Wm. Joe Simonds
Table of Contents
The Eklutna Project
By 1950, the boom in American growth and expansion had reached the far northern territory of Alaska. People were pouring into the once desolate and isolated regions. Population increases of more than 500 percent in as little has eight years had stretched the ability of regional providers to supply needed services to the many thousands of new residents. Hundreds of new homes were without electrical service, and business developers, concerned about the critical lack of power, canceled plans for expansion. The future of Anchorage and the surrounding region was in question, and the Bureau of Reclamation held the answer.
The Eklutna Project is located in south-central Alaska about 30 miles northeast of Anchorage midway between Anchorage and the Matanuska Valley, Alaska's most fertile agricultural region. Eklutna Lake lies in a glacial valley in the Chugach Mountains. The Indian village of Eklutna for which the lake and project are named lies 26 miles northeast of Anchorage on the Knik Arm, an inland extension of the Cook Inlet. Eklutna Lake is fed by the waters of Eklutna Creek which begins its journey to Knik Arm some 27 miles upstream from the lake. The climate of the region is considered typical for Alaska although the Anchorage area is usually warmer than the interior regions. Average temperatures range from 11 degrees in January to 57 degrees in July. Precipitation averages between 14 and 16 inches, with the majority falling during the late summer.(1)
The native populations in the region of the Cook Inlet in southwestern Alaska have never lived in complete isolation. Extensive trade networks with the exchange of goods and ideas existed throughout Alaska long before the first non-natives discovered the region in the mid-1700s. The primary inhabitants of the Cook Inlet region are the Tanaina, a branch of Athapaskan Indians that are found throughout Alaska and western Canada. The Tanaina share many cultural similarities with other nearby Athapaskan groups such as the Eyak and Tlingit. In addition to trade, warfare between the Tanaina and other native groups, usually Eskimos, was common with slaves being taken by both sides.(2)
Alaska was discovered by the Russians in 1741. Initially, the Russians confined their activities to the Aleutian Islands, establishing trade networks there. In 1784, the Shelikhov-Golikov Company established a fortified outpost on Kodiak Island near Three Saints Bay. Two years later, the rival Lebedev-Lastochkin Company established a post on the Kenai Peninsula. In 1891, they constructed a second post near the mouth of the Kenai River. For several years, the two rival companies engaged in amicable competition that later developed into hostility and raiding. In 1799, the Shelikhov-Golikov Company was reorganized as the Russian-American Company and, under imperial charter, was granted exclusive right to trade in and occupation of all Russian possessions in North America. By 1800, the Lebedev-Lastochkin Company, burdened by financial difficulties, had abandoned its last foothold in North America to the Russian-American Company.(3)
With the establishment of Russian trading posts in the Cook Inlet region, the Tanaina quickly established themselves as middlemen, coordinating trade between the Russians and other nearby native groups. Since furs had long been a primary item of trade among coastal and interior groups, developing trade between the Russians and the various native groups was relatively easy. By 1796, a trading base had been established near Lake Lliamna on the Alaskan mainland, from which Russian trade expanded into the interior regions.(4)
The early 19th century saw the rapid spread of the Russians out from the Cook Inlet Region. In 1804, the Russian-American Company founded Novo-Arkhangel'sk on Sitka Island, and in 1808, it became the Company's headquarters and the center of the Russian possessions in North America. Other posts were established in the west (Saint Michael, 1833 and Russian Mission, 1836) and northwest (Nulato, 1839).(5)
The growth of the fur industry significantly altered the native way of life. With the increase in fur trapping, less time was spent on other economic activities, leading to an increased dependance on trade for food and other items. The use of skin clothing was quickly replaced by clothing made of fabric, and firearms replaced the bow and lance. As a result of increased reliance upon trade for food and other material needs, the native groups became more and more associated with the trading post, often settling nearby.(6)
Along with guns and European goods, the fur trade brought other things to the native Alaskans. Epidemic diseases plagued the native peoples, the most disastrous being smallpox. In 1836-1840, over 4,000 natives died from the effects of the disease. In addition, other contagious diseases such as syphilis and tuberculosis took a heavy toll.(7)
Although members of the Russian Orthodox clergy had been present in Alaska since the 1790s, extensive missionization did not begin until the 1840s. Hieromonk Nikolai became the first priest at Saint Nicholas in 1845, serving the Cook Inlet, Prince William Sound, and the interior regions. The vastness of the Alaskan wilderness and the small number of priests made missionization difficult. While many natives accepted Christianity without much resistance, it seems likely that they had little understanding of the Orthodox beliefs and accepted it as one of the costs of the fur trade.(8)
