|
1970 KETTLE GENERATING STATION was the second hydroelectric generating station to be developed on the Nelson River and the largest in Manitoba at that time. Located about 6.4 km downstream from the community of Gillam and 712 km by air from the City of Winnipeg, Kettle's first turbine generator (unit) went into service four months ahead of schedule. Harnessing a 30-m head, or waterfall, the generating station was designed for 12 units, each with a capacity of 106 MW. Kettle was completed in November 1974 with a total capacity of 1,272 MW.
U.S. TO MANITOBA POWER EXCHANGE was approved by the National Energy Board. The Board granted Manitoba Hydro a permit to establish an interconnecting transmission line with three midwestern utilities in the U.S. The 232-km-long, 230-kV transmission line stretches from Winnipeg to Grand Forks, North Dakota. It was completed and placed in service in July for a power exchange with the Northern States Power Company of Minneapolis, Otter Tail Power Company of Fergus Falls, and Minnkota Power Co-operative Inc. of Grand Forks. The line cost $7.7 million, with Manitoba Hydro's share amounting to about $2 million.
TWO LAURIE RIVER GENERATING STATIONS OFFICIALLY TAKEN OVER on June 1 by Manitoba Hydro from Sherritt Gordon Mines Limited. Located about 64 km south of Lynn Lake in northwestern Manitoba, the two originally went into operation in 1952 and 1958 respectively to supply Sherritt Gordon's mining operations in the area. The generating stations, with a total of three units, produce a combined capacity of 10 MW. Laurie II Generating Station is operated by remote control from Laurie I Generating Station. The operating head is 16.8 m.
In conjunction with the Laurie River take-over, a 213-km-long, 138-kV transmission line was constructed from Thompson to connect the two generating stations and the community of Lynn Lake to the provincial power system.
DEVELOPMENT OF LAKE WINNIPEG REGULATION PROJECT BEGAN, under the terms of an agreement between the province of Manitoba and the Government of Canada, reached in February 1966. Manitoba Hydro was authorized to proceed with a plan of the Nelson River development which included using Lake Winnipeg as a reservoir. The Lake Winnipeg Regulation project entailed excavating channels to increase the natural outflow capacity of the lake, and building a control structure to regulate this outflow. Jenpeg Generating Station and the Control Dam were built at the point where the west channel of the Nelson River flows into Cross Lake. Regulation guaranteed adequate minimum flows for hydro-electric generating stations on the Nelson River, according to the plan.
[ top ]
1971 THE NELSON RIVER HIGH VOLTAGE DIRECT CURRENT LINE was first energized. The HVDC transmission line carrying power from the generating stations built on the Nelson River was constructed by Atomic Energy of Canada Limited under the federal-provincial agreement of 1966.
Known as Bipole 1, the transmission line began carrying power in June 1972. Bipole I now operates at 900 kV (±450 kV nominal). The Bipole II line was built later, in 1978.
DORSEY AND RADISSON CONVERTER STATIONS began operating. The construction of Dorsey Converter Station actually started in 1968, but the facility didn't become operational until 1971 with the completion of Bipole I. Dorsey acts as the southern terminus of the HVDC transmission lines. The power produced as alternating current (AC) at the generating stations on the Nelson River is converted to direct current (DC) at Radisson for transmission to Dorsey. When the DC power reaches Dorsey, it is converted once again to AC for distribution to the provincial power system.
[ top ]
1972 THE SECOND MANITOBA TO ONTARIO INTERCONNECTING TRANSMISSION LINE was placed in service. The 230-kV transmission line, which connected Manitoba Hydro's Whiteshell facility near Seven Sisters with Ontario Hydro's terminal station near Kenora, began transmitting power in October. The line was constructed to meet the terms of an agreement reached in 1971. This replaced the original 1956 agreement between the two utilities. Under the new agreement, Manitoba Hydro would sell Ontario Hydro over $26 million worth of electricity by April 1978. In 1974, a new power exchange agreement would be made for the sale of $47 million worth of surplus electricity.
