FINAL - ENVIRONMENTAL IMPACT STATEMENT CHENA RIVER LAKES PROJECT FAIRBANKS, ALASKA

PREPARED BY

ALASKA DISTRICT, CORPS OF ENGINEERS

ANCHORAGE, ALASKA

7 SEPTEMBER 1971 CHENA RIVER LAKES FLOOI} CONTROL PROJECT Fairbanks, Alaska

( ) Draft (X) Final Environmental Statement

Responsible Office; Alaska District, Corps of Engineers, Anchorage, Alaska

1. Name of Action; (X) Administrative ( ) Legislative

2. Description of Action; The project, authorized by the Flood Control Act of 1968, is a multiple-purpose project located in Interior Alaska, near the City of Fairbanks. The recommended project is designed to protect the City of Fairbanks and surrounding community from damaging floods originating on the Tanana and Chena Rivers by a combination of two methods; two earthfill dams to regulate and restrict the Chena and Little Chena Rivers, respectively, and a Tanana River levee system. Construction is scheduled to commence in April of 1973.

3. a. Environmental Impacts: The project will provide flood protection; dislocate 32 families and/or businesses; impound 2200 acres of terrestrial habitats and 2 miles of natural stream section; accelerate development of the protected flood plain; provide recreational opportunities, and may provide habitat for fish and wildlife species.

b. Adverse Environmental Effects; Loss of plants and animals in 2200 acres of terrestrial habitats to be impounded; loss of plants and animals in 1000 acres of habitats to be occupied by flood control structures; possibility of water quality problems in reservoir and dis­ charge water; and termination of periodic downstream flooding will be adverse to those plant communities dependent on such inundation.

4. Alternatives; "No development;" alternative dam site; floodway; levees; relocation; and flood plain management.

5. Comments Received:

State of Ak., Dept, of Natural USDA, U. S. Forest Service Resources, Div. of Parks USDI, Alaska Power Administration Dept, of Interior, Bureau of Sport Alaska Conservation Society Fisheries & Wildlife Environmental Protection Agency, Dept, of Interior, Nat. Park Ser. Water Quality Office Dept, of Interior, Bureau of USDI, Geological Survey, Water Land Management Resources Division Dept, of Interior, Bureau of USDI, Soil Conservation Service Outdoor Recreation

6 . Draft Statement to CEQ: 23 July 1971:

Final Stateme to CEQ: 2 7 OCT ^71 FINAL

ENVIRONMENTAL STATEMENT

CHENA RIVER LAKES FLOOD CONTROL PROJECT FAIRBANKS, ALASKA

Prepared by

ALASKA DISTRICT, CORPS OF ENGINEERS

ANCHORAGE, ALASKA

7 September 1971 FINAL ENVIRONMENTAL STATEMENT CHENA RIVER LAXES FLOOD CONTROL PROJECT Fairbanks, Alaska

Project Description. The Chena River Lakes project is located near Fairbanks, Alaska. Fairbanks, the second largest city in Alaska (45,000 population), is located 400 road miles northeast of Anchorage and 100 miles south of the Arctic Circle. The project was authorized by the Flood Control Act of 1968 for flood control, recreation, and fish and wildlife enhancement. This multiple-purpose project is designed to protect approximately 72,000 acres of the city of Fairbanks and adjacent Chena Rivers Valley from damaging floods originating from the Tanana and Chena Rivers by a combination of two methods; two dams to regulate and restrict the Chena and Little Chena Rivers, respectively, and a levee system along the Tanana River. Characteristics of the project features" are given below in tabulated form;

TABLE I. DIMENSIONAL DATA, CHENA RIVER FLOOD CONTROL PROJECT

Moose Creek Little Chena-Tana'na Dam Chena Dam River Levee

Length 7 .1 miles 4,675 feet 27 miles

Average Height 30 feet 60 feet 12.5 feet

Top Width 24 feet 30 feet 12 feet

• T°P Elevation +525 m.s.l +655 m.s.l. Variable

Embankment 5 million 1.9 million 4.0 million Volume cubic yards cubic yards cubic yards

Freeboard 3 feet 6 feet 3 feet

Recreation Pool Elevation +500 m.s.l.

p° o1 North 700 acres Surface Maximum 2,500 Area South 1500 acres cres

p° o1 North 1 mile x 1 mile 6 miles x Dimension South 2 miles x 3 mis. 2 miles long

Mean North 10 feet Depth South 5 feet _ Moose Creek Dam and Reservoir. The Moose' Creek Dam is located about 17 air miles cast of Fairbanks. This dan will divert fiocd 2 *. ,\:r. fro m the Chena River into the Tanana River to prevent flooding in the vicinity of Fairbanks. The accompanying storage reservoir, which will be formed by the annual spring runoff, will be divided into two pools by a low, im­ pervious rockfaced overflow sill. This sill will be located about mid­ way along the dam and will extend eastward (about 2,500 feet) from the dam until the top intersects natural ground at elevation plus 500 feet v mean sea level (m.s.l.).

The maximum probable flood stage (elevation plus 522 feet) could inundate up to 10,000 surface acres (behind the dam). Moose Creek reser­ voir level will range between 500 and 522 feet, remaining at 500 feet except during flood control operation. The reservoir level will be above the permanent pool elevation of 500 feet from several hours to several v/eeks depending upon the magnitude of the flood event. Vertical fluctuation will normally be about 2 to 3 feet with the maximum probable flood creating a 22-foot (plus 522 feet m.s.l.) vertical pool fluctuation.

Flexibility will be stressed in project design so that operation schemes may be revised and adjusted according to further recommendations from environmental agencies. Although an operation plan is pending further research studies, a preliminary reservoir operation schema is conceived as a three-phase seasonal plan.

a. Phase one: As spring flood flows subside, the south pool will either be drained into the Chena River or free passage will be provided allowing salmon snolts, which are migrating downriver at this time, to continue their downstream movement. Draining will be accomplished by constructing a drainage channel connecting the south pool with the Chena River. This channel will also facilitate seepage•collection and the passage of the south pool fish population to the Chena River. If drained the south pool will then be filled again for summer recreation purposes.

b. Phase two: At other than flood stages the plan provides for a summer-season reservoir pool (at elevation 500 feet) of-about 2,200 acres.

c. Phase three: The third phase of yearly operation will consist of draining the south reservoir before freezeup due to the relatively shallow condition of tie south pool and its questionable capability for sustaining a fish population during the winter. This will leave the 700- acre north reservoir as a permanent body of water throughout the year. The north pool, with deeper water and better circulation may be able to sustain a year-round fishery population.

A fish passage facility will be located on the Chena River to enable resident and anadromous fish passage over the dam during flood or low flow stages. A fish passage facility is not anticipated for the Moose Creek spillway. The spillway and channel are designed'with the capability of allowing passage of migrating salmon. This spillway works (1,200 feet wide) will be located at ground elevation (+502 m.s.l.) and will lead into an 8,000-foot long channel (500-foot bottom width), directing Chena River flood flows into the Tar.ar.a River.

2 Diverting Chena River water into the Tanana River during fail high flow periods nay mislead migrating salmon. They could migrate past the mouth of the Chena River and proceed up the Tanana to the spillway works; therefore, the spillway will be designed to pass fish. .

The outlet works on the Chena River will include debris racks, control gates, and energy dissipators. The project will be accessible from the north or south. A public access road about 5 miles long will connect the project area with the Chena Hot Springs road on the north and the road on top of the dam will connect with the Richardson Highway on the south. Relocation of one mile of the Eielson spur of the Alaska Railroad, elevating 1/2 mile of the Richardson (Alaska) Highway to coincide with the elevation of the reconstructed Moose Creek dike, and associated new bridges to accommodate the relocated railroad and highway, respectively, are also an integral part of the project. The bridges, intended to span the Moose Creek spillway, will be 1,200 feet long. The ground in the v icinity of the bridges will be riprapped to withstand increased water velocities through the spillway section. In order to protect the area between the Moose Creek Bluff and Eielson Air Force Base from peak flood flows, a training dike, extending eastward from Moose Creek Bluff for about three miles, will also be constructed.

Examination of the present alignment of the proposed 48-inch Trans - Alaska pipeline indicates it will cross the southern portion of the Chena River Dam and Reservoir. The Corps of Engineers is maintaining close liaison with the Alyeska Pipeline Service Company to assure project compatibility. It is presently recommended that the pipeline be realigned to avoid any conflict with the project.

Little Chena Detention Dam. The Little Chena Dam and detention reser­ voir will provide only flood protection as high water flows will only be temporarily restricted (about a 1- to 2-week period) and not permanently impounded. The dam design incorporates an uncontrolled outlet works con­ sisting of two concrete conduits for downstream water release. Because little is known of the Little Chena fisheries resource, a passage facility will not be recommended until further studies indicate a demonstrated need exists.

Chena-Tanana River Levee. The levee system will be located along the north b -»k of the Tanana River from the reconstructed Moose Creek dike to the con'luer.ce of the Chena River and extending upstream on the Chena for approximately four miles. The structure will prevent flooding in the Fairbanks area by the Tanana River. A secondary effect caused by the levee will be the impoundment of water from interior runoff resulting from snowmelt and rainfall. Therefore, the levee will incorporate an adjacent interior drainage system. This will consist of a 24-mile long drainage ditch to convey runoff to five ponding areas which will have a total storage capacity of about 5,200 acre-feet. A pumping station will be provided to pump pond water over the levee into the Tanana River.

3 Flood protection, including economic development benefits (EDA), constitutes 987. of the project benefits leaving 27. attributable to recreation and fish and wildlife enhancement. Total cost of the project is currently estimated to be about $110 million. The current benefit-to- cost ratio for the total project is 2.9 to 1, indicating it is economically justified. Construction is scheduled to commence in April of 1973.

2. Environmental Setting Without the Project. Located within the Chena and Tanana River flood plains, project areas occupy elevations from 480 to 660 feet above mean sea level with adjacent hills and bluffs rising to 1,100 feet m.s.l. The Chena and Tanana Rivers drain areas of about 2,070 and 20,000 square miles, respectively, with respective channel capacities of 12,000 c.f.s. and 80,000 c.f.s. in the vicinity of Fairbanks.

The Tanana River Basin consists of a wide flood plain and a series of terraces. The flood plain is dotted with meandering streams, ponds, and peat bogs. The terraces rest on thick beds of stratified gravels.

The Chena River is about 150 miles long and flows a meandering course through a broad alluvial valley and is constricted only in its upper reaches. The two rivers have only a few major tributaries and are characteristically fed by small creeks and underground springs. The Tanana, although augmented by snowmelt, is primarily a glacier fed stream, while the Chena River exhibits both snowmelt and rain flood characteristics. In both rivers, flows rise gradually during spring breakup to a peak discharge although occasionally the rivers exhibit a second peak discharge in the fall because of heavy rains. Major floods result from snowmelt, rainfall, or a combination of the two. Peak volumes from combined snowmelt and runoff occur when a sudden rise in temperature combines with a warm rain on a saturated snow cover. During the 20-year period between 1948 and 1967, peak discharges resulted in spring floods 10 times, with fall floods occurring only twice. The only fall (rainfall) discharge which exceeded the spring peak snowmelt discharge was the devastating flood of 1967. Examination of this 20- year period shows the average Chena River flood stage duration to be one week and the time of flooding to be mid-May.

Like much of the State, Interior Alaska is a land of extremes. The climate of the Chena and Tanana River Basins is dominated by con­ tinental climatic influences which are characterized by cold, dry winters and warm summers. Severe winter temperatures occur because the mountain ranges lying to the south of the basin form an effective barrier to the flow of warm, moist air from the North Pacific Ocean. This leaves the basins under the influence of polar air masses flowing in from the north. Because of a lack of a moderating influence of maritime air, large annual and diurnal temperature amplitudes are exgerienced. The mean annual temperature is 25°F., with a maximum of 99 F. and a minimum of -66°F. recorded. The annual snowfall is

4 approximately 60 inches, mean annual precipitation is 12 inches, and average wind velocities are 4 to 6 miles per hour, predominantly from the north in winter months and southwest during summer months.

Much of Interior Alaska is underlain with discontinuous permafrost. Holes drilled along the proposed Trans-Alaska pipeline route show patches of permanently frozen gravels throughout the'Chena RiveVValley.' Within the flood plains the most predominant soils are the bog and alluvial types which exhibit their deposits of silt overlying stratified and unstratified gravels. Examination of the soil and exploration surveys conducted in the project area indicate there is zero to 10 feet of silt overlying deep deposits of clean sands and gravels. The explorations penetrated 200 to 250 feet without finding bedrock. Completed explorations have shown that no permafrost conditions exist along the proposed Moose Creek Dam alignment. There is a large area along the western side of the impoundment where the gravels are covered with 20 to 30 feet of permanent­ ly frozen silt. These areas of perma-frost contain a very low ice content and therefore no serious settlement or stability problems would result from construction efforts.

The Chena and Tanana drainage basins lie within the "spruce-birch" forest of the western extension of the boreal forest belt traversing North America. The we11-drained river bottoms and higher elevations produce favorable sites for heavy stands of white spruce (Picea glauca). cottonwood (Populus tacamahaca) and paper birch (Betula papyrifera). * Found on less favorable sites are a mixture of black spruce (Picea marlana), aspen (Populus tremuloides). and larch (Larix laricinaj. Associated riparian undergrowth usually consists of dense, mixed stands of willow (Salix sp.) and alder (Alnus sp.). At least 50 percent of the surface area throughout the Moose Creek Reservoir is a muskeg-bog type community with associated stunted tree (noncommercial) and shrub growth. Bog species tend to segregate along a moisture gradient which is created by changes in microtopography resulting from deposition along the original flood plain surface. These bog species consist of black spruce, ericaceous shrubs, dwarf birch and several species of mosses. The project area contains about 100,000 board feet (100 M b.m.) of merchantable timber, most all of which is located adjacent to the Chena River water course.