In 1867, the United States agreed to the Alaska Purchase, ending Russian control of the region. Following purchase of Alaska, the number of whites entering the region increased gradually. The fur trade was taken over by the Alaska Commercial Company which built upon and expanded the trade networks established by the Russian-American Company. Major gold discoveries in the 1880s and 1890s accelerated the influx of whites into Alaska, and by the turn of the century, American control and exploration of the interior regions was complete.(9)
With the decline of the gold rush in the early 1900s, all but the most die-hard miners left Alaska. Those who remained began to establish an extensive network of trails linking the interior regions with the coast. Following the establishment of Fairbanks in 1902, river steamers began regular runs up the Yukon and Tanana Rivers. In 1906, construction of the Alaska Railroad began in Seward. The Federal Government took over in 1914 and Anchorage became headquarters for the project. Following completion of the railroad in 1923, offices and maintenance facilities permanently located in Anchorage, and many who worked on constructing the railroad stayed to settle the region.(10)
In 1935, 200 families from the drought-stricken Midwest were relocated in Alaska's Matanuska Valley by the Alaska Rural Rehabilitation Corporation. In 1941, the outbreak of World War II created a small population boom in Alaska when the Defense Department hurriedly moved to arm and defend the territory. Thousands of workers moved in to help construct Fort Richardson and Elmendorf Field near Anchorage. In 1939, the population of Anchorage was just over 3,000 people. By 1948, the population had risen to an estimated 19,000 people, an increase of more than 500 percent.(11)
Beginning in the early 1940s, electricity began to become a scarce resource. Black-outs were frequent, prices high, and many homes had no power at all. When Anchorage was primarily the construction headquarters for the Alaska Railroad, power was supplied by a 900-kilowatt (k/w) steam powered generating unit. Following incorporation, the city became responsible for distribution of electricity. In 1927, the city entered into a contract with the Anchorage Light and Power Company (ALPC) which constructed the Old Eklutna Hydroplant. Its first 1,000 k/w began service in 1929, followed by a second unit in 1935. In 1937, ALPC installed a 700 k/w diesel power generating unit to supplement existing units.(12)
The increased population brought about by the large scale military expansion at the start of World War II placed great demands on the existing power system. By 1945, demand exceeded supply, and ALPC began looking for new sources of power. In 1946 ALPC installed an additional 600 k/w diesel powered unit, and attempted to operate the old railroad steam plant during periods of high demand, but the old plant proved undependable. In 1947, the ALPC leased and then purchased the stern-half of a wrecked ocean-going tanker, the Sackett's Harbor, and began using it's boilers and generating equipment as a powerplant. This system proved to be reliable, producing 3,000 k/w, but was clearly a stop-gap measure. By 1948, the situation had once again become critical and voters approved a bond measure to purchase and install another 1,000 k/w diesel powered unit. The area's power problems were only solved with the approval of the Eklutna Project in 1950.(13)
On October 1, 1948, the Commissioner of Reclamation received the first report on the potential power development in Alaska via the Eklutna Project. The report, submitted by Joseph Morgan, Chief of the Alaska Investigations Office, concluded that:
The use of electric power in the power market area is expanding so rapidly that new installations of hydroelectric power plants are needed as quickly as possible to meet the emergency requirements of existing loads and to permit the establishment of new industries to support increases in population and economic development.(14)
The report also determined that the project was feasible from both an engineering and economic standpoint and recommended that construction be authorized.(15)
The project was authorized on July 31, 1950, by Public Law 628, 81st Congress, 2nd Session, H.R. 940, to " . . . encourage and promote the economic development of the territory of Alaska . . .." (16)
Several plans for development were investigated and rejected for a variety of reasons before a final plan was adopted. One plan called for a series of dams on Eklutna Creek, but this was rejected due to the poor quality of materials available for construction. A second plan called for rehabilitation and enlargement of the existing Eklutna Powerplant with water supplied by a conduit from the lake, but this plan was rejected due to a poor benefit/cost ratio. Both these plans were based on the desire to continue use of the existing plant. Further investigations determined that any attempt to continue full-time operation at the existing plant would severely reduce the potential output of the new powerplant and it was decided that the old powerplant should be abandoned.(17)
The 1948 report that was the basis for authorization of the project called for construction of a new dam to raise the level of the lake to an elevation of 875 feet above sea level with the tunnel intake at 830 feet. The report also proposed that a three unit powerplant be constructed and supplied with water via an exposed steel penstock running down the hillside from the end of the tunnel. The final plan placed the penstock in a tunnel and reduced the generator installation to two units.(18)