SECOND MANITOBA TO SASKATCHEWAN INTERCONNECTING TRANSMISSION LINE was completed via a 176-km, 230-kV transmission line between Dauphin, Manitoba, and Yorkton, Saskatchewan. An intermediate station was located at Roblin, Manitoba. The interconnection, permitting a power exchange of up to 150 MW, was built in accordance with an agreement made between the two utilities in 1970.
REGIONALIZATION — A NEW ORGANIZATION PLAN adopted by Manitoba Hydro — was designed essentially to decentralize certain Head Office functions, bringing about a more effective customer service. The plan became fully operational by April 1973.
Prior to regionalization, the province was divided into 12 service areas (reduced in 1972 to 11) with offices that provided administration for the local District Offices. The Area Managers reported directly to the Field Operations Division at Head Office in Winnipeg.
Under regionalization, the province was initially divided into three geographic regions: Eastern, Western and Central. The Area Managers in each region reported directly to their respective Regional Directors. Each region was responsible for planning, designing, constructing, operating and maintaining the electrical distribution system within its respective area, and for ensuring reliable and efficient customer service.
Overall system planning and design, power generation, and major construction projects remained the responsibility of staff at Head Office.
[ top ]
1973 THE RATE EQUALIZATION PLAN — DEVELOPED by Manitoba Hydro and Winnipeg Hydro to equalize rates for customers residing in Unicity Winnipeg — was approved by the Winnipeg City Council on June 21 and became effective on August 1. The equalization of rates was required by an Act of Legislature (City of Winnipeg Act) of July 30, 1971, which among other things required that the rates for electricity of both utilities be the same for customers living within the boundaries of the area known as Unicity.
LAST INDEPENDENT ELECTRICAL SYSTEMS IN THE PROVINCE joined Manitoba Hydro when the utility assumed responsibility for the northern communities of Flin Flon and Snow Lake by agreement with Hudson Bay Mining & Smelting Company Limited (HBM & S). Manitoba Hydro acquired the distribution facilities of the Northern Manitoba Power Company Limited, a subsidiary of HBM & S. The Churchill River Power Company Limited, another subsidiary of HBM & S, continued to supply the company's mines, mill, and smelter from its Island Falls Generating Station in Saskatchewan.
With the takeover of Flin Flon and Snow Lake, Manitoba Hydro assumed full responsibility for the transmission and distribution of power for all of the province, with the exception of Winnipeg Hydro's service area.
PLANNING STUDIES FOR LONG SPRUCE GENERATING STATION were completed, and the Long Spruce site, 22.4 km by road downstream from Kettle Generating Station, became accessible by an all-weather road connected to Gillam.
A NEW CORPORATE LOGO for Manitoba Hydro was designed and adopted by the utility.
MORE NORTHERN COMMUNITIES CONNECTED TO PROVINCIAL POWER SYSTEM. The communities of South Indian Lake, Norway House and Cross Lake, served initially by diesel generation, were transferred to the provincial power system. The communities of Gods River and Shamattawa were added to the 21 isolated communities that received electrical service from local diesel generating stations.
[ top ]
1974 MANITOBA HYDRO BEGAN NUCLEAR STUDIES. A small nuclear development department was established to begin the task of potential site identification.
[ top ]
1975 GRANVILLE LAKE AND PAUINGASSI SERVED BY DIESEL GENERATION while Pine Dock and Matheson Island were switched from diesel generation to the provincial power system. The capacity of diesel generation was increased at the communities of Little Grand Rapids, Red Sucker Lake, St. Theresa, and Wasagamack.
[ top ]
1976 MAJOR CONCRETE WORK AT LONG SPRUCE Generating Station was completed, and construction of the powerhouse was well advanced. The earthfill section of the main dam was also underway.
TWO OF THE THREE LAKE WINNIPEG DIVERSION CHANNELS were used for the first time. The Jenpeg Control Dam was completed late in 1975, and the completion of the remaining 2-mile channel between Lake Winnipeg and Playgreen Lake was scheduled for the fall of 1976. Installation of the first bulb-type turbine generators to be used in North America was underway at Jenpeg Generating Station, with the first going into service in 1977.