In this typically subarctic region, wildlife species vary according to seasonal habitat requirements. During summer months moose (Alces alces) are abundant in all habitat types from lowland muskeg to the upland areas. The "Forty-mile" caribou (Rangifer arcticus) herd is seasonally distributed throughout the Upper Chena River Basin. Grizzly and brown bear (Ursus arctos), black bear (Ursus americanusj. and a variety of furbearers and small mammals inhabit the two river basins.

5 A variety of furbearers, waterfowl, and upland game birds such as ruffed grouse (Bonasa umbellus) and spruce grouse (Canachites canadensis) are common inhabitants.

The Chena and Tanana Rivers provide habitat for a variety of fish species. Habitat exists for Arctic grayling (Thymallus arcticus), northern pike (Esox luclus), northern sucker (Catostomus catostomus), and burbot (Lota lota leptura) with lesser numbers of sheefish, sculpin, cisco, humpback whitefish, and lamprey. The Arctic grayling is the most important freshwater fish species in the Chena River and is utilized extensively by stream fishermen. The Chena River possesses excellent spawning habitat and supports a large population of grayling.

Egg-laden chinook salmon (Oncorhynchus tshawytscha) and chum salmon (0. keta) migrate up the Chena River to spawn. The salmon start their annual upstream migration in the ocean and progress up the Yukon, Tanana, and Chena Rivers. These salmon contibute to the commercial, sport, and subsistence fisheries of these rivers. Upstream migration (Chena River) of adult chinook and chum salmon starts in mid-July and mid-August, respectively. The major portion of the salmon spawning area is located above the Chena River Dam site. Stimulated by spring breakup, the Chena River downstream migration of. young smolts start in May. The annual run of both species of adult salmon, approximately 200 chinook salmon and 1,000 chum salmon, is considered small. However, in perspective, they are the few individuals of the Chena River genetic stock to reach their spawning grounds after leaving the ocean 850 river-miles downstream.

Numerous recreational activities are available in the Fairbanks vicinity. The major recreation opportunities are hunting, boating, swimming, water skiing, camping, picnicking, fishing and wilderness hiking and canoeing. In the Fairbanks region, the lake-oriented recreational opportunity is limited to two small, overutilized and distant (40 miles) lakes— Birch and Harding Lakes. Exceptionally fine streams and stream fishing 3.reas are available and the most accessible waterways, such as the Chena River, are heavily utilized for fishing, canoeing, and river boating. That stretch of the Chena River from the termination of the Chena Hot Springs road downstream to Fairbanks is the most heavily utilized portion of this river. The increasing population of Fairbanks and the tourist traffic are causing an increasing demand on the existing recreational facilities.

Economic employment consists of a large segment of the labor force being employed by the military establishments and Government. These two categories account for one-third of the labor force in the city of Fairbanks and nearly two-thirds of that in the Fairbanks Trade Area. Many of the remainder are engaged in construction and varying service- type industries which serve the military establishment. The University of Alaska, with its associated research institutes and facilities, is also an important factor in the economy of the area.

6 Fairbanks has been the center of much attention due to the discovery of oil in commercial quantities on the Arctic North Slope of Alaska. As the principal service community for some 275,000 square miles of the Interior, the city can be expected to benefit from future oil develop­ ments.

In the past and as presently evidenced from the many acres of mine tailings, metallic mining activity in the Fairbanks area has been associated with gold ore; however, today most gold mining activity has been terminated. There are abundant coal reserves in the area and pro­ duction is currently competitive with other fuel sources. Prospects for a coal based industry are remote in view of the oil and gas potentials in the State. It appears that raining activity must await discovery of larger or higher grade mineral deposits than are presently known, or upon technological advances that would permit profitable exploitation of present deposits at present price conditions.

The Soil Conservation Service reports there are 7 0 , 0 0 0 acres of potential agricultural land located in the area beginning just below the Moose Creek Dam site and extending downstream to Fairbanks. Agricultural development in the Chena and Tanana River Basins, in the form of dairy products, potatoes, and hay production, is quite limited. Although high cost of agricultural production and limited opportunities for agricultural area development exist in the State of Alaska, the great distances from other producing areas in the contiguous states could make farming of these restricted areas feasible.

According to the published list "Rare and Endangered Fish and Wild­ life of the United States," issued by the Bureau of Sport Fisheries and Wildlife, no rare or endangered wildlife species are known to inhabit the project area. Examination of the "National Register of Historic Places," as required by the National Historic Preservation Act of 1966, indicates there are no officially designated archeological or historic sites in the project area.

3. Environmental Impact of the Proposed Action. The environmental impact categories associated with the project are: flood protection, family and business relocation, and water impoundment. Also, water quality, recreation, and fish and wildlife aspects are interrelated and associated with project impacts. The impact categories identified are similar for each separate project phase, though £ot necessarily the same; therefore, the-individual projects with their specific^im­ pacts will be discussed separately and in detail.

A. Moose Creek Dam and Reservoir. One of the major environmental impacts associated with this construction is the pre­ vention of flood damage to present and future Fairbanks urban com­ munities. Reduction of: (a) damage losses on about 7 2 , 0 0 0 acres of existing residential, commercial and agricultural property; (b)

7 hazard to life; and (c) personal inconveniences, will result from project development. These w ill allow a more normal livin g pattern in the Fairbanks area. An indirect environmental impact, generated by flood protection, will be the increased land values expected in the formerly flood prone areas. The Corps of Engineers will acquire all lands required for the project, including a finge area around the reservoir for recreation purposes. This facet of the project will be coordinated closely with local interests and governing entities prior to any acquisition. To insure that lands surrounding the reservoir and the newly protected area are properly zoned and developed (in harmony with nature), it would be desirable if an environmentally-oriented land use plan was devised and utilized to the fullest extent in the future. The possibility of uncon­ tro lle d , haphazard developments would probably lead to the usual sub­ standard private facilities and attendant access, as well as sanitation, pollution, and aesthetic problems. Although the Corps of Engineers has no authority to control or plan land uses on private lands, the Alaska Conservation Society has expressed a desire to see a land-use plan developed and has offered its expertise and assistance in accomplishing this task.

Nine families residing within the impoundment area w ill be dislocated. As "displaced persons" under Public Law 91-646 (approved 2 January 1971), they will be entitled to certain payments and services in addition to compensation paid for real property taken for the project. These include payment for actual, reasonable moving expenses and expenses of searching for a replacement house or business. Displaced persons are also entitled to assurances that prior to their displacement there is available safe, decent and sanitary replacement dwellings. Financial assistance in the form of supplemental payments is also available to insure their relocation- to safe, decent and sanitary dwellings.

Impoundment creates other major impacts and several secondary changes. The reservoir, as previously mentioned in the "Project Description" will be formed by spring runoff waters. The impoundment w ill be divided, by an impervious s i l l , into two pools (700 and 1,500 acres). The north pool w ill be maintained throughout the year, but the south pool may be drained in the fall, via a drainage channel. Diversion of flood waters from the Chena to the Tanana River w ill eliminate overbank flood flows in the Chena River flood plain below the diversion. This will also eliminate the deposition of silt and nutrients to which the present downstream plant communities are adapted and may have a detrimental e ffe c t on those communities.

Impoundment of the Chena River may produce physical, chemical, and b iological changes in the water downstream from the dam. The most c r itic a l problems are associated with changes in the temperature regime and dissolved oxygen content as water circulates through the pool and is released downstream. The reservoir will have a large sur­ face area in proportion to its volume and solar energy absorption will cause the surface layer of reservoir water to be warmer than the Chena

8 River water. Therefore, water discharged from the reservoir may cause a rise in temperature in the Chena River below the dam.

The Chena River is naturally low in dissolved oxygen during winter months and this could affect the survivial of fish in the permanent north pool. In order to prevent an accumulation (during winter months) of water low in dissolved oxygen content, the Chena River channel will be modified to provide circulation within the north pool. This may also have a beneficial effect on the temperature regime of the north pool.

It has been found that many shallow subarctic lakes exhibit an absence of thermal stratification. This was due, in part, from wind action on the lakes causing the water to continually mix. The Moose Creek Reservoir is generally aligned in a northeast-southwest direction. The prevailing summer winds usually come from the southwest and could act as a means for water circulation throughout the simmer.

Organic material new in place in the proposed reservoir area is a source of potential contamination. Construction plans call for the removal of all standing trees from the area to be inundated. The north pool area will be stripped of all organic material down to the mineral soil. In the south reservoir area, only those areas to be opened for borrow pits will be stripped. Therefore, there may be live and dead vegetation and humus remaining in the south pool to exert a biological oxygen demand on the water impoundment there.

Primary productivity in many arctic and subarctic lakes is relatively low. It has been found that nutrients were many times the limiting factor in primary production. Therefore, there may be a beneficial effect from leaving portions of the south pool unstripped of surface vegetation. The dissolved nutrients would probably be used in the biological productivity of the pool.

Little is known at this time about the expected sedimentation to be incurred within the reservoir. The Alaska Water Laboratory (E.P.A.) has done a limnological study which included some sedimentation investigations of the Lower Chena River. The Chena River is generally a clear-running stream except during spring breakup and the fall rain period. If a high degree of deposition occurs in the reservoir, this will have an effect on the secondary project purposes. This could necessitate the removal of the deposited sediment. Future studies will be conducted to project the sedimentation rate and what effect this will have on the reservoir ecosystems.

Limited data are available at this time about the ecosystems which will be affected by the proposed flood control structures; consequently, predictions of all the changes that might occur must be appropriately qualified. However, since there is some flexibility in the design of the structures and considerable flexibility in the operation and main­ tenance of the project, it is imperative that the necessary physical and biological data be gathered within the next 2 years. The University of Alaska campus is located only 25 miles from the proposed project area and many of the scientists there have expertise which the Corps of Engineers will utilize in these studies. 9 Spring fluctuations in the Moose Creek Reservoir— unlike many flood con­ trol projects--will be small and should not. present any real problems. The normal seasonal fluctuation will be about 2 to 3 vertical feet (500 to 503 feet elevation) and the associated horizontal fluctuation around the periphery of the reservoir will not be great. Horizontal fluctuation of the eastern shore of the south pool, which follows an old slough embankment, will only be about 2 to 3 feet. About 1 mile of the shore near the middle of the reservoir will experience the largest fluctuation— about 100 to 500 horizontal feet. These fluctuations are based on the capability of the control features, and expected flows through the dam. Changes in water levels should only occur as spring or fall flood flows are diverted through the impoundment area (except when the south poolis drained). Although little is known of the hydrologic response of vegetation in the sub-arctic, it is probable that a normal succession of plant species, compatible with and dependent on spring inundation, will be established. The area to be permanently inundated is 700 acres, and an additional 1,500 acres will be inundated only during the summer. The maximum probable flooded acreage would be 10,000 acres, but that area would be affected for a period of only 1 or 2 weeks and only in a year of extremely high water. These water levels will affect the habitats of resident wildlife species in various ways.

During summer reconnaissance flights, moose were sighted in the pro­ posed reservoir area. According to the Department of Fish & Game moose presently do not utilize the proposed impoundment area as winter range; however, areas adjacent to the project area are especially good wintering habitat. After construction moose will probably not utilize the project area to any significant degree during summer months due to recreation uses and consequent human disturbance. Caribou do not utilize the proposed impoundment area and consequently will be unaffected by the project.

■ Changing the present spruce-bog environment to a lake-oriented environment may affect waterfowl and furbearers. Many comments were received on the draft statement questioning the capability of the reservoir to produce waterfowl and therefore warrants' some discussion'.*" Several facts which need to be considered are:

a. Presently much of the shoreline habitat is provided by numerous pothole and oxbow lakes. When recharged during the spring, these pro­ vide about three times as much shoreline habitat as will be furnished by the impoundment. However, the potholes dry up and totally disappear by late summer, reducing available open water and Increasing shoreline vegetation.

b. Spring water levels and available shoreline habitat affect the availability of suitable waterfowl nesting and territory area which, in _turn, affect the species composition and size of the breeding population. The most utilized habitat is the *'floating bog-mat" found around the peripheral margins of eutrophic lakes. This vegetation mat takes several years to develop and will probably not develop in the Moose Creek reservoir for many years. c. Fluctuations in the proposed impoundment will be minimal. In addition, waterfowl in the Fairbanks area generally begin nesting between 25 April and 15 June. Any early-formed shoreline nests will probably be destroyed by a mid-May water (vertical increase) fluctuation. Because the nests are destroyed early in the season, this will make renesting very probable; however, experience has shown that renesting success is usually lower. Actually, the most important aspect is the number of ducklings fledg’d.

d. The impoundment may be utilized as a refuge for waterfowl during their molting period.

e. Recreation pursuits and consequent human disturbance may lim it waterfowl utilization of the reservoir area.

Because the waterfowl presently produced in the project area do not significantly contribute to the overall area production, it appears, quanti­ tatively, that the existing waterfowl populations may not be significantly affected by the project. If desired, the impoundment could be managed to produce feeding habitat to attract waterfowl during the hunting season. In addition, aquatic furbearers may favor the stable and year-round source of water (north pool) over the periodically drying potholes, but human disturbance may also limit their participation in populating the reservoir.

The reservoir will permanently inundate about 2 miles of the stream habitat on the main stem of the Chena River. Some of this^area is .... potential spawning habitat for grayling; therefore, this habitat and potential future production will be lost. During extreme flood stages, large flows will be passing into the Tanana River via the spillway structure. This will produce adverse effects on the grayling resources inhabiting the impoundment by flushing them into the Tanana River. The Tanana River carries an extremely heavy silt load making it undesirable to sport fishing; therefore, the fish (although unharmed) may not be available to sport fishermen. Dam construction near the Chena River will increase the turbidity level of the clear running river and this could prove to be adverse to any downstream spawning beds. The use of heavy equip­ ment within the river channel will be minimized. The Contractor will also be subject to all Federal, State and local water quality laws. The use 6f the north pool as a nursery or rearing areas is anticipated. Recommendations by the Federal and State fish and wildlife agencies for the mitigation of grayling will be incorporated into the project plan.