When the first bids for construction of the tunnel and dam were opened in July 1951, the two bids submitted were both rejected because they were each almost twice Reclamation's estimates. The specifications were modified and readvertised. The new specifications provided for alternate schedules. Schedule No. 1 called for the construction of a low-level tunnel and modification of the existing dam. Schedule No. 2 called for construction of the high-level tunnel and construction of a new dam under a later contract. Four bids were received in the Denver office by the closing date of September 11, 1951. When the bids were opened, it was determined that schedule No. 2 was economically less advantageous than Schedule No. 1. A low bid for schedule No. 1 of $17,348,865 was submitted by Palmer Constructors, a joint venture of Peter Kiewit Sons' Company, Morrison-Knudsen Company, Inc., and Coker Construction Company. The contract was awarded to Palmer Constructors on September 15, and notice to proceed was transmitted to the contractor on October 15, 1951. The contract called for the completion of the project by December 22, 1954.(19)
Palmer Constructors let four subcontracts for work performed under the primary contract. Construction of the intake and trashrack sections was let to Ben C. Gerwick. Excavations and backfill for the intake structure was let to Gerwick and the Hydraulic Dredging Company. Subcontracts for processing and stockpiling aggregates were let to the Alaska Aggregate Corporation and the Northern Ready Mix Company.(20)
To house their employees, Palmer Constructors built two construction camps, one near the site of the powerplant and the other at Eklutna Lake. The camps had spaces and utilities for trailers, dormitory accommodations, and a mess hall. During the first year of construction, Government personnel were required to provide their own housing. This was extremely difficult due to the short supply of housing and high rent charges. As a result, it was difficult to recruit and hold qualified personnel. This situation was relieved when the Government contracted for the construction of 49 permanent and temporary houses in late 1952.(21)
During the four year construction period, Palmer Constructors employed an average of 155 workers with a maximum of 343 during 1953. Wages for the workers ranged from a low of $2.735 per hour for laborers to a high of $3.57 per hour for crane operators. Divers were paid $40.00 per 6 hour shift and $20.00 per hour for any time over 6 hours. In addition, they received an additional $1.00 per foot for depths between 60 to 100 feet and $2.00 per foot for depths over 100 feet.(22)
The first work to be performed under the primary contract was open cut excavations at the tunnel gate shaft and at the downstream tunnel adit in October 1951. The contractor wanted to get underground before the severe winter weather set in. Excavations on the 200 foot deep gate shaft proceeded without significant difficulty, and were nearing completion when the first freeze came. Work at the downstream portal did not go as well. Difficulty constructing the service road leading to the site delayed the start of excavations considerably, and it was well into the most severe part of winter before the portal was holed in.(23)
Following completion of the gate shaft, a heading was advanced over 700 feet upstream beneath the lake bed. This section was then lined with concrete and steel bulkheads installed at the end. The remaining sections of the upstream portion of the tunnel would be excavated by dredging from the lake. The first mile of excavations from the downstream portal were very difficult with the rock being extremely faulted with many water filled channels. On November 9, 1952, a major cave-in at the downstream heading flooded the tunnel, halting work on the heading for two months while a dewatering system was installed. At the time of the cave-in, the water flow in the tunnel was estimated to be 10,000 gallons per minute.(24)
While work on the dewatering system was taking place in the downstream portion of the tunnel, excavations from the upstream heading continued. Excavations were carried out by blasting with each blast consisting of 24 to 40 holes drilled to an average depth of 9 feet. Each set of holes was loaded with between 160 and 170 pounds of explosives with the heading advancing approximately 8 feet with each blast. Materials loosened during the blast were removed from the tunnel in 4-cubic-yard (cu/yd) dump cars pulled by electric-powered locomotives. Similar equipment was used in both headings.(25)
Because of the nature of the rock encountered, steel supports were required for about 70 percent of the tunnel. The supports usually consisted of 5-inch H-beams placed on 4-foot centers. This varied according to the quality of rock encountered in a given section. Over 1,682,000 pounds of 4-, 5-, and 6-inch steel H-beam supports were used.(26)
The two headings were holed through on October 15, 1953. After holing through about two months was spent cleaning the invert (floor) section and preparing the tunnel for lining. Concrete lining operations began in January 1954, on a one shift per day basis. This was later increased to three shifts a day. Delays were common, mostly due to problems with the aggregate trains. Water also delayed placement. Prior to concrete placement, the permanent drainage system was installed in the wet sections of the tunnel. The original specifications called for steel reinforcement in the entire length of the tunnel. Because of the good quality of rock in many sections, much of the reinforcement was eliminated, saving about $800,000. Tunnel lining operations were completed on December 18, 1954. Lining of the gate shaft began in late June 1954, and was completed in early September.(27)