CHURCHILL RIVER DIVERSION PROJECT BEGAN OPERATING in September when an initial water flow of approximately 283.16 cubic metres per second was released through the Notigi Control Dam. The Control Dam at Missi Falls on the Churchill River channel from Southern Indian Lake was completed. Also work at Nelson House and Thompson during the year.
LAKE WINNIPEG REGULATION works began operating when the Jenpeg Control Dam was completed.
AGREEMENT REACHED ON 230-kV INTERCONNECTION LINE with Minnesota Power and Light Company of Duluth, U.S., to interconnect at the international border in southeastern Manitoba. Manitoba Hydro received approval to build a transmission line from Ridgeway Station to the U.S. border south of Sprague, Manitoba. Licences were also granted for the export of interruptible power and firm power during the period from November 1976 to October 1982.
South of the border, 320 km of line from Hibbing to Duluth were built by two U.S. utilities — Minnesota Power and Light Company of Duluth, and Minnkota Power Cooperative Inc. of Grand Forks.
WORK ON SECOND NORTHERN MICROWAVE SYSTEM BEGAN in conjunction with the Manitoba Telephone System. The microwave system ensured a high degree of reliability for the expanded DC system, and also provided an improved telephone service and live television service to a number of northern communities.
This link was constructed on the east side of Lake Winnipeg and supplied an alternative route for HVDC control and communications. The first buildings and towers were shipped to remote sites during February 1976, and the system was put into service in October 1977.
CRANBERRY PORTAGE EXTENSION ENERGIZED in September, bringing electricity via the provincial power system to the community of 924 residents. The extension was a 230-kV transmission line from Flin Flon to Cranberry Portage. The community of Baker's Narrows, midway along the 48-km extension from Flin Flon to Cranberry Portage, also obtained service. The retirement of the diesel generating station meant an estimated annual saving of over two million litres of diesel fuel.
[ top ]
1977 SOUTH CENTRAL MANITOBA EXPERIENCED SEVERE ICING CONDITIONS, causing the worst impact on Manitoba Hydro's electrical service in the utility's history. Most sub-transmission lines in the area were out of service at various times, and all required some form of ice removal. A total of 7,400 km of power lines were rolled to remove ice during and following the storm, and 1,600 km of power lines were de-iced. Due to these conditions, about 1,500 poles and 600 crossarms were broken and the associated hardware damaged.
The most severely affected small towns and villages were without electricity for periods of up to 49 hours. Hundreds of farm customers were also without — some for as long as six days. The cost to restore service was $1.4 million.
FIRST UNIT AT LONG SPRUCE Generating Station went into service in October. All 10 of the 98-MW units were in service by August 1979. The generating station was officially opened by the premier of Manitoba on June 16, 1979.
THE NORTHERN FLOOD AGREEMENT (NFA) WAS SIGNED in December by the Governments of Manitoba and Canada, Manitoba Hydro, and five Indian Bands — Nelson House, Norway House, Cross Lake, Split Lake, and York Factory. The purpose of the agreement was to establish a mechanism for compensating those individuals or communities adversely affected by the Lake Winnipeg Regulation and Churchill River Diversion Project.
The NFA ensured discussions about the cause or extent of adverse effects, and facilitated the implementation of appropriate response measures. The NFA allows parties to seek resolution through an arbitrator when required.
[ top ]
1978 HIGH PRESSURE SODIUM LIGHTING (HPS) was installed for the first time by Manitoba Hydro. The lighting was installed at the Perimeter Highway and Roblin Boulevard interchanges on the west side of Winnipeg. HPS lighting is more efficient than mercury vapour lighting, which had been used in Manitoba for street lighting almost exclusively for many years.
LIMESTONE DEFERRED due to lower than expected demands for electricity in the province. The scheduled in-service date of Limestone Generating Station was postponed from 1984 until 1987. This resulted in the suspension of further work on the project following the completion of the Stage 1 cofferdam. The Limestone camp, town, and associated works were shut down.