There is evidence that grayling and pike populations in Interior Alaska move downstream to winter and upstream in the spring to spawn. The Moose Creek Dam will incorporate a fish passage facility providing adequate passage for seasonal movements of resident fish species as well as the annual migration of anadromous fis h . The adult chum and Chinook salmon populations should be unaffected by the impoundment as spawning

11 grounds will not be affected and passage will be provided. Construction w^-bhin the river channel, during the annual upstream and downstream migration of salmon, will be minimized.

The potential will exist for a variety of recreational pursuits. Because recreation is a designated project purpose, lands could be acquired for this need. Any land acquisition for recreation will be coordinated closely with the local interests. Although inundating about 2 miles of the Chena River, the project will basically leave the river in a natural free-flowing state. The overall reservoir plan will provide areas for camping, picnicking, boating, skiing, swimming and scenic viewing with associated utilities and access roads. A boat transfer device is planned to facilitate the traversing of river boats over the dam at the Chena River.

The aesthetic resources of the area are emphasized by the scenic topography, low population density, and juxtaposition of wilderness type areas. The access road, connecting the Chena Hot Spring road with the project site, w ill facilitate public entry to the reservoir upon completion of the project. Access from the Richardson Highway w ill also be provided.

The number of man-caused forest fires will probably increase due to the increased intensity of use by campers and hikers. Although these fires may prove beneficial in providing browse (subclimax vegetation) for game species such as moose, the fires.will create aesthetically displeasing scars on the landscape. The access roads, however, will make the surrounding area more accessible for fire fighting equipment enabling the instigation of better fire control techniques.

The alignment of the proposed 48-inch Trans-Alaska pipeline will cross the Chena River Dam and Reservoir near Moose Creek Bluff. The Corps of Engineers and the Alyeska Pipeline Service Company are maintaining a close liaison to insure compatibility between the two projects. It is recommended that the pipeline be realigned so as not to interfer with the flood control structures. Any future real estate developments, or timber and mineral potentials of the inundated area will be lost.

Although borrow sites have not yet been chosen, material within the impoundment confines will be used unless impractical. Utilization of the silts and gravels from the reservoir will (1) enable the pool to be deepened and (2) eliminate the necessity for additional construction scars from borrow pits located outside the impoundment area. Clearing and borrow excavation in the south pool will be managed so as not to develop "potholes" which will trap fish upon fall draining. If material is needed from a site outside the confines of the project area, post- construction rehabilitation techniques such as landscaping (grading, slope scabilization, and drainage facilities) and revegetation of disturbed areas will be utilized. To shield these sites from public display, one hundred-foot natural wooded strips, as a visual buffer,

12 will be incorporated. If found desirable, any pit located outside the construction area could be rehabilitated and turned into camping areas to supplement the choice camping sites.

The visual aspect of the dam will be enhanced by landscape planting on the downstream face. Top soil and mature vegetation will be obtained from the impoundment area for restrorative landscape purposes.

During the cource of construction dust will be generated and therefore strict water and air pollution controls will be enforced.

B. Little Chena Dam and Detention Reservoir. The Little Chena Dam will provide downstream flood protection by retaining peak flood runoff and allowing a gradual release of the water. This will keep the Little Chena and Chena Rivers within their banks, but will extend the bankfull flow over that period required to discharge flood waters retained behind the dam. This will be a period of approximately one to two weeks. Be­ cause the dam outlet works are located at ground level and are big enough to permit the normal river flow without restriction, the detention dam will not impede normal flow regimes.

Operation of the Little Chena detention dam will have two effects on riparian vegetation. Above the dam the vegetation will be subjected to flooding for a longer period and to a deeper depth than has occurred in the past. Some plant communities which have never been inundated will be subjected to periodic flooding. Below the dam the stream will remain within its banks and not flood those riparian communities which have been adapted to such flooding in the past. The final effect of the changed moisture regime cannot be predicted with certainty at this time, but it can be assumed that there will be some changes in the composition of the vegetation along the Little Chena River. Changes in plant associations should have little effect on populations of the larger mammals and birds, but will cause local changes in the small mammal and bird populations.

Except for the occurrence of grayling in the stream, there is little known about the fish resources of the Little Chena River. Future in­ vestigations by the fish and wildlife agencies will provide data needed to assess the effects of the detention dam on fish population sizes and distributions. In the absence of a demonstrated need, no fish passage facility has been planned for the dam. The outlet structure is at stream bed level and should not impede fish passage during normal flow periods. If further investigation reveals the need for a fish ladder, or other passage structure, it will be incorporated into the construction plan.

Actual dam construction could temporarily increase the turbidity level of the Little Chena River but this may not prove detrimental as the river naturally carries a high sediment load. It has not been determined where borrow material will be obtained for dam construction, however, borrow areas will be located to allow minimum damage to wildlife and stream habitat. Top priority will'be given to precluding excavation from within the stream itself, allowing preservation of the freshwater

13 ecosystems of the Little Chena River. All postconstruction rehabilitation techniques described for the Chena River Dam borrow areas will be employed.

One family will be dislocated. Land acquisition and assistance will be conducted in the same manner as for the Moose Creek Dam. It will be necessary to construct an all-weather access road to the construction site which will secondarily provide public access for hunting and rec­ reation after the dam is completed.

Visual impact of the dam will be minimized by using fill material common to the area and by planting the downstream face of the dam with plant species indigenous to the area. This will, to some extent, enable the structure to blend with the natural surroundings and be aesthetically more pleasing to the eye. Expertise from the Soil Conservation Service will be utilized in the selection of plants and in determining proper planting methods.

C. Tanana and Chena River Levee System. Levee construction will provide the city and surrounding community with protection from flood flows originating on the Tanana River. Land acquisition and resettle­ ment of 16 families and six businesses will be required for the con­ struction of the levee and will be handled in the same manner as was described for the Moose Creek Dam. Diverting Chena River flood flows into the Tanana River will naturally increase the volume of water carried by the Tanana River and decrease the volume carried through Fairbanks by the Chena River. The portion of the Tanana River that will be affected will be between the diversion channel and the mouth of the Chena River. The Tanana River below Fairbanks will exhibit minor change in flows from what presently exists. Constricting the Tanana River flows with the levee system and increasing the volume of water (diversion of the Chena River) will increase the inundated area of the Salchaket Slough flood plain. With the absence of developments in this flood plain, any increased inundation will not prove detrimental. Actual levee con­ struction should temporarily increase the turbidity of the Tanana River but this will not prove detrimental to the stream system as the river is naturally very turbid. Borrow sites have not yet been specifically located. Any site location along the Tanana River high flow channel may produce holes to trap fish during low flows; however, the heavy bed load and the large natural movement of sediment within the river is expected to fill in any excavated locations. Borrow areas which have not filled in and may act as fish traps will be corrected by means of leveling; therefore, the levee system should not have a detrimental effect on anadromous or resident fish species. Any dry land borrow pits will be rehabilitated in the same manner as was described for the Chena River Dam and Reservoir.

The present alignment of the levee may interfere with airport expansion plans. In addition, the levee may impede air circulation and could contribute to additional ice-fog problems. Further study of the levee route during the

14 engineering design phase of the project will take into account the ice-fog conditions and airport expansion plans.

'Vegetation removal is unavoidable but not a significant environ­ mental. aspect. Visual impact of the levee will be minimized by land­ scaping and planting techniques. Because of the thorough rehabilitation measures and through coordination with the responsible agencies, plans could be developed to create camping areas from the borrow sites. Con­ sideration will also be given to providing walkways along the berm and strategically placing suitable plantings to aesthetically enhance any recreational potential.

4. Any Adverse Environmental Effects Which Cannot Be Avoided Should the Proposal Be Implemented. Adverse effects associated with the proposed project will be:

a. Loss of plants and small animals in approximately 700 acres of ter­ restrial habitats to be permanently flooded.

b. Loss of plants and small animals in approximately 1,500 acres of terrestrial habitats to be flooded only during the summer.

c. Loss of plants and small animals in approximately 1,000 acres of habitats to be occupied by dams and dikes.

The exact magnitude of these effects is unknown at this time, but the areas affected have not been identified as critical game winter ranges, calving areas, or critical nesting areas. No rare or endangered species will' be affefcted.

d. Termination of periodic downstream flooding.

This is the purpose of the proposed project and it will be beneficial in terms of protecting human lives and property. However, there will be an adverse effect on those plant communities which require periodic flood­ ing with the associated deposition ox silts and nutrients.

e. Permanent rise in water level along 2 miles of the Chena River stream habitat and loss of any spawning beds therein. f. Generation of dust.

S. Another possible adverse environmental effect could be a rise in water temperature either within the pool or below the dam.

There may be other adverse effects which are not predictable at this time but which will become known after the flood control scheme has been in operation for several years. Since construction and operation plans are still flexible, a research program should be undertaken to determine the effects of various operational practices on water temperatures, dissolved

15 oxygen levels, nutrient levels, aquatic biota, and silt deposition, bot% within the reservoir and downstream.

Alternatives to the Proposed Action. Comprehensive flood damage prevention planning requires integration of ail alternative.measures in investigation, of flood problems and planning of practical flood plain management programs. These programs should include structural develop­ ments, non-structural methods, or a combination of measures. Structural measures are considered to be developments to lower flood heights or provide barriers against flood waters. Non-structural measures are considered to be all other procedures for reducing flood damages and damage potentials, including flood proofing of buildings, building codes and zoning.

Many alternative developments such as levees, reservoirs, channel improvements, diversion floodways, non-structural measures, and combi­ nations of the above were considered. This statement will present the alternatives (in table form, page 17), both structural and non-structural which were considered to be most feasible. '

a. Non-structural.

(1) Relocation. Relocation of all buildings and utilities within the flood plain was cursorily examined and determined uneconomical (higher cost than the recommended plan). This was because of the magni­ tude and value ($450 million - 1967 cost) of the existing facilities within the flood prone area.

W Plain Management. Flood Plain Management includes such measures as building codes, flood proofing, and land use zoning. Although these non-structural measures were considered, no detailed studies or comparative analyses were conducted. At the time of project formulation, flood proofing the existing buildings was thought to be prohibitively expensive. The city of Fairbanks is developing a building code (taking effect 1 January 1972) which will require that all structures built within the designated flood plain will be designed so as not to be subjected to damage from an intermediate regional flood.

(3) No Development. "No development" would not prevent annual flood damages to the existing communities. Flood damages incurred in 8 and 1967 were $14.8 million and $84.5 million, respectively. The City of Fairbanks would also not experience the direct or indirect economic benefits of the money spent on the proposed flood control structures. However, with the inauguration of appropriate building'codes, relocations, zoning, and other appropriate land use practices the flood damages in Fairbanks would decrease over the years.

16 TABLE 2. ALTERNATIVES - CHENA RIVER LAKES FLOOD CONTROL PROJECT

Development Alternative Combinations

. 2 3 4 5 6 7 *8 a. Non-structural

Relocation x

Flood Plain Management x

No Improvement x b. Structural

Chena River Levees x

Moose Creek Floodway

Tanana River Levee (south bank) x

28-Mile Chena River ::

L ittle Chena Detention Dam x x x x

Chena-Tanana River Levee (north bank) x x ::

Moose Creek Dam and Reservoir x x

★ Recommended Project Combination

b. Structural.

(4) Levees. Several levee systems along both banks of the Chena River were studied. Levees, without any upstream regulation, would be required along both banks from the mouth of the Chena River upstream for 25 miles. Typical levee sections would have an average height of about 35 feet and require 350 feet of right-of-way for con­ struction. This width would be needed for relocation of utilities and buildings, reconstruction of all bridges crossing the river and location of extensive borrow areas. If the Chena River is an aggrading river system, it could result in future maintenance problems and creation of a need to increase the height of the levee. Only flood control benefits would be realized by a levee system.

17 (5) Floodway. The plan selected by the Corps for study consists of a detention dam on the Little Chena, a diversion floodway on the Chena River and a levee along the Tanana River. This project would not permanently inundate any portion of the Chena River and therefore no fluctuations in temperature regimes would be expected. Restricting fish passage would not be expected with a fish passage facility on the Chena River. However, during periods of high flow diversion, resident fish could be diverted into the unfishable Tanana River. Vegetation responses to the diversion of water are not known but could be expected to be the same as that experienced along the upper water levels of the recommended plan. Little is known at this time about the expected deposition of sediment or the effects deposited sediment might have on the floodway vegetation. This alternative would provide flood protection equal to that of the recommended plan but at a slightly greater cost and there would be no benefits from recreation or fish and wildlife enhancement.

(6) Salchaket Slough Diversion. A combination involving the same structures as the recommended plan but moving the alignment of the Tanana levee from the north bank to the south bank has also been con­ sidered. The Salchaket diversion is a scheme to divert the Tanana River, using a diversion dam across the Tanana River, from its present river course into an existing slough (overflow channel of the river) and to contain it in this slough by means of a levee for some 23 miles. The river would re-enter the existing water course west of the City of Fairbanks. A brief restudy of this diversion scheme in 1970 (based on 1967 prices) produced a cost figure of $17.8 million compared to $13.0 million for the north side levee. Because of the cost difference and the environmental unknowns, no further study was given to the slough diversion.

The major advantages of the Salchaket Slough diversion are: more area in the city would be protected from flooding; the high ground water table in the south area of the city may be lowered, making the bog- muskeg lands more usable; the cost of obtaining right-of-way for the north side scheme (90% State financed, 10% City-Borough) is about $6 million (1971 prices) and the cost of land for the Salchaket scheme is negligible; a source of gravel for construction use would be exposed in the old river bed; no relocations of roads, utilities, or private dwell­ ings are required; and no pumping plant or ponding areas are required. The major disadvantages of the Salchaket Slough diversion scheme are: the north side levee scheme is cheaper based on 1967 prices; diversion of the Tanana River represents a major engineering problem which, when fully analyzed, could increase costs considerably; construction access is more difficult on the south side of the river; inundation of the bog land south of and in line with the airport runways could attract water- fowl which might interfere with air traffic; and elimination of moose habitat.

Little is known of the expected impact of the diversion on the fishery resources or of the response of peripheral vegetation along the new river channel. The vegetation and small animals occupying the pro­ posed channel would be eliminated.