Dredging operations for the intake structure began in May 1952 and were completed late the following November. Dredging involved the removal of 410,000 cu/yd of material from the trashrack and intake areas, 70 feet below the surface of the lake. The intake consists of 225-feet of precast concrete conduit manufactured in 16-foot sections. The sections were lowered into place by a floating crane and assembled by divers. The first two sections were in place and backfill complete by early December 1952, when operations were halted for the winter. The remaining sections and the trashrack were placed the following summer. The final work occurred in November 1954, when divers returned to remove the bulkhead, allowing water into the tunnel.(28)
Rehabilitation of the Eklutna Dam was carried out in conjunction with construction of the intake structure. Private interests built the dam in the early 1940s. It had and has an uncontrolled overflow spillway and 19 hand operated headgates. Rehabilitation involved construction of a small dike on the southeast end of the dam, raising both abutments, rebuilding a small bridge across the dam, and placement of riprap for slope protection. Due to the poor condition of the headgates, they are left in the closed position at all times. Eklutna Lake has a capacity of 182,100 acre-feet (ac/ft) with a surface area of 3,247 acres.(29)
Excavation for the surge tank, located at the downstream end of the tunnel, began in February 1953. A small pilot shaft was drilled upward through the center of the tank and used as a muck chute. The remainder of the tank was excavated in 5-foot lifts from the top down. The excavated material was dropped down to the main tunnel and removed by mine cars. Excavations1 were completed in August 1953. The entire surge tank is reinforced with 6-inch H-beams placed on 4-foot centers for the entire height of the tank. The concrete lining was place during the fall of 1954.(30)
Work on the penstock tunnel began in late November 1952 with open-cut excavations at the downstream end. Because the ground water table was higher than the lowest point in the open-cut, continuous pumping was required to keep the excavations free of water. The entire length of the inclined tunnel was driven upward from the downstream end. Steel liner plates were used for the first thirty feet of the tunnel with conventional H-beam supports used in the remainder. Men and material were transported to the heading via a mine car that was mounted on a deck supported by steel H-beams. The deck ran through the center of the tunnel with the area below the deck used as a muck chute. The 53 slope of the tunnel was sufficient to allow rock and debris to flow down the incline to the bottom where it was removed by mine cart. The penstock tunnel was "holed through" into the upper tunnel on February 5, 1953.(31)
Following completion of excavations, the penstock tunnel was cleaned and prepared for placement of the steel penstock, reinforcement steel, and concrete lining. That portion of the penstock from the down stream portal through the lower bends was moved into place and embedded in concrete from the downstream portal. The inclined portions and the upper bends of the penstock were lowered into place and embedded in concrete from the upper end of the inclined tunnel. The sections downstream from the portal were embedded in a concrete anchor block supported on steel piles driven into bedrock. The last sections of penstock were embedded in concrete in early July 1954, completing work under the primary contract for the tunnel and penstock.(32)
Eklutna Tunnel is a 4.5 mile long, concrete lined, pressure tunnel 9-feet in diameter with a capacity of 640 cubic feet per second (cfs). The intake structure consists of a precast concrete trashrack just over 133-feet long, and 225-feet of precast conduit 9-feet in diameter. The trashrack is 60-feet below the surface of the lake at the end of a 500-foot long, 100-foot wide inlet channel. The dam, as modified, is an earth- and rock-filled structure, 555-feet long and contains approximately 5,000 cubic yards of material. The penstock is a welded steel pipe, 1,088-feet long, encased in concrete. It varies in diameter from 91-inches down to 75-inches.(33)
Bids for construction of the Eklutna Powerplant were opened on May 27, 1952. Of the three bids received, the lowest was submitted by the Rue Contracting Company of Fargo, North Dakota. They bid $2,579,607, almost $500,000 less than the engineer's estimate. The contract was awarded on June 2, 1952, with work beginning on July 2, 81 days before receipt of notice to proceed. The contractor was given 830 days to complete all work under the contract.(34)
Several other contracts were let in association with construction of the powerplant. The contract for two, 16,000 kilo-volt (k/v) generating units was let to the Pacific Oerlikon Company of Tacoma, Washington, at a cost of $474,294. Two, 25,000 horsepower (hp), vertical shaft turbines to drive the generators were supplied by Newport News Ship Building Dry Dock Company of Newport News, Virginia. The contract price for the turbines was $335,000. Two speed regulating governors for the turbines were supplied by the Woodward Governor Company of Rockford, Illinois, for $58,686, and two, 20,000 k/v transformers were provided by the Westinghouse Electric Corporation of Denver, Colorado, for $114,242.(35)