HENDAY CONVERTER STATION, located near Limestone, was completed, thus allowing Manitoba Hydro's second HVDC bipolar transmission line, Bipole II, to be placed in service. Henday began performing the same function as Radisson Converter Station, converting AC power to DC for transmission south to Dorsey Converter Station. Bipole II transmitted power from Henday to Dorsey for the first time on October 1. With the addition of Henday, more conversion equipment was installed at Dorsey.
[ top ]
1979 REHABILITATION WORK AT GREAT FALLS GENERATING STATION began. The work at the 56-year old plant on the Winnipeg River included replacement of the spillway and the west non-overflow dam. Cracks in the water passages underneath the powerhouse were sealed and the head gates reinforced. Repairs to the generating station's electrical and mechanical equipment were also undertaken.
NORTH DAM RECONSTRUCTION AT SEVEN SISTERS GENERATING STATION included the construction of an access road to the work site, foundation preparation, installation of anchors, and placement of approximately 60 per cent of the concrete for the new north dam.
JENPEG GENERATING STATION COMPLETED on the Nelson River. The last of its six turbine generators (units) was placed in service in November. Jenpeg's total winter capacity became 126 MW.
THIRD INTERCONNECTING TRANSMISSION LINE FROM MANITOBA TO SASKATCHEWAN was placed in service in November. The 230-kV transmission line — which extended from The Pas to Saskatchewan Power Corporation's Squaw Rapids Generating Station, later renamed the E. B. Campbell Generating Station — improved the stability of the provincial power system and increased power exchange capabilities for both provinces.
ENERGY RATE STABILIZATION ACT came into force on April 1. It enabled the Government of Manitoba to implement a five-year fixed electricity rate for all customers in Manitoba — other than bulk purchasers and those with separate contracts. The Act provided for the Province of Manitoba to relieve the utility of the costs associated with the foreign debt of Manitoba Hydro. It did so by replacing them with Canadian-equivalent costs based on Canadian rates for similar terms at the date the debt was incurred.
[ top ]
The seventies: a time of development of the Nelson River's hydroelectric resources
From the early 1900s, Manitoba's power planners were aware of the hydroelectric potential of the province's northern rivers. The major stumbling block to such development was how to transmit the power from the north to the more populated areas of the south. By the early sixties, technological advances in the field of power transmission were such that northern power projects could be considered in earnest.
In 1963, the Government of Canada and the Government of Manitoba had entered into an agreement to investigate hydroelectric development on the Nelson River, and to equally share the cost of the research. After exhaustive investigations, a new agreement was signed between the two governments in 1966. Under its terms, the two governments would cooperate and proceed with Phase One Development of the Nelson River. The costs of phase one were estimated to be approximately $300 million. The federal government agreed to provide a long-term loan of $112 million to cover the costs of erecting transmission lines, and installing intermediary and terminal controls and structures. In the agreement, Atomic Energy of Canada Limited (AECL) was designated as the federal government agency and Manitoba Hydro as the province's representative.
The primary objectives of phase one was to convert the rich natural resource of the Nelson River into a power base for industrial and economic development in Manitoba, and to create a potential for the sale of power outside of Manitoba.
Phase One Development of the Nelson River included four main components: construction of Kettle Generating Station; a high voltage direct current (HVDC) transmission system from Kettle to Winnipeg; the Churchill River Diversion Project; and Lake Winnipeg Regulation.
Construction of Kettle began in 1966 and was completed in November 1974. The 1,272-MW generating station consolidated a series of rapids into a 30-m operating head (the waterfall created by Kettle's structure). At that time, Kettle was the largest generating station in Manitoba. One of the keystones to northern hydroelectric development was the transmission system. Manitoba Hydro undertook extensive studies into possible transmission systems as part of the investigations conducted under the 1963 agreement. Alternating current (AC) and direct current (DC) transmission systems were evaluated, and two routes for the transmission lines were assessed — one on the east side and one on the west side of Lake Winnipeg.