18 (7) Dam Construction. The Chena River 28-mile Dam and Reservoir, Little. Chetna detention dam and the Tanana.River levee, system comprise* this alternative which differs from the recommended project primarily in the site location of the dam on the Chena River and the difference in the two dam structures. For this reason the foregeing^remarks are restricted to the impact of the 28-mile Dam and Reservoir.\ The following dimensional characteristics of this alternative are listed

TABLE 3. DIMENSIONAL DATA, 28-MILE CHENA RIVER DAM AND RESERVOIR PROJECT

Crest Length 2.4 miles

Average Height 120 feet

Top Width 24 feet

Crest Elevation +715 m.s.l.

Embankment Volume 15 million cubic yards

Freeboard 9 feet

Surface Area of Reservoir Pool Maximum Pool - 16,000 acres Summer Recreation Pool - 12,160 acres

Storage Capacity of Reservoir Maximum Pool - 820,000 acre-feet Summer Recreation Pool - 420,000 acre-feet

Reservoir Elevation Maximum Pool - +706 m.s.l. Summer Recreation Pool +676 m.s.l.

Length of Reservoir Pool Maximum Pool 12 miles Summer Recreation Pool 9 miles

★Cost - 28-mile Dam and Reservoir $48,600,000 Little Chena Dam 11,700,000 Tanana River Levee System 16,900,000

★Construction cost only

The 28-mile project would block the passage of fish and in doing so eliminate the anadromous fish population. The reservoir would also inundate the major portion of the salmon spawning area and for this reason the fish and wildlife agencies have not recommended-a fish passage facility for this project. The 16,000 inundated acres will also eliminate wildlife habitat and at least 25 miles of stream habitat. This area is an important moose wintering range as well as a good hunting area.

19 The fluctuation associated with the 28-mile Reservoir is such that it may be adverse to the fisheries resource and biological productivity of the reservoir. Only a 50-foot strip of vegetation below the water level of the summer conservation pool would be cleared. This will leave a sub­ stantial amount of organic material to decay with the possibility of organic contamination of the water.

The 28-mile Reservoir would provide a large body of water on which to base water-oriented recreation opportunities. In addition, a 15,000-acri State park has been reserved adjacent to the project area and would serve to diversify the recreations' aspects of the Fairbanks area.

Because water supply is not a designated project purpose, the reservoir could not act as a water source without local participation funds (for increased storage capacity).

Chena River low flow augmentation for thermal and biological pollution abatement purposes could be accomplished with the 28-mile Reservoir project.

6. The Relationship Between Local Short-Term Uses of Man's Environment and the Maintenance and Enhancement of Long-Term Productivity. The recommended project will primarily result in the long-term beneficial effect of providing flood protection to the city of Fairbanks and surrounding community. The project should not degrade the utility of the environment for any foreseeable recreation use, water conservation, power development, domestic water supply, or pollution abatement. Any water-oriented recreation benefits associated with the project should be long-term in nature. As long as the project is in operation there will be a long-term potential loss of minerals, timber, and land development within the impoundment area. Construction scar3 will be minimized and short-term in nature as rehabilitation measures will be incorporated into the project requirements.

7 . Any Irreversible and Irretrievable Commitments of Resources Which Would Be Involved in the Proposed Action Should It Be Implemented. The proposed project will require the use of approximately 11,000,000 cubic yards of gravel and rock in the construction of the various project structures. Extraction of these materials will probably result in an irreversible change in the landscape and vegetation conditions that are characteristic of the borrow areas. Removal of the in-situ borrow material is irreversible. However, it is not irretrievable because the borrow material would be available for other uses if it were no longer needed in the levees and dams.

There will be an irreversible affect on the characteristic vegetation of the 2,200 acres of forest and bog habitat to be inundated. However, if the flooded area were drained it could again support terrestrial plant and animal communities. Because it is nearly impossible to restore the characteristic vegetation of the 1,000 acres occupied by the dams and levee, the commitment of vegetation should be considered irreversible. The commitment of land occupied by the nrolect structures is probably not irreversible. 8 . Coordination With Other Agencies. All interested Federal, State, and local agencies and the public have been informed of the proposed project development and afforded an opportunity to present their views during the preconstruction planning phase. The initial public meeting was on 20 October 1967 to discuss the various plans arising from emergency studies following the August 1967 flood. The meeting resulted in public acceptance of the proposed plan. The results of postauthorization analyses indicated that the 28-mile Chena River Dam and Reservoir should be replaced by a lesser structure at a downstream site. Another public meeting was held on 22 July 1971 to discuss this plan. The environmental aspects of both the original (28-mile dam) plan and the recommended modified plan were presented and discussed thoroughly at the meeting.

Press releases were issued at various times announcing the public meetings, advertising the availability of the draft environmental state­ ment, and soliciting comments thereon. Additionally, many informal meetings have been held with conservation organizations, State and Federal fish and wildlife agency representatives, and representatives of the local city and borough governments.

Comments on the draft statement covering the modified plan were requested by letter dated 9 July 1971. The transmittal letter stipulated that the draft statement would be considered satisfactory by those agencies not responding. Agency comments are summarized below. Copies of the full replies are attached to this statement.

a. Department of Natural Resources. State of AlasVs.

Comment: No objection on basic design of the project in terms of flood control. That, although the commitment of resources will be irre­ versible, the benefits in terms of recreation resources will offset such commitment.

Response: The assumption that recreation benefits will offset the irreversible commitment of resources is open to question. Recreation benefits will not offset the commitment of resources as they represent only 2 percent of the calculated benefits. Flood control and economic development administration benefits account for 98 percent of the calculated project benefits. b. Soil Conservation Service. USDA.

Comment: Generally concur with the statement. Consider the project a needed community improvement and, from an environmental standpoint, probably the best that can be conceived.

Comment: There are approximately 7 0 , 0 0 0 acres of potential agri­ cultural land located between the damsite and Fairbanks.

Response: The comment is appreciated and the information is incorporated into the final statement. Comment: Assistance offered on recommendations for revegetating disturbed areas and fills.

Response; S.C.S. assistance will be utilized.

c. Bureau of Land Management, USDI.

Comment; Waterfowl renesting attempts generally produce smaller clutch sizes and thereby reduce potential productivity.

Response; Renest clutch sizes are generally smaller but the reduction is usually not statistically significant. Of more importance is the number of ducklings fledged. The present statement has in­ corporated this information.

Comment; If inundation lasts for 1 to 2 weeks in mid-May, the most desirable nesting areas will be flooded. This would have an adverse effect on waterfowl and preclude renesting if water were held too long.

Response; The comment is valid. Additional information is in­ cluded in the present statement.

Comment; Chum and king salmon populations will be unaffected by the impoundment only if they are allowed free passage and diversion of water does not affect the smolt.

Response; Fish passage facilities are an Integral part of the project plan. Injury to migrating smolts passing through either the diversion or the passage facility is not anticipated. Each spring the south pool will be drained when flood flows subside thus not allowing fish to be detained or trapped in the pool.

Comment; The greatest edge-effect ratio is obtained with a series of streams and potholes— not with one large body of water.

Response; This is a valid comment and the present statement has been revised accordingly.

d. Alaska Power Administration. USDI.

Comment; Statement indicates that the top elevation of Chena River Dam and the 100-year flood level are both at elevation 525 feet.

Commentt Statement doesn't indicate how the dam design provides for handling the standard project flood or a maximum probable flood.

Response; Top elevation of the Chena River dam is 525 feet and the maximum probable flood is 522 feet, leaving 3 feet of freeboard. The dam is designed to handle the maximum probable flood— not the 100- year flood level, the present statement has clarified this point.

22 Comment: Adverse effects of the authorized 28-mile Chena River Dam and Reservoir seem quite extreme compared to benefits originally allocated to recreation and fish and wildlife enchancement.

Response: Recreation and fish and wildlife benefits represent 2 percent of the total project benefits. Although the adverse effects would have decreased the quality of the recreational experience, total recreation use would not have been eliminated. A more detailed discus­ sion of the alternatives has been included in the present statement.

Comment: Discussion of alternatives might also include mention of flexibility provided by the 28-mile Chena River Dam to provide low flow regulation and future water supply.

Response: The 28-mile Dam and Reservoir would have augmented flows during low flow periods. Water supply was not a project purpose of the 28-mile Reservoir and therefore no water was designated or assigned for this purpose. Additional height would have had to be added to the dam, possibly requiring additional local expense and/or reauthorization of the total project in order to store more water for supply purposes. e. Geological Survey - Water Resources Division, USDI.

Comment: Aggradation could result in the elevation of the river beds and flood plains, necessitating the raising of the dams and associated structures.

Response: If aggradation occurs, evacuation of sediment will be accomplished. Comment: Accumulation of sediments in the proposed recommended reservoir warrants discussion in the statement.

Response: The comment is valid. Little is known at this time on the sedimentation to be expected in the reservoir. The present state­ ment will be updated as new sedimentation information is obtained. Comment: Would diverted flood flows increase the discharge in the Tanana River possibly causing flooding problems downstream from the proposed dikes near Fairbanks?

Response: The Tanana River flows through a very broad flood plain in the vicinity of Fairbanks. Diversion of a high flow from the Chena into the Tanana will n^t significantly increase the water level below Fairbanks.

Comment: The impact of project construction on underlying, dis­ continuous permafrost is not mentioned.

Response: The present statement includes discussion of permafrost conditions.

23 Comment: Is there an interaction of the proposed Alyeska Trans- Alaska Pipeline with the reservoir system?

Response: The proposed pipeline alignment crosses the impound­ ment. The present statement includes discussion of the pipeline.

Comment: The Tanana and Chena River levee system is not discussed relative to its effect on the ground water regimen and effect on the existing water table.

Response: The Tanana system will be designed to keep the existing water table in approximately its present level. The present statement discusses techniques incorporated into the project plan for interior drainage and seepage collection.

f . Water Quality Office, E.P.A.

Comment: The environmental impact as well as the economic cost of the Moose Creek Dam are far less than the earlier proposed 28-mile Dam. From nearly every environmental aspect the Moose Creek Dam and Reservoir will create much less environmental degradation and the esti­ mated cost saving is $37,000,000.

Response: The present statement reflects these comments.

Comment: The small volume of the reservoir and the shallow depth should not present the water quality problems associated with the 28-mile Reservoir.

Comment: Because of the size of the Moose Creek Reservoir, manage­ ment of downstream water quality through selective discharge is not feasible as it would have been with the 28-mile Reservoir.

Response: We concur with these comments.

Comment: Adverse conditions may arise from dissolved oxygen, temperature, and pH of the Moose Creek impoundment. Dissolved oxygen is low (20 percent saturation) in the Chena River during winter months.

Response: The comment is valid; however, future investigations are intended to produce the data needed to determine the operational scheme and to minimize these adverse water quality effects.

Comment: The dissolved oxygen (D.O.) concentration will also be affected by the presence of organic material such as trees, shrubs, and mosses that will be inundated. This effect can be minimized by clearing the impoundment area down to mineral soil.

24 ' ' Response: As reported in the draft statement the north pool will be cleared, down to mineral soil. The south pool will be cleared of trees and shrubs and down to mineral soil for those areas designated as borrow material areas.

Comment: Assuming minimum winter flow of 100 c.f.s., the mean water mass residence time is 35 days for the 7,000 acre-foot north reservoir and 60 days for the 12,000 acre-foot south reservoir. This impedence of flow will lower the dissolved oxygen (D.0.) concentrations naturally occurring in the existing river.

Response: The data given are correct for the given assumptions. D.0. should be a critical factor only when the reservoir is ice-covered. The south reservoir will be drained during the winter months, thus D.0. will be a problem only in the north reservoir. Further investigations will determine D.0. levels expected in the reservoirs.

Comment: No reference is made to sedimentation in the Corps' statement.

Response: The comment is valid. Little is known at this time on the sedimentation to be expected in the reservoir. The present statement will be updated as new sedimentation information is obtained.

Comment* The impact statement elaborates on the desirable effects of the dam on fish and wildlife resources and indicates that the impound­ ment may be desirable for both grayling and northern pike. It is doubtful that both pike and grayling would permanently inhabit a reservoir of this size due to the predator/prey relationship and probable water quality condition.

Comment: High water temperature in summer will probably cause grayling to outmigrate.

Response: Scientific data on which to base a response is not available at this time. The comments cannot be evaluated until baseline data have been collected.

Comment: Waterfowl enhancement although predicted by the Corps' statement, will not occur.

Response: On a region-wide basis, the reservoir may not " contribute significantly to waterfowl production; however, waterfowl hunting could provide a significant contribution to the recreation aspects of the impoundment. Waterfowl production and hunting however, are de­ pendent on the management and operation of the reservoir.

Comment: It is not likely that waterfowl habitat will be enhanced because increased riparian vegetation and water level fluctuations may interfere with waterfowl nesting and habitat around the reservoir. 25 Response: Water fluctuation will normally be about two feet on a given year with a possible extreme fluctuation of 22 feet during a maximum flood situation. Plant species commonly associated with water- fowl habitat are usually dependent on a fluctuating water level. Depend­ ing on the management of the impoundment, waterfowl habitat could be created.

Comment: Recreational use is discussed. The proposed summer reservoir is so small in area that this recreation benefit will not be large.

Response: It is likely that total recreation boating will be less at the Moose Creek Reservoir than it would be at the 28-mile site.

Comment: The preliminary reservoir design calls for an earth sill to be constructed between the north and south pools. In addition, some type of baffle structure to assure water circulation in the north pool will be built, both structures for the purpose of maintaining water quality. The south pool would be drained at the end of the summer season to the Chena River and the north pool left as fishery habitat through the winter. Because of the doubtful ability to provide a good fishery habitat in the reservoir and the very real danger to aquatic life down­ stream, we would propose the reservoir be operated as a diversion and flow through structure.

Response: Until sufficient scientific data are available to base conclusions and recommendations on, the capabilities of the impoundment are logically questionable. Future fisheries and water quality studies will be the basis for operation.

Comment: If it was found desirable to maintain a winter pool in the reservoir, the winter flow would pass through the reservoir with a minimum reduction of dissolved oxygen. A more desirable plan would be systematically drain the reservoir after the summer recreation season in such a way as to protect the downstream water quality. This would assure no further reduction in the low (winter) D.O. levels in the lower river.