The work under the powerplant contract began with work on relocation of a portion of the Glenn Highway around the powerhouse site. This work began in early July 1952 and was performed by the Munter Construction Company under subcontract with the primary contractor. This was one of seven subcontracts let by the primary contractor. Traffic was routed over the relocated section the following June, and the final surface was placed in September 1954.(36)
The subcontract with Munter Construction also called for the excavation of the tailrace conduit and channel and the powerhouse foundation. Excavations for the tailrace conduit and channel began in July 1952 and was essentially complete by the end of 1952. Excavations for the powerhouse were conducted during the 1952 and 1953 construction seasons. Throughout the excavation period, high ground water was a problem, requiring continuous pumping to keep the excavations free of water.(37)
Due to the unstable nature of the ground at the powerhouse site, the foundation was placed on heavy steel piles that were driven into bedrock. Pile driving operations were carried out in conjunction with foundation excavations. Pile driving began on June 17, 1953, and was completed by August 22. Piles were driven into bedrock until they reached a point were they could be driven no further, the average penetration into bedrock being about 5-feet. Foundation piles were also used for the machine shop, transformer structure, and penstock anchor block. In all, more than 280 piles totaling over 18,000 linear feet were driven.(38)
Installation of the remaining portions of the penstock and the penstock wye-branch were carried out in May 1954. Some difficulty in obtaining a watertight seal was experienced, but field repairs were able to overcome the problem. The first of two 66-inch butterfly valves arrived at the site on November 26, 1954, with the second valve arriving a few days later. Installation of the valves began immediately and progressed without difficulty. Installation and testing were completed on December 13.(39)
Installation of the generating units began in April 1954 with work to install the embedded portions of the turbines. The embedded portions of turbine unit no. 1 were encased in concrete on June 7, 1954, followed by embedding of unit no. 2 on July 20. Following encasement in concrete, the units were hydrostaticaly tested to 500 pounds per square inch. This was then reduced to 350 pounds per square inch and maintained at that level for seven days while the concrete cooled and cured. Installation of the generators began in late June 1954 with work on unit no. 1. Work to install generator no. 2 began in late October. Work on unit no. 1 was completed on December 31, 1954, and the unit was started for testing. Testing was completed on January 7, and unit no. 1 was placed into service on January 8, 1955. Testing of unit no. 2 began on March 26, 1955, and was completed on April 1, when the unit was placed into service. The project was transferred from the construction phase to operation and maintenance on July 1 ,1955.(40)
Eklutna Powerplant has two, 16,000 k/w generating units each driven by a single, 25,000 hp turbine turning at 600 revolutions per minute (rpm). The combined rated capacity of the powerplant is just over 33,000 k/w. The original power installation included 5 substations and over 66 miles of transmission lines.(41)
The Eklutna Project was dedicated on August 29, 1955. Officials in attendance included the Commissioner of Reclamation, Wilbur A. Dexheimer, the mayors of Anchorage and Palmer, the Commanding General of the Army in Alaska, and numerous other officials. The benefits to the region were immediate. By providing a firm source of power far in excess of needs, the frequent power outages and brownouts that had plagued the region were no longer a concern. In addition to the immediate benefits, the excess energy helped fuel future growth and the development of industry throughout the region.(42)
In April 1963, after eight years of almost continuous operation, unit 2 was shut down for a complete overhaul. Work began on April 22 and was completed on June 19. A similar overhaul for unit No. 1 was scheduled for the following year, but one of the most significant events in the history of Alaska delayed this work.(43)
At 5:36 p.m. on March 27, 1964, the Anchorage region was hit by a severe earthquake measuring between 8.4 and 8.6 on the Richter scale. The tremor lasted several minutes and caused widespread damage and destruction. At the time of the quake, the powerplant was operating at near maximum output. The quake caused the immediate shutdown of the plant, plunging the entire area into darkness. A quick survey of the plant and switchyard by plant personnel revealed significant damage to two circuit breakers in the switch yard located on the roof of the powerhouse but no apparent damage to the two generating units. At 5:55 pm, less than 30 minutes after the quake, the damaged circuit breakers in the switchyard were isolated from the rest of the system and unit No. 2. was restarted, restoring power to the station.
As project personnel began arriving at the plant, reports of damage began to come in. A 7,500-foot section of the Palmer transmission line had been carried away by a snow slide, leaving the Palmer region without power. At the Anchorage Substation, equipment had shifted on its bases, but, after minor repairs, the station was in operational condition. At 10:10 p.m., after repairs to bypass the damaged circuit breakers at the powerplant, the Anchorage line was energized, restoring power to the city. Service to the Matanuska Electric Association at the Reed Substation was restored at 10:43 p.m., with service to the Palmer Substation restored early the following morning.
