chugach Mountains (Comprehensive Plan 1993).

Surficial materials include those which were left by the movement of glaciers and streams, or were induced by gravity. The most common glacial deposits are moraines which typically consist of accumulations of earth and stones. Estuarine deposits were left by moving water, such as those along the edge of Knik Arm; pond and bog deposits; and glacial lake deposits, found in Eagle River Valley (Comprehensive Plan 1993).

Human Environment

Population

A substantial growth in population is predicted within 50 years around Eagle River. Based on past trends in population growth and the local share of the overall municipal population, the base, or middle 2010 population projection of 45,152 has been set around the Chugiak-Eagle River area by the Department of Community Planning and Development (Comprehensive Plan 1993). At this population level, the Chugiak-Eagle River specifically would have 15 percent of the total municipal population by 2010, up from 11 percent in 1990 (Comprehensive Plan 1993). The projection represents a healthy annual growth rate of about 3 percent, without applying excessive pressure on public facilities and services (Appendix D, E). However, it is almost impossible to properly predict the effect on the river.

Transportation

The increase in population will strain current transportation routes. Therefore, new roads must be constructed which could have adverse affects on Eagle River or indirectly through the surrounding wildlife and vegetation (Appendix F,G,and H).

The average daily traffic volumes on Chugiak-Eagle River arterials and freeways are projected to increase an average of 41 percent between now and the year 2015 based on studies by the Department of Community Planning and Development (Transportation Plan 1997). The total volume of traffic on area roads is not very informational in and of itself. In order to be meaningful, traffic volumes must be converted to Level of Service. Level of Service is a useful way of defining how well a particular street or road is operating and whether or not its capacity it being exceeded. Levels of Service range from A to F, with LOS A describing primarily free flow operations and LOS F describing forced or breakdown flow (Appendix I,J) (Transportation Plan 1997).

Chemical Wastes

A variety of wastes exist in or around Eagle River that are currently being monitored. Stringent requirements exist for the disposal of wastes involving potential criminal and civil liability on both organizations and individuals. Common chemicals disposed of around Eagle River are as follows:

  • 1,2,4 — Trimethylbenzene;
  • Benzene;
  • Ethylbenzene;
  • N-Hexane;
  • Toluene;
  • Xylene (Mixed Isomers) ("Envirofacts" 2000).

Generally, besides chemical wastes, there are three types of wastes. Chemical wastes involve those wastes that are harmful to human consumption, environmental cleanliness, or cause adverse symptoms in water, air, and soil. Biological wastes include diseases, feces, and transmitted bacteria. Radiochemical wastes are those wastes that have radioactive characteristics or high concentration of radioactivity (Clesceri 1990).

Water Quality

The Eagle River water supply is generally portable but not potable, difference being, the water is healthy for the environment but not safe for human consumption. An interview with Carole Lloyd, naturalist, revealed that in the upper region of Eagle River near the Nature/Visitor Center, water seemed to have optimal levels of temperature, pH, dissolved oxygen, total dissolved solids, alkalinity, oxygen reduction potential, and fecal coliform. However, as mentioned earlier, the base of the river is highly contaminated by explosive ammunition (interview November 4, 2000).

Of the contaminants that do exist in the water, most are caused by soil runoff and erosion of natural deposits. From the "1999 Annual Water Quality Report," the Anchorage Water and Wastewater Utility Treatment Division held the following contaminants including arsenic, barium, cadmium, chromium, copper, fluoride, mercury, nitrate, selenium, and thallium (Appendix K). The monitoring of these contaminants is critical for public and environmental safety. Appendix L shows a listing of water usage in the Anchorage area based on local water sources like Eagle River ("1999 Water Use for 19020401" 2000).

50-Year Plan

Biological Monitoring

Today, it is generally understood that human health and welfare are tied directly to environmental quality and that human activities can affect the environment in a number of ways. Watershed programs have been developed to protect our abundant supply of clear water by taking a cooperative approach to watershed protection. With society's leap into the 21st century, our priorities for water quality monitoring should expand to a greater scope. Therefore, a system of biological monitoring is essential.

Biological assessment (bioassessment) is the use of living organisms to tell us something about the environment. The examination of biological communities, particularly stream insects (benthic macroinvertebrates) provide a direct correlation to water quality (Water Quality 2000).

There are five reasons why macroinvertebrates are used for monitoring:

  • They are plentiful in most streams.
  • They can be collected quickly and easily.
  • They reflect cumulative impacts to an aquatic system over a relatively long period of time.
  • They provide a link in the food chain between primary producers and fish.
  • They are an inexpensive monitoring tool that anyone can use.

We propose that this suggestion should be based on the preexisting "rapid bioassessment" present already here in Alaska. We feel it is an effective tool and provides an effective connection between living components within an ecosystem. In addition, implementing such a program will not require a long process of legality, structuring, and development. An example of a water quality data sheet from the "rapid bioassessment" handbook has been provided (Appendix M) (Water Quality 2000).