Response: A final operational scheme will be derived, based on future research information. The dam and associated works will be designed to maximize operational flexibility.

Comment: The project could be used as a basis for environmental studies relating to man's impact on the environment of the subarctic.

Response: A similar comment was made by the Alaska Conservation Society. The proposal has been discussed with persons representing the University of Alaska's Institute of Water Resources and the wildlife department, the USFS Institute of Northern Forestry and the U. S. Fish & Wildlife Service. A 1research program can be designed’to*provide the sug­ gested information.

26 g. Forest Service, USDA.

Comment: The entire Fairbanks area is in a zone of discontinuous permafrost. This may be a significant factor in dam location and relative activities.

Comment: Inundation might result in a melting action on perma­ frost which, in turn, could cause flotation of peat material from bogs.

Response: Core drilling samples along the proposed dam alignment indicate that permafrost will present no problems to dam construction. Removal of all organic material down to the mineral soil should remove any possibility of peat mats floating from the bogs in the north pool. A need for removal of floating debris from the south pool is foreseen for the initial years of the project life.

Comment: Land clearing will involve several hundreds of acres involving 500 M b.m. of merchantable timber. Provisions should be made to salvage as much of this as possible through sales.

Response: Since merchantable size timber is both scarce and valuable in the Fairbanks area, provisions will be made to salvage the merchantable timber within the proposed impoundment area.

Comment: The statement does not address itself to land ownership patterns. The possibilities of uncontrolled developments, particularly in the vicinity of the impoundment, might result in substandard private facilities.

Responses'; The Corps of Engineers will acquire all lands required for the project including a fringe area around the reservoir for recreation developments. The Corps, however, has no authority to control or plan development of private facilities located on other lands. The present environmental statement encourages the development of a land use plan for the lands adjacent to the reservoir.

Comment: Suggest you explore the idea of using borrow pits as rearing ponds for Chinook as well as other salmonlds.

Response: The fish and wildlife agencies are exploring this possibility and the Corps will act on their recommendations.

h. National Park Service, USDI.

Comment: Factual statements or implications should be documented by pertinent reference to a particular study or similar authority. Where studies are needed or are already underway to evaluate the environmental Impact, it should be so stated.

27 Response; The present statement includes a selected bibliography of references used in its preparation.

Comment: There are several places throughout the section on Environmental Impact of the Proposed Action where conflicting and question­ able statements follow one another.

Response: We have edited the statement to eliminate these conflicts.

Comment; Further elaborations could be made on plans to harvest and clear the timber prior to inundation.

Response; Harvesting and clearing proposals have been incorporated into the revised statement.

Comment; It seems appropriate that an evaluation and explanation of the placement of earthen dams in a permafrost area should be covered.

Response; Additional information on permafrost has been incorporated into the statement.

i. Fish & Wildlife Service. USDI.

Comment; Flexibility in design and operation of the project is paramount in development of a multipurpose project.

Response; With the incorporation of the recommendations of all interested agencies, a project with built-in flexibility should be accomplished.

Comment: It is imperative that adequate fish passage facilities for upstream and downstream migrations of anadromous and resident species of fish be provided at the dam site on the Chena River and at the spillway into the Tanana River.

Response; Fish passage facilities, based on design criteria obtained from the Fish & Wildlife Service, will be located at the Chena River outlet. Design of the spillway will be compatible with fish passage.

Comment; A gated water diversion structure may be required in the Chena River upstream from the maximum pool elevation to permit better control of flows into either the north pool or the Chena River to maintain suitable water quality for fish and wildlife.

Response; Studies will be made to determine the location and type of diversion construction which will provide optimum circulation pattern in the north pool.

28 Comment: The impact and influence of releasing high temperature water during the summer from the reservoir into the Chena River may have an adverse effect on anadromous and resident fish species.

Comment: Detailed water temperature and water quality studies of the Chena River w ill be required before a determination can be made as to the suitability of the pool for fishery developments.

Response: Comments are v a lid . Coordination w ill be accomplished with agencies possessing the capability of conducting water quality studies. The Corps realizes that water quality studies are paramount in determining the fishery capabilities of the two pools, downstream effects, and operational scheme of the reservoirs.

Comment: An outlet structure should be located in the main dam at the north end of the south pool to permit complete drawdown when required.

Comment: All low-lying areas in the south pool should be leveled or graded to prevent fish being trapped in "potholes."

Comment: Water and fish screening structures may be required in the berm to permit complete control of water and fis h movements between the north and south pools.

Response: The suggestions, are. appreciated. The required structures w ill be incorporated into the construction plan.

Comment: It may be possible to operate the south pool for waterfowl habitat. Building artificial islands for nesting and the establishment of appropriate types of grasses and grains on islands and shore areas would provide attractions for waterfowl. Waterfowl hunting opportunities could be enhanced.

Response: I t should be determined what the cap ability of the impoundment is and where the optimum recreation benefits e x ist. Managing the south pool for waterfowl production may not be compatible with fishery production or water recreation. If the south pool is not suitable for fishery production and/or water recreation then waterfowl production and hunting may be appropriate.

Comment: Lands within the north pool should be stripped of all vegetative materials to mineral soil or to the maximum depth possible. It may be beneficial to the fisheries to excavate mineral soil from the pool area, thus providing for a greater pool depth.

Response: A ll vegetation in the north pool w ill be stripped to mineral s o il. I t has also been concluded feasible to; extract borrow material from the impoundment area, thereby deepening-the reservoir,

29 Comment: In the event water seeps develop below the Moose Creek Dam, consideration should be given to developing these areas for salmon and grayling spawning and rearing areas, providing water temperatures and habitat features are suitable.

Response: Design features indicate that seepage w ill be collected in the drainage collection ditch negating potholes developing below the dam.

Comment: Consideration should be given to providing public access facilities for fishermen, hunters, boaters, and other recreation users.

Comment: Adequate boat passage f a c ilit ie s should be in stalled at the dam to permit recreational navigation of the Chena River.

Response: Recreation facilities (including sanitary facilities) access, and a boat passage capability are part of the overall project plan.

Comment: Continued close coordination between the Corps and fish and wildlife agencies is a key factor in the development of a compre­ hensive project.

Comment: The Corps should work closely with fish and wildlife agencies to insure that fish and wildlife resources receive adequate con­ sideration during all phases of the project.

Comment: Detailed biological, hydrological studies will be required during the planning, construction, and operational phases of the project.

Response: These comments are valid. Close coordination and detailed information are paramount at all stages in the further develop­ ment of the project and future operational scheme.

Comment: It is our view that the Chena River Lakes Project will be less damaging to fish and wildlife resources than the original Chena River Dam and Reservoir at the 28-mile site.

j. Alaska Conservation Society. Statement presented at the Public Meeting on 21 July 1971.

Comment: We believe that current project plans are far less costly, in environmental terms, than the earlier (28-mile Dam and Reservoir) proposal.

Comment: We appreciate and wholly concur with Corps' urging that it would be desirable that an environmental oriented land use plan be devised and utilized to the fullest extent in the future. The Alaska Con­ servation Society will participate with people of the community in such an endeavor. 30 Response: The comment will be included in the revised statement.

Comment• The most important complex of changes will be in water quality in afcd below the impoundment. Since the kinds of changes and their importance to aquatic life are not accurately predictable at this time, we urge that the design for construction and operation be kept as flexible as possible.

Response: Flexibility in design and operation is desirable and has been provided for.

Comment: The Chena River project should be an incentive and means to conduct studies in northern forest, bog, and river ecosystems, an ecological research effort should be planned, coordinated, and funded along with engineering aspects.

Response: One of the main construction problems in Alaska is that there are few baseline and biological data available on which to base construction criteria and plans. The Corps concurs that this project, being the first large-scale project in Interior Alaska, should serve as a basis for several investigations, providing information transferable to future projects.

Comment: We seriously doubt that the overall effect of the project on waterfowl will be favorable, or even measurable.

Response: Waterfowl production in the impoundment area, when compared regionally, may not contribute significantly to the overall population.

Comment: We are not as ready as the Corps is to accept the idea that organic debris generated in the impoundment will be aaslly disposed of. It seems that suspended, rooted, and floating debris will create recreational and biologic problems for many years after the dam is built.

Response: Efforts will be made to clear as much of the impoundment area to mineral soil as is possible. The reservoir water surface will be cleaned of floating debris throughout the recreation season. This subject is discussed in depth in the present statement.

Comment: Alleged fishery benefits seem a bit contrived.

Response: Lack of specific fisheries data on which to base the benefit derivation required making certain assumptions. These may be found erroneous when factual data become available; however, contrivance or intent to deceive are denied.

31 Comment: We are also concerned that at this time many project features are left for future determination and solution— specifically wildlife mitigation. We want to be assured that fiscal authorizations include enough money to take care of these future costs.

Response: Funds specifically earmarked for fish and wildlife mitigation have been included in requests for future appropriations.

Comment: The Alaska Conservation Society is in favor of the project substantially as proposed in the impact statement of 9 July 1971. We think the Corps has suggested a plan that will cause as little dis­ turbance to the normal water flows and ecologic processes as possible.

k. Bureau of Outdoor Recreation, USDI.

Comment: Generally find the draft statement to be a comprehensive assessment of the environmental impact of the project.

Comment: It would be advantageous to expand on the environmental aspects of the "indirect" impact to strengthen the justification and need for comprehensive flood plain planning and management.

Response: Additional information will be included in the statement.

Comment: It would be helpful if the statement could address some of the environmental impacts of the recreation features of the project.

Response: Although difficult to project recreational impact, the revised statement will include an assessment of the probable impacts.

Comment: The operation characteristics of the Moose Creek Reservoir may present some environmental problems in achieving the full realization of the recreation potential.

Response: Some inherent characteristics of the Chena River Reservoir may preclude some recreational opportunities. Compatible recreation activities will be developed.

Comment: The statement alludes to the possibility of converting borrow areas into trailer camping areas. Although this is a possibility our experience is that the conversion of material sites is usually a less desirable alternative as opposed to properly designed and strategically located camping areas.

Response: The borrow pit/camping areas are not intended to replace any "properly designed or strategically located" camping areas. They are suggested as overflow areas for the choice sites. Although the material requirement may dictate differently, borrow sites could be located in areas which would be desirable camping areas as well. 32 Comment; There may be an additional nonstructural alternative involving a combination nonstructural method of achieving flood protection.

„ Response. This combination" alternative will be discussed in the final statement.

Comment; While it is true that pool fluctuations of the 28-mile Reservoir would impose some limitations on its recreation potential, there are large flood control reservoirs which are heavily utilized for outdoor recreation.

Comment; The 28-mile Reservoir would have a much larger pool available for recreation use during the summer months (although subject to fluctuation) and perhaps more importantly, it would complement the existing Chena River Recreation Area through diversification of recreation opportunities available.

Response; We concur with the comments; however, when the total environmental effects of the 28-mile Reservoir are studied, the reservoir is not as desirable.

Comment: At this stage of planning it is uncertain that the Moose Creek Reservoir will generate a level of recreation benefits comparable to the 28-mile Reservoir or if indeed there will be a non-Federal sponsor to permit recreation development under the provisions of PL 89-72.

Response; The comment is valid. The Bureau of Outdoor Recreation will evaluate the recreation benefits of the Chena River Reservoir.

statements were sent to the following with no response received: Office of the Governor; State Departments of Public Works, Highways, Health & Welfare, and Economic Development; Bureau of Indian Affairs; Fairbanks Chapters of the Sierra Club and Friends of the Earth; Alaska Wildlife Federation; Trout Unlimited; the Izaak Walton League; and the Tanana Valley Sportmen's Association. The Alaska Department of Fish and Game requested and was granted a time extension in which to reply. To provide a current summary, copies of the final statement will be sent to all known individuals and organizations originally contacted. The final statement will be updated as new information become available. SELECTED BIBLIOGRAPHY

Corps of Engineers. 1967. FLOOD PLAIN INFORMATION, CHENA RIVER, FAIRBANKS, ALASKA. U.S. Army, Alaska District.

Corps of Engineers. 1967. REVIEW OF REPORTS ON TANANA RIVER BASIN, FAIRBANKS, ALASKA. U.S. Army, Alaska District.

Corps of Engineers. 1971. POST“AUTHORIZATION REPORT, CHENA RIVER LAKES PROJECT, FAIRBANKS, ALASKA. Alaska District, U. S. Army.

Dingman, S. L., H. R. Samide, D. L. Saboe, M. J. Lynch and C. W. Slaughter. 1971. HYDROLOGIC RECONNAISSANCE OF THE DELTA RIVER AND ITS DRAINAGE BASIN, ALASKA. Cold Region Research and Engineer­ ing Laboratory; Research Report 262.

Frey, J. P., E. W. Mueller, and E. C. Berry. 1970. THE CHENA RIVER - THE STUDY OF A SUBARCTIC STREAM. Federal Water Quality Administra­ tion, Alaska Water Laboratory, Project Report No. 1610.

Hooper, D. C. 1952. WATERFOWL INVESTIGATIONS AT MINTO LAKES, ALASKA. M.S. Thesis, University of Alaska.

Johnson, Philip L., and Theodore C. Vogel. 1966. VEGETATION OF THE YUKON FLATS REGION, ALASKA. Cold Region Research & Engineering Laboratory; Research Report 209.

Johnson, P. R. and C. W. Hartman. 1969. ENVIRONMENTAL ATLAS OF ALASKA. Inst, of Arctic Environmental Engineering and Inst, of Water Resources, University of Alaska

Kimai, Motoi and Harold W. O'Brien. 1965. A STUDY OF ICE FOG AND ICE-FOG NUCLEI AT FAIRBANKS, ALASKA, PART II. Cold Region Research & Engineering Laboratory; Research Report 150.

Kogl, D. R. 1965. SPRINGS AND GROUND-WATER AS FACTORS AFFECTING SURVIVAL OF CHUM SALMON SPAWN IN A SUBARCTIC STREAM. M.S. Thesis, University of Alaska.