At 12:12 a.m., March 28, both units at the powerplant went off-line when pressure in the penstock dropped suddenly. At 12:40 am, the pressure returned to normal and unit no. 2 was restarted. Personnel were sent to the lake to assess any damage there and report back. No apparent damage was noted and the headgate was in full open position, although there was very little water flow. At 1:30 am, low pressure again forced the shutdown of the units. It was believed that a landslide beneath the surface of the lake had partially plugged the trashrack. In an attempt to relieve the problem, water was kept running through the penstock in hope that the trashrack would clear. At 3:55 am, the pressure returned to normal and one unit was restarted. At about 8:00 am, the pressure began to drop once again and a significant amount of debris was noted in the tailrace, indicating a break somewhere in the penstock system. At 2:40 pm, debris in the system caused damage to unit no. 1, causing the first of many shutdowns to remove rocks and other debris from the turbine units.(44)
To help prevent serious damage to the turbine units, a screen of 2-inch chain link mesh was placed in each penstock between the butterfly valve and turbine scroll case of each unit. This was effective in preventing many large rocks from reaching the turbines. It was also discovered the if the output was kept below a certain level, that large rocks were not drawn through the penstock. In addition, unit no. 1 was used as the primary unit in order to prevent damage to newly overhauled unit no 2.(45)
On April 19, 1964, an underwater inspection of the intake structure and underwater conduit showed that at least one joint of the concrete conduit was damaged, allowing debris into the penstock. Because of the critical need for power during the days and weeks following the disaster and the significant damage to other power facilities in the region, it was early May before the powerplant could be completely shut down and permanent repairs made.(46)
On May 5, Reclamation officials signed a contract with Peter Kiewit Sons' Company to make further inspections of the intake sections and repair the structure as needed. On May 9, Reclamation shut the powerplant down and prepared for inspection of the tunnel and penstock. Underwater inspection of the intake structure and conduit revealed that 10 of 15 joints in the conduit had separated and that the intake structure and trashrack had moved more than 40-inches towards the center of the lake. Divers also discovered a large amount of debris in and around the headgate requiring more than 12 hours to clear before the gate could be closed and the tunnel dewatered.(47)
With the headgate closed and the tunnel dewatered, an inspection team was able to walk the entire length of the tunnel. Their inspection revealed no damage to the tunnel itself, but debris as deep as 18-inches was deposited throughout the first 3½ miles. While most of the debris was less than an inch in diameter, rocks as large as footballs were found. Between 1,500 and 2,000 cu/yd of material were found in the tunnel.(48)
To inspect the steeply inclined penstock, the penstock was filled with water and two inspectors in a rubber raft "floated" down the 863-foot incline. The rate of decent was controlled by the release of water through the butterfly valves. The inspection revealed no significant damage to the inclined portion of the penstock. Initial inspection of the dam indicated that the dam had suffered no significant damage, but subsequent inspections revealed a high degree of settlement beneath the concrete portions of the dam and spillway. Reclamation to declared the dam unsafe. All of the spillway gates were opened allowing free flow through the gate structure to prevent pressure build-up which could cause the structure to fail completely.(49)
Temporary repairs of the intake structure and conduit were carried out by Peter Kiewit Sons' Company between May 5 and June 25, 1964. The contractor removed gravel and debris from the conduit and intake structure and repaired separated conduit joints. The joints were repaired using expandable steel rings that were placed inside the pipe. Separation occurred at a total of ten joints with the maximum separation being 10-inches. At joints where the separation was less than 4-inches, a single 12-inch wide ring was used. At joints were the separation exceeded 4-inches, two rings were used. Following completion of joint repairs, divers cleared the conduit of as much debris as possible.(50)
Several problems complicated cleanup of the tunnel. Access was the biggest problem. Access to the tunnel could only be achieved through openings of less that 3-feet in diameter. Further complicating the situation was the fact that access from the upstream end was through the 220-foot tall gate shaft. Water leakage further complicated clearing operations. Rock removal operations by force account began on a two shift per day basis using wheelbarrows to remove the muck. This method proved to be costly and slow, and, after one week, it was determined that a mechanical means would have to be employed. Since the Kiewit Company was well experienced in tunnel operations and had the necessary equipment available, a contract was negotiated whereby the Kiewit Company would clear the first 3½ miles of the tunnel.(51)
Mobilization by the Kiewit Company was slow because equipment that did not fit through the narrow openings had to be broken down or cut into pieces and reassembled once inside. Mucking operations were carried out using a 1½ cu/yd haul unit, a slusher, and drag bucket. The drag bucket was drawn through the gravel and muck by a cable and pulley system to the loading chute of the slusher unit, which discharged the material into the haul unit. The haul unit then delivered its load to the gate shaft were it was lifted out by a 3/4 cu/yd lift bucket. The process was slow, at times taking as long as 45 minutes for the haul unit to make a round trip to the gate shaft and back.(52)