In 1966, AECL and private consultants initiated detailed studies with a view to determining which mode of transmission facilities to build and which route to build along. These studies were known as the “Stage One Studies” and included the detailed examination of the eastern and western routes using aerial photographic surveys, soils interpretation, soils sampling, ground reconnaissance, and terrain typing. Also, Manitoba Hydro's load growth forecasts were examined. AECL and Manitoba Hydro conducted extensive system stability studies for both AC and DC transmission systems for three alternative load situations — Manitoba's needs alone, Manitoba's needs plus some export to Saskatchewan, and Manitoba's needs plus exports to Saskatchewan, Ontario, and the U.S. A fourth study made economic comparisons of all the systems.
After careful consideration, direct current (DC) transmission was selected over alternating current (AC) because power losses over long distances would be less and the cost of a DC transmission system amounted to about two-thirds the cost of an AC transmission system. As for route selection, the route on the west side of Lake Winnipeg was chosen because it had better access by road and rail in both southern and northern Manitoba. Also, in spite of being 160 km longer, the route on the west side would be less costly to construct since swamp, muskeg and permafrost conditions were fewer.
This project entailed the construction of two HVDC transmission lines — one line starting at Radisson Converter Station, three kilometres south of Kettle Generating Station; the other starting at Henday Converter Station, 42 km northeast of Kettle. Dorsey Converter Station is the southern terminus for both lines. The transmission systems are referred to as Bipole I and Bipole II. The converter stations are needed to convert the AC power produced at the northern generating stations into DC power for transmitting nearly 900 km to the south. It is then converted back to AC power for distribution to customers. Bipole I was in full operation by June 1972 and Bipole II was completed by October 1978. The portion of the Churchill River in Manitoba, which is downstream of Southern Indian Lake, has a hydroelectric potential of more than 3,000 MW. However, instead of developing generating stations on the Churchill River itself, it was believed that diverting the Churchill River into the Nelson River would be more economical. It was felt that while the Lake Winnipeg Regulation would assure a more dependable water flow in the Nelson River, the Churchill River Diversion Project would increase the power producing potential of the Nelson by as much as 40 per cent.
Three major components accomplished the diversion. One, a Control Structure at Missi Falls, the natural outlet of Southern Indian Lake which controls the outflow and raises the lake level by three metres. Two, an excavated channel from Southern Indian Lake to Isset Lake to allow Churchill River water to flow into the Rat-Burntwood-Nelson river system. Three, a Control Dam at Notigi on the Rat River to regulate the amount of water being diverted.
Under terms of the licence granted in 1972, Manitoba Hydro is permitted to divert up to 850 cubic metres per second (m3/s) of water from the Churchill into the Nelson. The outflow from the Missi Falls Control Dam must be at least 14 m3/s during open water season and 43 m3/s during the ice cover period. The project went into operation in 1977. The regulation of Lake Winnipeg was deemed necessary because in its natural state, the water outflow into the Nelson River is more during the spring and early summer months and less in the fall and winter months. The problem for hydroelectric generation in Manitoba is that the greater volume of outflow is needed in the fall and winter than it is in the spring and summer. With regulation, the outflow from the lake would be reduced in the spring and early summer, and increased during the fall and winter to meet the province's demand for electricity.
Work on the Lake Winnipeg Regulation project began in 1970 and consisted of three main elements. One, the 2-mile Channel, the 8-mile Channel, and the Ominawin Channel, which were built to increase water outflow from the lake in winter. Two, Jenpeg Generating Station and its Control Dam, which was built at the point where the west channel of the Nelson River discharges into Cross Lake. And three, a dam was built at the outlet of Kiskitto Lake to prevent water from backing up into the lake (Kiskitto Lake was later regulated as a wildlife sanctuary area).
Manitoba Hydro was licensed to regulate Lake Winnipeg between the upper storage limit of 715 feet above sea level and the lower storage limit of 711 feet above sea level for power production purposes. The parameters of regulation are expressed in “wind eliminated” terms because the lake's natural characteristics alter water levels at varying points around the lake.
Without HVDC technology and the Lake Winnipeg Regulation, development of the hydroelectric potential of the Nelson River could not have proceeded.
[ top ] |