Krenkel, P. A. and F. L. Parker. 1969. BIOLOGICAL ASPECTS OF THERMAL POLLUTION. Proceedings of the Nat. Sym. on Thermal Pollution.

Likens, Gene E., and Philip L. Johnson. 1968. A LIMNOLOGICAL RECON­ NAISSANCE IN INTERIOR ALASKA. Cold Region Research & Engineering Laboratory; Research Report 239.

MacKenthun, K. M. 1969. THE PRACTICE OF WATER POLLUTION BIOLOGY. USDI, Federal Water Pollution Control Administration. Rowinski, Ludwig J. 1958. A REVIEW OF WATERFOWL INVESTIGATIONS AND A COMPARISON OF AERIAL AND GROUND CENSUSING OF WATERFOWL AT MINTO FLATS, ALASKA. M.S. Thesis, University of Alaska.

Schallock, E. W. 1966. GRAYLING LIFE HISTORY RELATED TO A HYDRO­ ELECTRIC DEVELOPMENT ON THE CHATANIKA RIVER IN INTERIOR ALASKA. M.S. Thesis, University of Alaska.

University of Alaska. 1970. FAIRBANKS: AN ECONOMIC PROFILE. Review of Business and Economic Conditions, Vol. VII, No. 1.

Vascotto, G. L. 1970. SUMMER ECOLOGY AND BEHAVIOR OF THE GRAYLING OF MCMANUS CREEK, ALASKA. M.S. Thesis, University of Alaska.

Wilde, S. A., and H. H. Krause. 1960. SOIL— FOREST TYPES OF THE YUKON AND TANANA VALLEYS IN SUBARCTIC ALASKA. Journal of Soil Science, Vol. 11, No. 2

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July 13, 1971

A. C. Mathews Colonel, Corps of Engineers District Engineer P. 0. Box 7002 Anchorage, Alaska 99501

Re: (1130-2-1) Chena River Lakes project

Dear Colonel Mathews:

We have reviewed the draft of the environmental impact statement and in doing so, the following comments have been generated:

- That we have no objection to the basic design in terms of flood control;

- That although the commitment of resources will be irreversible, the benefits in terms of recreation resources above will off-set such commitment•

Sincerely yours,

EDWARD J. KRAMER, Acting Director

By: G. Robert Scott Parks Designer UNITED STATES DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE P. 0. Box F, Palmer, Alaska 99645

August 6, 1971

Colonel A. C. Mathews Corps of Engineers District Engineer P. 0. Box 7002 Anchorage, Alaska 99510

Dear Colonel Mathews:

We have reviewed your draft Environmental Impact Statement for the Chena River Lakes Flood Control Project, Fairbanks, Alaska, and have only one minor comment for your consideration. On page six, bottom of the page, where you discuss the agricultural development in the Chena and Tanana River Basins, our information shows that there are approximately 70,000 acres of potential agricultural land located in the area beginning just below the Chena River Dam Site and bounded by the community of North Pole and the general area of Fairbanks at the downstream extremities.

The soils in this area vary from Class II to Class IV soils. The soils classified as Class IV are interspersed throughout the area and are so classified because of their wetness. As you described, this area has been developed to a limited extent, however, increased acreages will be utilized in the future for agricultural production to meet local market needs.

Our local representative, in reviewing the statement, believes that you have covered the subject quite well. We believe the proposed plan from the environmental standpoint is probably the best that can be conceived and is certainly needed by the community.

If we can be of assistance in giving recommendations for revegetating disturbed areas and fills, we will be happy to do so. We appreciate the opportunity to review the draft and to comment previously on the proposed plan.

Sincerely,

Weymeth E. Long State Conservationist

cc: B. Clifford U nited States Departm ent o f the Interior 1791 (9ii)

bureau o f l a n d m a n a g e m e n t Your reference: State Office NPAEN-PR-R 555 Cordova Street Anchorage, Alaska 99501 August 5, 1971

Colonel A. C. Mathews District Engineer Alaska District, Corps of Engineers P.O. Box 7002 Anchorage, Alaska 99510

Dear Colonel Mathews: We have reviewed your draft Environmental Impact Statement for the Chena River Lakes Flood Control Project, Fairbanks, and have the following to offer for your consideration:

1. Page ll--top: The greatest edge-effect ratio is obtained with a series of streams and potholes, and not with one large body of water. The amount of open water will increase, but the shoreline footage will probably decrease. With less edge there will likely be less fur bearers and less waterfowl.

2. Page ll--bottom: Renesting attempts generally produce smaller clutch sizes and thereby reduce potential productivity.

3. Page 12--bottom: "The chum and king salmon populations will be unaffected by the impoundment" only if passage is accomplished and if the diversion of water does not affect the smolt.

4. Page 16--middle: If inundation lasts for 1-2 weeks in mid-May, the most desirable nesting areas will be flooded. This would have an adverse effect on waterfowl, and may even preclude re-nesting if the impounded water is held too long.

5. Page 20--top: See previous comments.

6. Page 24: We note that the North Star Borough, Fairbanks and North Pole City governments have not been coordinated with this project and suggest that perhaps they should be.

We hope these conments are helpful as you finalize your impact statement. Sincerely yours,

Acting State director United States Department of the Interior ALASKA POWER ADMINISTRATION P O BOX 50 JUNEAU ALASKA 9980)

July 30, 1971

AIRMAIL

Colonel A. C. Mathews D is tric t Engineer Alaska D is tric t, Corps o f Engineers Box 7002 Anchorage, Alaska 99510

Dear Colonel Mathews:

This is in response to your July 9, 1971 le tte r in v itin g corrcients on your Draft Environmental Impact Statement for the Chena River Lakes Flood Control Project, Fairbanks, Alaska.

We appreciate the opportunity to provide informal comments on your draft statement and the courtesy o f Lt. Wold's recent v is it to th is o ffice concerning the statement. We do not have the details on your r.ew plan, except for the lim ited data presented in your statement and the supple­ mental explanations Lt. Wold could offer from his position as drafter of the environmental statement. Our consents, therefore, are necessarily quite general. They are offered for your consideration in connection with the revisions o f the statement which our discussions with Lt. Wold indicated may be appropriate.

We note a seeming change in design criteria and levels of flood protection between the Chena River Dam (Mile 28 Dam) and the Moose Creek Dam, which may merit clarification.

S.D. 89, 90th Congress, Second Session, at pages 18, 21 and 27, indicates that the Chena River Dam, together with the other project features, would reduce the Standard Project Flood (frequency of about 170 years) to channel capacity through Fairbanks and that the dam it s e lf would be designed to pass a maximum probable flood.

Pages 1 and 2 of the draft environmental statement state that the top elevation of the Moose Creek Dam and the 100-year flood level at the dam are both at elevation 825 feet. The statement doesn't indicate how the Moose Creek Dam design provides fo r handling the Standard Project Flood or a maximum probable flood, or the level of flood protection provided through Fairbanks. The discussion of adverse effects of the Chena River Dam (Mile 28 Dam) on pages 21 and 22 o f your statement seems quite extreme when compared with the favorable findings and assignment of benefits and allocations of costs to recreation and fish and w ild life purposes in S.D. 89. It is our understanding that better definition of the specific fish and w ildlife and recreation benefits assignable to the Moose Creek dams and reservoirs has been in itia te d .

The discussion of alternatives might also include mention of fle xib ility provided by the Chena River (Mile 28) Dam to provide low flow regulation through Fairbanks. Although not s p e c ific a lly included as a project purpose in S.D. 89, th is fle x ib ilit y would seem o f considerable value to Fairbanks and a possible factor in long range water supply planning for the area.

We note with pleasure the favorable economic justification for your new plan and we look forward to further progress on this urgently needed project.

We would appreciate receiving a copy of your revised statement when it is available.

Sincerely,

Robert W. Ward Administrator cc: Asst. Secretary, Water & Power Resources UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY Water Resources Division 218 E Street - Skyline Bldg. Anchorage, Alaska 99501

August 6, 1971

A. C. Mathews Colonel, Corps of Engineers D is tric t Engineer P. 0. Box 7002 Anchorage, Alaska 99510

Dear Colonel Mathews:

In accordance with the provisions o f the National Environmental Policy Act and your request to review and coircnent on the Draft Environmental Impact Statement fo r the Chena River Lakes Flood Control Project, Fairbanks, Alaska, the Alaska District Office offers the following remarks or questions which you may wish to consider 1n the preparation of your fin a l Statement.

1. The fact that the Chena and the Tanana Rivers are aggrading riv e r systems is not mentioned in the Impact Statement. Aggradation could result in the elevation of the river beds and flood plains. This could neces­ sitate the raising o f the dams, the outlet structures, or the dikes. The long term effect of the reduction in deposition in the Chena basin by control of flooding would be to increase the difference in altitude of the Tanana River flood plain relative to the Chena flood plain upon which the City of Fairbanks is located. Also, perhaps the accumulation of sediments 1n the proposed reservoirs would warrant some discussion.

2. Would the flood-flow increase 1n discharge in the Tanana River at Moose Creek Bluffs possibly cause flooding problems downstream from the proposed dikes near Fairbanks? This would also warrant discussion.

3. The interaction or impact of dam construction, impoundments and dikes on the underlying discontinuous permafrost terrain is not mentioned. The desirability of a continuing surveillance and maintenance program in permafrost also is not discussed. August 6, 1971

4. We note the intersection of the proposed Aleyska Trans- Alaska Pipeline with the northern reservoir of the Moose Creek reservoir system. The possible effects of the pipe­ lin e on the proposed flood control project and the environ­ ment require discussion. What are the possible effects on foundations, slope stability, and water quality?

5. The Tanana and Chena River levee system is not discussed relative to its effect on the ground water regimen of the area and its e ffe ct on the existing water tables.

The foregoing couments are provided informally for technical assistance and are not intended to represent the position of the Department o f the Interior.

Sincerely yours,

Harry Hulking District Chief ENVIRONMENTAL PROTECTION AGENCY

WATER QUALITY OFFICE ALASKA OPERATIONS DM 9, FEOEKAl IUIIDIXC KOI F OUKTH AVENUE ANCNORAfiE. ALASKA 00501

Augus t 3, 1971

Colonel A. C. Matthews District Engineer Department of the Army Alaska District, Corps of Engineers P. 0. Box 7002 Anchorage, Alaska 99501

Re: NPAEN-PR-R Chena River Flood Control Project

Dear Colonel Matthews:

The public meeting on July 21, 1971 regarding the Chena River Flood Control Project was attended by Mr. Richard Latimer, Director of the Alaska Water Laboratory and members of his staff. A report was written in memorandum form which, because of its completeness and detail, is herewith forwarded for your use.

We would like to express our appreciation for this opportunity to work with the Corps of Engineers on the Chena River Flood Control Project, and we look forward to additional involvement as this project further develops.

Please advise if we can be of further assistance.

Sincerely yours,

Stanley Bi'ust Federal Activities Coordinator ENVIRONMENTAL PROTECTION AGENCY

WATER QUALITY OFFICE

ALASKA WATER LABORATORY COLLEGE. ALASKA 99701

JUL 28 1971

MEMORANDUM

TO: Director, Alaska Operations Office Anchorage, Alaska

FROM: Director, Alaska Water Laboratory College, Alaska

SUBJECT: Chena River Flood Control Project

A public meeting covering the Flood Control Project was held in Fairbanks July 21, 1971. In addition to the public meeting there was an informal afternoon meeting with the Corps of Engineers Environmentalist at the University that was attended by several local conservation representatives. Messrs. Mueller, Schallock and Latimer attended these meetings.

The general feeling of nearly a ll who commented and testified at the meetings was that the current proposal was much more desirable than the 28-mile plan. There was essentially no opposition to the proposed change. Both the Alaska Conservation Society and the Tanana Valley Sportsman's Association were generally in favor o f the project as currently proposed. The State Fish | and Game and the Bureau o f Sport Fisheries and W ild life made l i t t l e commentj except that it was an improvement over the 28-mile plan. They w ill both submit w ritten statements with sp e cific recommendations.

The presentation made by the Corps and the drawings available for review were essentially a conceptual design. Very few firm numbers were available and the Corps at this point in time is s till developing design data. This makes the Draft Environmental Statement and the project design and operation plan d if f ic u lt to review. Because of the unique environmental setting of this project, there is little information which is directly applicable to an evaluation of environmental impact. However, we have s u ffic ie n t experience with the Chena River to be able to predict some possible effects of the pro­ posed impoundment on the riv e r and associated environment.

The environmental impact as well as the economic cost of the Moose Creek dam are fa r less than the e a rlie r proposed 28-mile dam. From nearly every environmental aspect the Moose Creek dam w ill create much less environmental degradation and the estimated cost saving Is $37,000,000. • Director, Alaska Operations Office -2- July 28, 1971

The small volume (7,000 - 12,000 acre feet) of the reservoir and the shallow depth (5 - 15 feet) should not present the water quality problems o f the 28-mile dam. However, because of the size o f the lower reservoir, manage­ ment of downstream water quality through selective discharge is not feasible as i t would be in a larger impoundment.

Several critical water quality parameters could be affected by the Moose Creek dam and impoundment. Dissolved oxygen, temperature, and pH may be adversely affected, depending on reservoir operation. Dissolved oxygen 1s low in the Chena River during the winter reaching levels less than 20% saturation. Data from recent AWL studies suggest that the longer the water is retained in the system, the lower the D.0. concentration falls. Creation of an impoundment would significantly increase the period of time that is required for a water mass to travel through the system.

U tiliz in g Corps of Engineers area and average depth values, impoundment volumes of 7,000 acre feet for the north reservoir and 12,000 acre feet for the combined north and south reservoir were calculated. Assuming minimum winter flow of 100 cfs in that area the mean water mass residence time is 35 days for the 7,000 acre foot reservoir and 60 days for the 12,000 acre foot reservoir. This impedence of flow w ill lower the 0.0. concentrations naturally occuring in the existing river.

The D.0. concentration w ill also be affected by the presence of any organic material such as trees, shrubs, mosses, etc., that are inundated by the reservoir. This effect can be minimized by clearing down to mineral soil a ll of the organic material within the proposed summer Impoundment area. River water temperature below the impoundment w ill also be affected. The reservoir during summer operation w ill add heat to the system increasing the peak temperature and lengthening the period of high water temperatures.