Following the final clean up and removal of the mucking equipment, three heavy chainlink screens, each 4-feet high, were placed at 100-foot intervals downstream from the headgate. The gate was partially raised allowing water to flow into and partially fill the tunnel. The gate was then closed and the tunnel drained for inspection. A small amount of material was removed from behind the screens. Following removal of the material, the tunnel was again filled and the powerplant placed into operation for 48 hours. After 48 hours, the powerplant was shut down and the tunnel drained. Inspection of the tunnel revealed approximately 23 cu/yd of material trapped by the screens. This was removed and the plant placed into operation for a second 48-hour period. Following the second 48-hour operating period, the tunnel was once again drained and less than 2 cu/yd of material was held by the screens. It was determined that the tunnel had been sufficiently cleared of material, and on July 2, 1964, the powerplant was returned to normal operation.(53)
Replacement of the intake structure and permanent repairs to the conduit were carried out in the spring of 1965. The contract for the work was awarded to the Mason-Osberg Company, a joint venture of the Mason Construction and Engineering Company and the Osberg Construction Company on February 1, 1965. Their bid was $633,631. Notice to proceed was transmitted on February 12, and work under the contract began on February 26.(54)
Work at the site began with clearing of ice that had accumulated along the shore of the lake. Work on the coffer dam began on March 15, and the construction site was ready to be drained on March 25. Water was drained through the tunnel exposing the intake structure and conduit. The existing intake structure and the first four sections of conduit were abandoned, but left in place. The next four section were removed to make way for the new intake structure. The remaining section were sandblasted and repaired using stainless steel joint repair rings. Repairs to the conduit were completed on April 28.(55)
The contractor placed concrete forms for the new intake structure April 12, and set the trashrack into place the last week of the month. Beginning May 2, water was pumped from the lake into the intake structure area. Removal of the coffer dam began the following day and was completed by May 7. Work under the contract was accepted as complete on May 14, and Unit no. 2 was restarted May 18, 1965. The previously scheduled overhaul of unit No. 1 began while the plant was shut down for repairs to the intake structure. This work was carried out between April 20 and June 3.(56)
Because of the severity of damage to the dam, it was determined that the best course of action was to construct a new dam downstream from the existing dam. Bids for construction of the new dam were opened on March 16, 1965. The low bid of $1,233,470 was submitted by A & B Construction Company of Helena, Montana, which was awarded the contract on March 26. Work on the new dam began in early April when the contractor started stripping the spillway area and right abutment. When excavations in the spillway area were complete, earthwork and excavations were halted to allow concrete placement in the spillway structure. Drilling for the spillway anchor bars began in early June and was completed by the end of the month. The first forms were set in place on June 10, and placement of concrete took began on June 17. The spillway floor was completed by mid-August, with the conduit sections and cut off collars completed by the end of August. The stilling basin and chute walls, and the second stage concrete in the inlet section were placed in mid-September with all concrete work completed by September 30. Because the tunnel acts as the river outlet, no other concrete work was necessary.(57)
Excavations were restarted the end of August with embankment placement operations beginning in early September. Embankment placement continued at a steady pace with only minor delays due to weather in October. The new dam was completed and all work accepted on November 15, 1965, 327 days ahead of the contract completion date.(58)
The new Eklutna Dam is an earth and rockfill structure 815 feet long and 51-feet high containing 85,000 cu/yd of material. The spillway is a rectangular concrete conduit through the dam with an uncontrolled overflow crest. The maximum capacity of the spillway is 3,315 cfs. There are no outlet works in the dam as the power tunnel serves in that capacity. Eklutna Lake has a total capacity of 213,271 af with a maximum surface area of 3,420 acres.(59)
In addition to the damage to the dam and intake structures, the earthquake cause considerable damage to other project features. Dirt and debris that passed through the penstock and turbine clogged the tailrace conduit, depositing over 100 cu/yd of material in the conduit. Cracking and settlement along the 2,000-foot tailrace channel had the effect of squeezing the sides of the channel. The Anchorage, Reed, and Palmer Substations all received significant damage, but were able to quickly resume operation. Snow slides had carried away several thousand feet of transmission lines that had to be replaced. While the powerhouse escaped significant damage, other structures at the station received heavy damage. Both the project office and warehouse were heavily damaged but could be repaired. The automotive repair shop was so severely damaged that it had to be rebuilt at a new location.