Fish Stream Protection and Enhancement Strategies

A review of Eagle River indicates that it is still weak in supporting a strong, viable fishery, especially salmon. One suggestion developed by the Alaska Department of Fish and Game is installing flumes (Appendix N). It might be the first crucial step for later development practices. There are six significant notes about flumes keeping in mind that our overall purpose is to build a strong, viable fishery. The exact procedure encompassing the construction will be reviewed at the presentation ("Stream Fluming Techniques" 2000).

  • Fluming enables a utility or pipeline trench to be isolated from the stream flow, which reduces stream pollution. Vehicular access across a stream is also provided
  • Flumes (temporary or permanent pipes) can be used in streams up to 100 cfs. Timing should coincide with the low flow period, unless sensitive life stages or the presence of ice are more critical.
  • Fluming procedures may vary according to site-specific conditions.
  • Pipes must be large and strong enough to handle the maximum flow of the streams. Except for the smallest streams, corrugated metal pipes (cmp) must not be used because they will not support the weight of the water. Ductile iron or other heavy metal pipes must be used.
  • The length of the flume is dependent on the stability of the trench. The more unstable the walls or deeper the trench, the longer the pipes.
  • Flumes can be used in the winter, when ice can be placed on top, or in the summer when clean fill can be placed on top, but cover is not required.

Revegetation

The primary focus of the Eagle River 50-year plan is revegetation. A variety of soil bioengineering techniques have been developed to protect and restore damaged streambanks for the benefit of fish. In each case, the selection of a specific technique depends largely on existing site conditions that dictate how, when and to what extent a given technique is applied. Important factors to consider are: stream hydrology, bank stability, icing conditions, soils, surrounding vegetation, and the causative agent(s) responsible for the observed damage. Perhaps the most popular mode of revegetation is dormant cutting ("Streambank" 2000).

It is necessary to have a clear idea of how the restored streambank will function once work on the site is complete. Design features must anticipate post-restoration use of the site such as recreational use, boat tie-downs, and erosion control. Design features must also incorporate design elements that provide for fish habitat while preventing additional damages ("Streambank" 2000). The techniques for revegetation, which will be discussed in full depth including benefits, consideration, and construction at the presentation, may be used singularly or in combination to achieve desired results.

Conclusion

In review, we feel that the data presented demonstrated that Eagle River is experiencing a transitional stage between a naturally, viable environment to a humanly, impacted environment. Many factors were considered which emphasized both negative and positive aspects. The general opinion concerning the proposed plans is one of confidence and determination. However, we acknowledge the fact that a suggestion can only be made to be true or false until it is utilized.

Works Cited

Alaska Atlas & Gazetteer. (1992). Freeport: DeLorme Mapping.

1999 Annual Water Quality Report. (1999). Anchorage: Anchorage Water and Wastewater Utility Treatment Division.

Chugiak-Eagle River Comprehensive Plan: Municipality of Anchorage (Assembly Ordinance 92-133). (1993). Anchorage: Department of Community Planning and Development.

Chugiak-Eagle River Transportation Plan. (1997). Anchorage: Department of Community Planning and Development.

Clesceri, L. S., Greenberg, A. E., Trussell, R. R. (Eds.). (1990). Selected Physical and Chemical Standard Methods for Students. Baltimore: Port City Press.

"Envirofacts Report on Equilon Anchorage Terminal." Environmental Protection Agency Home Page. http://oaspub.epa.gov/enviro/multisys2.get_list?facility_uin=AKDO55503825. (10 Oct., 2000).

Heacox, Kim. Visions of a Wild America. (1996). Washington D.C.: National Geographic Society.

Johnson, D., Kershaw, L., MacKinnon, A., & Pojar, J. (1995). Plants of the Western Boreal Forest & Aspen Parkland. Edmonton: Lone Pine Publishing.

Pratt, Verna E. (1989). Field Guide to Alaskan Wildflowers: A Roadside Guide. Anchorage: Alaskakrafts, Inc.

Stratton, Barry and Paul Cyr. (1997). Area Management Report for the Anchorage Area, 1995 (Fishery Management Report No. 97-1). Anchorage: Alaska Department of Fish and Game.

"Streambank Revegetation and Protection: A Guide for Alaska." Alaska Department of Fish and Game Home Page. http://www.state.ak.us/local/akpages/FISH.GAME/habitat/geninfo/webpages/techniques.htm. (10 Oct., 2000)

"Stream Fluming Techniques." Alaska Department of Fish and Game Home Page. http://www.state.ak.us/local/akpages/FISH.GAME/habitat/geninfo/techassist/flumepic.htm. (10 Oct., 2000).

Water Quality Monitoring Field Guide. (2000). Anchorage: Environment and Natural Resources Institute University of Alaska Anchorage.

"1990 Water Use for 19020401." The United States Geological Service Home Page. http://water.usgs.gov/cgi-bin/wuhuc?huc=19020401. (10 Oct., 2000).

 


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