Other parameters that w ill be affected w ill be pH and a lk a lin ity . The pH w ill probably become more acidic due to humic and fluvic acid. Duirnal' fluctuations may be broad because of photosynthetic activity within the impoundment. Alkalinity may be increased due to increased dissolved bicarbonate, carbonate and hydroxide components of the water.

Sediment is also a consideration. No reference is made to sedimentation in the Corps of Engineers environmental Impact statement. However, formation of an impoundment w ill indeed settle suspended material out of the river thus in some measure increasing the water quality of the down­ stream waters. Consideration must be made for the deposition that w ill occur in the impoundment. Material that enters the reservoir w ill cover the bottom thickly in some areas and thinly in others depending upon the bottom configuration and the current pattern. If deposits of organic material are covered by s i l t , aerobic processes w ill not be able to proceed and w ill ultimately be replaced by undesirable anaerobic processes. Deposition around the outlet structure may interfere with its operation and necessitate slug loadings of s ilt through the outlet works to keep the system flushed. The impact statement elaborates on the desirable effects of the dam on fis h and w ild life resources and indicates that the impoundment may be - desirable for both grayling and northern pike. It is doubtful that both pike and grayling would permanently inhabit a reservoir of th is size due to the predator-prey relationships and probable water quality conditions. High water temperature in summer w ill probably cause the grayling to outmigrate. Low D.O. in the winter would cause the fish to congregate in. waters with higher D.O. Waterfowl enhancement, although predicted by the Corps of Engineers report, w ill probaoly not occur. It is not likely that waterflow habitat w ill be enhanced because of increased riparian vegetation and water level fluctuations may interfere with waterfowl nesting and habitat around the reservoir.

Recreational use of the area is discussed. This includes boating, water skiing, swimming, fish in g, camping, and picnicing. However, the proposed summer reservoir is so small in area that this recreational benefit w ill not be large.

The preliminary reservoir design and operation plan calls for an earth s ill to be constructed between the north and south pools. In addition some type of baffle structure to assure water circulation in the north pool will be b u ilt, both structures fo r the purpose of maintaining water quality, in part o f the reservoir as well as down stream from the impoundment. The south pool would be drained at the end of the summer season to the Chena River and the north pool le ft as fishery habitat through the winter.

We feel this concept is not valid for the several reasons previously mentioned. Because of the doubtful a b ilit y to provide a good fishery habitat in the reservoir and the very real danger to aquatic life downstream we would propose the reservoir be operated as a diversion and flow through structure. This would eliminate the need for both the s ill and the baffle structures. Water flowing into the reservoir during the spring and summer would with l i t t l e mixing tend to flow through the short reservoir and outlet works with a minimum o f warming thus protecting the downstream cold water habitat.

If it was found desirable to maintain a winter pool in the reservoir, the winter flow would likewise pass tnrough the reservoir with a minimum reduction of dissolved oxygen. A more desirable plan would be to system­ a t ic a lly drain the reservoir after the summer recreation season in such a way as to protect the downstream water quality. This would assure no further reduction in the existing low winter dissolved oxygen levels ir. the lower riv e r. In any event the dam and appurtenant works should be designed with operational flexability in mind in order to maximize water quality and other environmental considerations.

The entire project could be used as a basis for environmental studies relating to man's impact on the environment of the subarctic. Such studies if provided for by the project would assure the support of conservationists as well as provide EPA with a valuable laboratory for some vitally needed environmental studies.

If we can provide further information please advise.

Richard W. Latimer cc • E. W. Mueller E. U. Schallock U n i t e d S t a t e s D e p a r t m e n t o f A g r i c u l t u r e FOREST SERVICE P.0. Box 1628, Juneau, Alaska 99801

August 5, 1971

1530 1940 district Engineer Alaska District Corps of Engineers P.O. Box 7002 Anchorage, Alaska 99510 Your ref: NPAEN-PR-R of 7/9

Dear Sir:

This is in response to your request for comments on the draft environ­ mental statement developed for the Chena River Lakes Flood Control Project near Fairbanks, Alaska.

The draft statement appears comprehensive and you are commended for your obvious in-depth analysis of impacts and for the development of possible prescriptive mitigation considerations.

We offer the following for your consideration and possible incorporation into the final environmental statement as well as into project plans.

1. The entire Fairbanks area is in a zone of discontinuous permafrost. This may be a significant factor in dam location and related activities. Flooding might result in a melting action on permafrost which, in turn, could cause flotation of islands of peat material from bogs. This could result in a maintenance problem.

2. Land clearing will involve several hundreds of acres involving 500 MBF of merchantable timber. Provisions should be made to salvage as much of this as possible through sales to local operators.

In addition, slash disposal might involve the use of fire. Adequate protection in disposal of clearing slash should be provided.

3. The draft does not address itself to land ownership patterns. The possibilities of uncontrolled developments, particularly in the vicinity of the Moose Creek reservoirs, might result in substandard private facilities with attendant access, sanitation, pollution, and aesthetic problems. Provisions should be made through zoning, or acquisition to assure public use, protection and orderly development of shoreline areas. 2

4. An undetermined amount of fill material will require the development of several dryland borrow pits. Although the statement mentions screening and other rehabilitative measures* we suggest you explore the possibility of using borrow pits as rearing ponds for chinook as well as other salmonids. This has been successful in other areas.

5. P.L. 91-664 mentioned on page 10 should read P.L. 91-646.

We appreciate the opportunity to conment on your draft statement and look forward to receiving the formal draft after its submission to the Council on Environmental Quality.

Sincerely,

C. A. YATpS Regional Forester United States Departm ent of the Interior

NATIONAL PARK SERVICE Pacific Northwest Region 931 Fourth and Pike Building Seattle, Washington 98101

August 10, 1971

Colonel A. C. Mathews D istrict Engineer U.S, Army Engineer D istrict, Alaska P.O. Box 7002 Anchorage, Alaska 99501

Dear Colonel Mathews:

We have reviewed your draft of the environmental impact statement, Chena River Lakes Flood Control Project, Fairbanks, Alaska.

We believe that the statement can be improved considerably by docu­ menting your supporting information and rewording or deletion of some sentences that appear to cause ambiguity or co n flict with some thoughts.

In the first instance, there is an example on page 13 where you state that inundation of the Chena River will make the marsh area advanta­ geous to wildlife and Fairbanks residents alike. Such factual state­ ments or implications should be documented by pertinent reference to a particular study or similar authority. If, in fact, this is only an opinion, it should be stated as such. Where studies are needed or are already underway to evaluate the environmental impact, this also should be noted.

In the second instance, as mentioned above, there are several places throughout the section on Environmental Impact of the Proposed Action where conflicting and questionable statements follow one another. In most of these situations, it appears that recasting or deletion of wording can give greater strength and clarity to the statement. This does not imply that negative points should not be emphasized, but they should appear in proper perspective and context. For example, on page 14, it is mentioned that this impoundment (reservoir) will have an effect upon plants and animals involved. Further, it is stated that although physical, biological, chemical changes, and organic contamination will occur in the reservoir, these conditions should not be problems. However, in the preceding paragraph on the bottom of page 13, it is stated that plankton blooms could make the area less desirable for water recreation. It seems that here the statement can be strengthened and clarified as follows: "Although there will be some ecological changes in the reservoir ecosystem, such as plankton bloom and organic contamination from inundated stands of timber, these conditions are considered to be minor and controllable within present knowledge of resources management."

Further elaborations could be made on plans to harvest and clear the present forest prior to inundation, etc.

It seems appropriate that an evaluation and explanation of the place­ ment of earthen dams in a permafrost area should be made. Conserva­ tionists are keenly aware of this impact on arctic ecosystems.

Thank you for the opportunity to review the environmental statement.

Sincerely yours,

Bennett T. Gale Acting Director cc: Council on Environmental Quality (10) U nited States Departm ent o f the Interior FISH AND WILDLIFE SERVICE BUREAU OP SPORT FISHERIES AND WILDLIFE 6917 Seward. Highway Anchorage, Alaska 99502

August 9» 1971

District Engineer U. S. Army Engineer District Alaska Corps of Engineers P. 0. Box 7002 Anchorage, Alaska 99501

Dear Sir:

Reference is made to your letter of July 8, 1971* requesting the comments of the U. S. Fish and Wildlife Service on the revised authorized Chena River Lakes Project. These are our preliminary comments on the revised portion of the proposed project and do not constitute our detailed report as authorized by the Fish and Wildlife Coordination Act (1*8 Stat. U01, as amended: 16 U.S.C. 66 et. seq.). Reconmendations for fish and wildlife are as detailed as is possible at the present stage of project planning and are based on engineering information provided in your letters of July 18 and July 19* 1971» and. at conferences between our agencies.

We have incorporated our comments and recommendations on both the Draft Environmental Statement and your preliminary design of Chena River Lakes Flood Control Project as referenced in your letter of July 19, 1971. This letter has been reviewed by the Alaska Department of Fish and Game. A copy of their comments will be provided at a later date. National Marine Fisheries Service, Department of Commerce, will provide separate comments.

The proposed Moose Creek Project would be located on the Chena River about 17 air miles east of Fairbanks. It would consist of an earth- fill dam averaging about 30 feet in height, 2k feet wide, with a top elevation of 525 (m.s.l.). It would extend from the reconstructed Moose Creek dike northward for 7.1 miles to a hill north of the Chena River. This dam would divert flood flows from the Chena River into the Tanana River. It would create two reservoirs separated by an impervious rock-faced overflow sill. The sill, with a top elevation of 500 feet (m.s.l.) will be located about midway along the dam and - 2 - will extend eastward (about 2,500 feet) from the dam until the top intersects natural ground at elevation 500 feet (m.s.l.). The north pool will cover an area of about 700 acres and will have a maximum depth of about 15 feet, while the south pool will cover about 1,700 acres and will have a pool depth varying from 5 to 10 feet. During an extreme maximum flood stage (elevation 525 feet), occurring about once every 100 years, the reservoir could cover up to 10,000 surface acres and have a maximum volume of 200,000 acre-feet for about a two- week duration. There would be a water control structure at the Chena River dam and one at the south pool overspill structure into the Tanana River. Additionally, there would be a drainage channel connecting the south pool and the reservoir seepage with the Chena River.

Detailed reservoir operation plans have not been developed; however, it is assumed that a wide range of flexibility will be designed into the operation plans to permit complete control of storage space in the combined reservoirs as well as flow in the Chena River. Fish passage facilities will be located at the Chena River dam and at the Moose Creek dike. During flood stages, the outlet works and channel will provide access and passage for migratory fish species coming from the Tanana River. The outlet works on the Chena River, designed to allow a maximum downstream release of 6,000 c.f.s., would include debris racks, control gates, and energy dissipaters. A public access road about five miles long would connect the Chena Hot Springs Road and the project area.

Fish and wildlife resources within the area of influence of the project area are essentially the same as those outlined in our report dated October 13, 19 6 7 . Therefore, additional comments on the fish and wildlife resources in the area will be withheld until completion of ongoing and proposed fish, wildlife, and other related studies.

Flexibility in design and operation of the project is paramount in development of a multipurpose project that will provide flood protection to the City of Fairbanks, preserve natural resources, provide recreation, and mitigate losses that may occur within the area of influence of the project. Enhancement of fish and wildlife resources and water oriented recreational potential should also be considered. Water control structures and facilities that would permit complete regulatory control and circulation of stream flows within impounded waters would be required to realize maximum fish, wildlife, and recreational potential from project development. The project operation should be based on the needs of all interested local, state, and federal agencies participating with the Corps of Engineers as lead agency.

It is imperative that adequate fish passage facilities for upstream and downstream migrations of anadromous and resident species of fish be provided at the Moose Creek site on the Chena River and at the - 3- spillway into the Tanana River. A gated water diversion structure may be required in the Chena River upstream from the maximum pool elevation to permit complete control of flows into either the north pool or the Chena River to maintain suitable water quality for fish and wildlife. Facilities should be designed with a capability of retaining the entire flow of the Chena River in the existing channel or diverting the flow into the north reservoir. Gated control structures should be provided in the spillway structure into the Tanana River to permit complete water control in the south reservoir.

The berm separating the proposed north and south pools should be located in such a manner as to provide the greatest possible depth of water in the north pool for fish use. It may be feasible to develop and manage the north pool for a year around sport fishery. However, detailed water temperature and water quality studies of the Chena River and proposed reservoirs, will be required before a determination can be made as to the suitability of the pool for fishery developments. Additionally, the impact and influence of releasing high temperature water during the summer from the reservoir into the Chena River below the dam, may have adverse effect on anadromous and resident species of fish. Water control and fish screening structures may be required in the berm to permit complete control of water and fish movements between the north pool and the south pool. In addition, an outlet structure should be located in the main dam at the north end of the south pool to permit complete drawdown when required. All low-lying areas in the south pool should be leveled or graded and connected with channels to prevent water pooling which could trap fish.

It may be possible to develop and operate the south pool for waterfowl habitat. This could be accomplished by building artificial islands for nesting throughout the area. Materials cleared from within the reservoir takeline could be utilized for construction purposes. Establishment of appropriate types of grasses and cereal grains, on the islands and shoal areas, would provide adequate feed for attracting both spring and fall migrations of waterfowl which could provide waterfowl hunting opportunities during the fall season.

Lands within the proposed north pool should be stripped of all vegetative materials to mineral soil or to the maximum depth possible which would permit drainage. In fact, it may be beneficial to the fisheries and feasible from an engineering standpoint, to excavate mineral soil from the pool area, thus providing greater depth to the proposed permanent pool.

In the event ground water seeps develop below the Moose Creek dam, consideration should be given to developing these areas for salmon and grayling spawning and rearing areas providing water temperatures and other habitat features are suitable. It may be feasible to design a water supply system either from the reservoir or from ground water to -U

supplement seep flows and provide enhancement of both anadramous and resident fish production in the seep areas. If water temperatures of the seep waters are unsuitable for fish use this channel m ay need to flow into the Tanana River in order to protect the Chena River fisheries.