Considering the power of the quake, the project held up well, testifying to the skill of its designers and builders.(60)
In October 1965, in commemoration of their outstanding work under very difficult conditions, Secretary of the Interior, Stewart Udall, awarded the Eklutna Project operations team a unit citation for excellence of service in the days and months following the earthquake.(61)
In 1967, the Department of Interior established the Alaska Power Administration (APA) to direct the future course of Federal participation in water resource development in Alaska. Under the order establishing the APA, all responsibility for the operation and maintenance of the Eklutna Project was transferred from the Bureau of Reclamation to the APA. The transfer of operational responsibility took place on June 16, 1967.(62)
In 1995, after 40 years of operation by agencies of the federal government, a contract for the sale of the powerplant and related facilities was negotiated with local utility companies, including the Matanuska and Chugach Electric Associations. The transfer is scheduled to take place in early 1996.(63)
Because there are no agricultural benefits directly associated with the Eklutna Project, no lands were withdrawn for later settlement. But there can be no doubt that the addition of a secure supply of power to the region played a significant role in the growth and development of Anchorage and the surrounding area.
The primary purpose of the Eklutna Project is the generation of power. There are no agricultural uses directly associated with the project. But there are indirect benefits to the agricultural community. The power supplied by the project's generators helps to ensure that those farms and ranches that need to pump their water from wells or remote locations will have their needs met by the simple flick of a switch. In addition, Eklutna Lake provides numerous recreational opportunities for residents and visitors in the area.
Though not a true "reclamation" project, the Eklutna Project was the right project at the right time. Faced with severe shortages, the people of Anchorage and the surrounding regions needed answers quickly. The answers were found in the experience and expertise of Reclamation engineers and planners who, following many decades of providing valuable resources to fuel the growth of the American West, were able to provide the one resource needed by the people of Alaska. The construction of the Eklutna Powerplant ensured the people of the Anchorage region a secure future.
Denver, Colorado. National Archives and Records Administration: Rocky Mountain Region. Records of the Bureau of Reclamation. Record Group 115. Project Histories: Eklutna Project," 1950-1967.
United States Department of Interior, Bureau of Reclamation. Eklutna and the Alaskan Earthquake. Juneau: Alaska District Office, Bureau of Reclamation, December 1964.
________. Eklutna Project, Alaska. Alaska Investigations Office, Juneau, October 1948.
________. Reclamation Project Data.Washington: US Government Printing Office, 1961
________. Rehabilitation of Eklutna Project Features Following Earthquake of March 1964. A supplement to Technical Record of Design and Construction, Eklutna Dam, Tunnel and Powerplant. Denver: Bureau of Reclamation, June 1967.
________. Technical Record of Design and Construction, Eklutna Dam, Tunnel and Powerplant. Denver: Bureau of Reclamation, March 1958.
Morgan, Joseph M. "Eklutna - Number-One Job in Alaska." Reclamation Era. February 1949, 35.
Reclamation Era. "Commissioner Dexheimer Dedicates Eklutna Project". November 1955, 90.
________. "Notes for Contractors". July 1952, 180.
________. "Notes for Contractors". March 1952, 72.
Helm, June, vol. ed. Handbook of North American Indians: Subarctic. Vol. 6. William C. Sturtevant, gen. ed. Washington DC: Smithsonian Institution, 1981.
Plumley, Bob. Plant mechanic, Eklutna Powerplant. Telephone interview by author. 16 October 1995.
About the Author
William Joe Simonds was born and raised in Colorado and has a clear understanding of the importance of water in the American West and its affect on the development of that region. He attended Colorado State University where he received a BA in History in 1992 and a Masters in Public History in 1995. He lives with his wife and two children in Fort Collins, Colorado.
1. US Department of Interior, Bureau of Reclamation, Eklutna Project, Alaska, (Alaska Investigations Office, Juneau, October 1948), 1-3; US Department of Interior, Bureau of Reclamation, Technical Record of Design and Construction, Eklutna Dam, Tunnel and Powerplant, (Denver: Bureau of Reclamation, March 1958), 1.
40. Ibid., 194-196; Denver, Colorado,National Archives and Records Administration: Rocky Mountain Region, Records of the Bureau of Reclamation, Record Group 115, "Project Histories: Eklutna Project," Vol. V, 1955, 4 (hereafter referred to has "Project History" followed by volume number, year and page.).
47. Ibid.; United States Department of Interior, Bureau of Reclamation, Rehabilitation of Eklutna Project Features Following Earthquake of March 1964, A supplement to Technical Record of Design and Construction, Eklutna Dam, Tunnel and Powerplant, (Denver: Bureau of Reclamation, June 1967), 9-10.