Consideration should be given to providing public access facilities for fishermen, hunters, boaters, and other water oriented recreation users.

Adequate boat passage facilities should be installed at the dam to permit recreational navigation of the Chena River.

The Corps of Engineers should work closely with the Bureau of Sport Fisheries and Wildlife, Alaska Department of Fish and Game, and National Marine Fisheries Service in the development of detailed plans for the project to assure that fish and wildlife resources receive adequate consideration during the planning, construction, and operational stages of the project. Detailed biological, hydrological and thermal studies will be required during the planning, construction and operational phases of the project. Adequate funding must be provided by the Corps of Engineers before the necessary studies can be undertaken.

The above comments have been discussed and reviewed with members of your staff, National Marine Fisheries Service, Alaska Department of Fish and Game, and local Fairbanks agencies. Until detailed project plans are developed, we cannot provide specific recommendations. However, incorporation of the maximum degree of flexibility into the project design, construction, and operation would be highly desirable from the fish and wildlife standpoint.

Continued close coordination between the Corps of Engineers, Bureau of Sport Fisheries and Wildlife, and other Federal and State agencies is a key factor in development of a comprehensive project. Therefore, it is requested that we be apprised of changes in project design as they develop.

We appreciate the opportunity to participate in the planning stages for development of this project. It is our view that the Chena River Lakes Project will be less damagirg to fish and wildlife resources than the original Chena River Dam and Reservoir at the 28 mile site.

Sincerely,

Area Director Statement of the Alaska Conservation Society

Environmental Impact Hearings

Chena River Flood Control Project

Fairbanks July 21, 1 9 7 1

Mr. Chairman, the Alaska Conservation Society requests that the

following statement be made a part of the official record of the

public hearing on the Chena River L*kes Flood Control Project by

the U.S. Corps of Engineers. We are pleased to be able to testify

in favor of the project substantially as proposed in the July 9

impact statement. We believe that current project plans are far

less costly , in environmental and economic terms, than the earlier

proposal.

People who live in Fairbanks will readily agree that in many res­

pects the site for the city, now a much bigger town than foreseen

by the first miners and river tradesmen who established it, is not

the best available. Several severe environmental problems beset

the city that could not have been avoided if facts we now have had

been known and applied to selection of the townsite. Groundwater

quality problems, serious air pollution problems, and rather frequent

threats of flooding are the most obvious.

More than once, in a session of the grand old American game of

Monday - morning quaterbacking, we have discussed other possible sites

for the city and half seriously wondered how much it would cost to

move Fairbanks to high ground. Our conclusion, of course, is the same as that expressed by the Corps of Engineers in the present environ­ mental statement.- the town has outgrown the age when it might have been possible to move. Still, we do appreciate and wholly concur with the Corps' urging (page 10) that "...it would be desirable that an environmentally oriented land use plan (be) devised and utilized in the future to the fullest extent." Several members of the Alaska Conserva­ tion Society stand ready to participate with other people of the community in such an endeavor, ameliorating many present hardships, dangers and inconveniences to those who live on the Chena floodplain.

The Corps of Engineers is to be complimented on its efforts to describe and evaluate the many ecologic and environmental changes that will occur when any engineering solution is applied to flooding problems on the lower Chena Hiver. Floods are a common occurrence on the river, and the local plant and animal communities (both aquatic and riparian,) are ad­

justed to and even dependent on them. Modifying water flows in the

Chena will in some measure effect the numbers and habits of many species

in the area, as described in the impact statement before us. The most

important complex of changes will be in water quality in and below the

three impoundments, mostly the two downstream ones. Since the kinds of

changes and their importance to aquatic life are not accurately pre­

dictable at this time, we urge that the design for construction and

operation be kept as flexible as possible. It will be years after

construction before the effects of the project on downstream water

temperature, dissolved oxygen, pH, and other water quality character­

istics will be known. In this connection, we also believe it is extremely important that we learn as much as we can from experiences during project construction and operation. Just as the proposal to build the trans-Alaska pipeline has stimulated research on arctic tundra soils, vegetation, hydrology, and frost processes, the Chena River project should be the incentive and means to conduct similar studies in northern forest, bog, and river sys­ tems. This will require earmarked research funds at every step; the

Alaska Conservation Society urges that a coordinated ecologic research effort be planned and funded along with engineering aspects. We will support requests to Congress and the Alaska Legislature, as appropriate, for these funds.

There are some minor aspects of the discussion of ecologic impacts in the draft statement with which we disagree. For example, we seriously doubt that the overall effect of the project on waterfowl will be favorable - or even measurable. V/e are not as ready as the Corps is to accept the idea that organic debris generated in impoundments will be easily disposed of. It seems probable that suspended, rooted, and floating debris will create recreational and biologic problems for many years after the dams and levees are built. Alleged fishery benefits, too, seem a bit contrived to us.

We are also concerned that at this time many project features are left for future determination and solution. This is especially true of wildlife mitigation. We want to be assured that fiscal authorizations include enough money to take care of these predicted future (post-con­ struction) costs. We also wonder what estimates for these costs have been included in the "cost-benefit ratio," which is apparently so favorable.(l:3 »72) to the proposed project*

To summarize this brief testimony, the Alaska Conservation Society is in favor of the project substantially as proposed in the impact state­ ment of 9 July 1971. While there are few environmental benefits of any significance likely to stem from the project, and whereas some local ecologic losses seem probable, we think the benefits of flood control outweigh these costs. We think the Corps has suggested a plan that will cause as little disturbance to the normal water flows and ecologic processes as possible. The project provides a fine opportunity to learn about and experiment with our boreal forest and northern aquatic eco­ systems. We sincerely urge resource management agencies and research groups, in cooperation with the Corps, to take fullest advantage of this chance. UNITED STATES DEPARTMENT OF THE INTERIOR BUREAU OF OUTDOOR RECREATION PACIFIC NORTHWEST REGION lOOO SECOND AVENUE D6427 Alaska SEATTLE. WASHINGTON 08104

AUG IB 1971

Colonel A. C. Mathews District Engineer Alaska District, Corps of Engineers P. 0. Box 7002 Anchorage, Alaska 99510

Dear Colonel Mathews:

Reference is made to your July 9, 1971, letter requesting our views on the draft environmental impact statement for the Chena River Lakes Flood Control Project, Fairbanks, Alaska. Our review pertaining to the outdoor recreation resources and aesthetic aspects of the project was made in terms of the requirements of Section 102(2) (c) of the National Environmental Policy Act of 1969 (Public Law 91-190).

In general, we find the draft statement to be a comprehensive assessment of the environmental impact of the project. However, we do have some observations based upon our review of the statement. Some pertain directly to the statement itself, while others may more appropriately relate to planning for the project.

1. Environmental Impact of the Proposed Action. We are pleased to note that the statement mentions the desirability of formulating an "environmentally-oriented" land use plan for the newly protected flood plain area. Unfortunately, there is no assurance that such an effort will be forthcoming. In the absence of such a plan, it is quite likely that increased flood protection will stimulate further encroachment into the flood plain. It would be advantageous to expand on the environmental aspects of the "indirect" impact to strengthen the justification and need for comprehensive flood plain planning and management.

Although we can appreciate that many of the details pertaining to the recreation aspects of the Moose Creek Reservoir remain to be finalized, it would be helpful if the statement could address some of the environ­ mental impacts of the recreation features of the project. For example, the construction and placement of the public access road and reservoir recreation facilities may necessitate special precautions to minimize adverse environmental impacts. Screening of utility lines and land­ scaping of the recreation areas are examples of considerations employed in the design stage in recognition of such impacts. 2

The operational characteristics of the Moose Creek Reservoir may present some environmental problems in achieving the full realization of the recreation potential of the project. These are not noted in the state­ ment. For example, it is quite likely that a portion of the recreation development will have to be constructed below gross pool and, therefore, designed to withstand occasional Inundation during periods of flooding. Inundation of sanitary facilities will present some challenge in the project design to forestall any hazards to public health. This phenom­ enon, no doubt, will increase the operation and maintenance of the project in maintaining the recreation areas. In addition, occasional inundation may present some problems in landscaping the recreation areas, thereby somewhat handicapping achievement of the most desirable project aesthetics.

The statement alludes to the possibility of converting borrow areas into trailer camping areas. While we concede that this may be a possibility, our experience is that the conversion of material sites is usually a less desirable alternative as opposed to properly designed and strategically located camping areas. Recreation development at the project should not be planned as a mitigation for environmental damages Inflicted during construction, particularly when recreation is an authorized project purpose.

2. Alternatives to the Proposed Action. We note that there may be an additional nonstructural alternative Involving a combination of partial evacuation of the flood plain, flood proofing of certain struc­ tures, and flood plain zoning which is not specifically mentioned in this section of the statement. This alternative could conceivably provide outdoor recreation benefits resulting from an urban greenbelt concept in the flood plain involving open space, trails, and appropriate recreation development. If this potential did exist, the alternative would have the added advantage of providing recreation opportunities in close proximity to critical urban needs.

We note that the statement Indicates that the 28-mlle dam would have pool fluctuations which would prove adverse to its desirability as a recreation area. While it is true that the pool fluctuations of the 28-mile reservoir impose some limitations on its recreation potential, there are many large flood control reservoirs characterized by wide fluctuations which are heavily utilized for outdoor recreation. At this stage of project planning, it is uncertain that the Moose Creek Reservoir will generate a level of recreation benefits comparable to the 28-mile reservoir or if indeed there will be a non-Federal sponsor to permit recreation development under the provisions of Public Law 89-72. The recreation potential of the Moose Creek Reservoir has yet to be eval­ uated. Pool fluctuation as a partial cause of rejection of the 28-mile reservoir may be premature. The 28-mile reservoir would have a much larger pool available for recreation use during the summer months (although subject to fluctuation) and, perhaps more iitfpprtantly, It would complement the existing Chena River Recreation Area by diversifying the recreation opportunities available. 3

We appreciate the opportunity to review your draft statement and sincerely hope our comments are of some assistance in finalizing the statement and in further planning for the project.

Sincerely yours,

Kaiirice H. Lundy Regional Director cc: North Pacific Division, Corps of Engineers CHEKA RIVER LAKES

ECONOMIC DATA

The attached Economic Data is the latest available cost information taken from Project Document (No. 89, 90th Congress, 2d Session). 25. ALLOCATION AMD AIWORTIOKMEKT O? COSTS.'

a. A1locati on. Cost allocation studies were made for the reconap.er.ded main Chena River reservoir project to determine the equitable distribution of the costs to be chargeable to flood control and recreation. The allocation of m i n Chena River reservoir plus levee project costs to the various purposes was based on the Separable Cost-Remaining Benefits method. The separable costs for recreation for jointly-used facilities for general recreation and fish and wild­ life enhancement were suballocated in the ratio that the benefits ascribed to each bear to the total recreational benefits. A summary of allocated costs for the main Chena River reservoir and levee is shovm in the follo;7ing table. Costs of Little Chena Dam are allocated to flood control. i

SUMMARY OF COST ALLOCATION STUDIES - MAIN CHEKA RESERVOIR PLUS IBVEES (Interest rate 3 - AmorLization period 100 years)

Main Chena'River Reservoir ____ plus' Levees______

Total first cost 102,500,000 Total first cost, discounted 101,804,000 Total investment, discounted 106,005,000 Average annual charges 3,966,000 Average annual maintenance & operations 375,000

FLOOD CONTROL (1)-

First cost 97,487,000 (95.76) Investment 101,685,000 Annual Charges 3,737,000 (94.23) Maintenance and operation 292,000 (77.87)

KECRFATIOd AMD FISH ARP WILDLIFE EMIANCEMSKT (l)

First cost .5,014,000 First cost, discounted 4,317,000 (4.24) Annual charges 229,000 (5.77) Maintenance and operation 83,000 (22.13)

V # Tanat\a-Cucnn R. m Li'.: tie,China Levee & C'nena R. Dam River Dam Total Item ($1000) ($1000) ($1000)

BASED ON ECONOMIC LIFE OF 50-YEARS

FIRST COSTS $102,500 $10,500 !$113,000 INVESTMENT COST 105,955 10,500 116,455* AVERAGE ANNUAL COSTS Interest and Amortization 4,315 428 4,743 Operation and maintenance 355 30' 385 TOTAL 4,670 458 5,128

AVERAGE ANNUAL BENEFITS Flood Control 9,502 680 10,182 Recreation 201 '201 Fis’n L wildlife enhancement '30 30' TOTAL 9,733 680 10,413

RATIO OF BENEFITS TO COSTS 2.1 1.5 2.0

BASED ON ECONOMIC I.IFE OF 100-YEARS

FIRST COSTS $102,500 •$10,500 $113 000 INVESTMENT COST 106,005* ‘10,500 116,505* AVERAGE ANNUAL COSTS Interest and Amortization 3,591 356 3,947 Operation and maintenance 375 30 405 TOTAL 3,966 386 4,352

AVERAGE ANNUAL BENEFITS Flood Control 10,784 771 11,555 Recreation 250 250 n » Fish & v/ildlife enhancement 34 j 4 TOTAL 11,068 771 11,839

RATIO OF BENEFITS TO COSTS 2.8 2.0 2.7

*With future recreation facilities discounted

95 TABLE 2

ALLOCATION OF COST 1O0-AYT: LVALLAG L L 1’Ai LBA'r'S FLOON i ' ; ,y. (Costs iTi *000) ^

Separable Cost-Rcaaintng Priority Incremental 1 £ S ! 1 ______Benefits___ _of Use Cost____

Allocations to Flood Centro 1 First cost $107,987 $11.1,630 $111,630 96.16% 99.40% 99.40% /Annual cost of operation and maintenance 322 325 325 79.51% 80.25% 80.25% Allocat ions to Recreation and fish and wildlife First cost" 4,317 7>4 774 3.84% 0.60% 0.60% Annual cost of operation and maintenance 83 80 80 20.49% 19.75% _19.75% Total Project First cost 112,304* 112,304 112,304

Annual, cost of operation and maintenance 405 405 405

*With future recreation facilities discounted