Shoal Lake aqueduct — ensured safe, reliable source for city’s water supply

by Lorne Shropshire

In March 1919, the city of Winnipeg witnessed one of the largest engineering tasks ever undertaken in North America with the completion of a subterranean aqueduct, 156 kilometres in length. It allowed the pristine waters of a remote northern Ontario lake to flow through the city’s watermains. 

The development of Winnipeg’s water system was one reflection of the city’s expectations, and potential for growth, that popularized the early years of the century.

In the years preceding 1880, Winnipeg received its water from private wells situated throughout the city and its confines. Water was delivered in casks to homes and businesses by watermen using horse-drawn carts in the summer and sleighs in the winter months.

Despite a bylaw prohibiting the use of river water for human consumption, those without access to wells were known to surreptitiously siphon their supply from the Red River. A spot at the foot of Lombard Street was one popular location. Not only was this an inefficient system incompatible with urban growth, it lacked proper sanitary controls, and thus posed a potential health threat.

At the beginning of 1880, water mains were installed in some areas of the city in preparation for the introduction of a more efficient delivery system.

Rescinding the prohibition on river water, the city let a contract to a private concern called the Winnipeg Waterworks Company, founded by E.H. Bissett. The company was granted an exclusive 20-year contract, effective December 23, 1880, to supply the city with domestic water. Bissett obtained his supply from the Assiniboine River. The pumphouse and intake were located at Armstrong’s Point, on the north bank of the river, east of the Maryland Street bridge and near the lower end of Mulligan Avenue (now Sherbrook Street).

This system, though an improvement, was less than satisfactory. Assiniboine River water had a unpleasant taste and smell throughout the spring, summer and fall months. Also, availability was haphazard as the company could only supply part of the city, and the supply was inadequate for firefighting purposes.

Although the contract was in effect until December 23, 1900, the city purchased the company in 1899 for the sum of $23,630. Once in control of the distribution system, including the pumphouse and intake, the just created Water Commission switched supply from the Assiniboine River to a series of artesian wells located to the northwest of the city. The water was highly corrosive, rendering it unsuitable for industrial purposes. City council realized that a softer and more secure source would soon be needed.

In 1906, the Water Commission was tasked to conduct a preliminary study on the feasibility of utilizing one of the many local and visible water sources. Sturgeon Creek and Roseau River were rejected as having poor potential for a long-term supply. Lake Manitoba was rejected because of the frequent storms experienced on the lake, while the springs were considered to be an extension to the artesian wells. The Winnipeg River emerged as the most reliable source, but further consideration was complicated by plans for a hydro project at Point du Bois.

A member of the Water Commission and co-founder of Manitoba Bridge and Iron Works, Thomas Deacon, suggested that Shoal Lake, situated near Kenora, was worthy of investigation.

On September 1, 1906, members of the Water Commission visited Shoal Lake. The party, consisting of chairman J.H. Ashdown, six commissioners including Deacon, the city controller and two newspaper reporters, travelled by steamer from Kenora through Lake of the Woods and into Shoal Lake. They found very little habitation. The shores of the lake were very steep and consisted of granite. There was no evidence of limestone that would indicate the presence of hard water. Soundings were taken and the depth at the centre of the lake  was estimated to be anywhere from 30 to 60 metres with a bottom of solid rock.

Despite the submission of a favourable report, Mayor Thomas Sharpe vetoed any consideration of Shoal Lake. He was convinced that potential jurisdictional and financial problems would be too great for Winnipeg to bear.

To aid in the search for a permanent water supply, the commission engaged the services of four consulting engineers — two from New York, one from Montreal — and the assistant chief engineer of the CPR. The consultants completed their survey on August 29, 1907.

Disregarding any reference to Shoal Lake, they proposed the Winnipeg River as the only feasible source for Winnipeg’s water supply. The Water Commission forwarded the report to council with a recommendation that it be adopted.

In the meantime, municipal elections were held and James Ashdown was elected mayor. Due to concern over the city’s financial position and the previous commitment to the development of a power plant on the Winnipeg River, the water question was shelved.

During the next few years, the city continued to expand. Building construction in the years following 1910, exceeded $83 million and this expansion, with a corresponding increase in population, was threatening the artesian well system’s ability to provide sufficient water.

With the completion of the hydroelectric project, the water question once again demanded council’s attention. Thomas Deacon continued to promote Shoal Lake as the only rational source for Winnipeg’s water.

Early in 1912, city council had attempted to pass a bylaw for the appropriation of $1 million to run a pipe line to Poplar Springs as an extension to the well system. It was defeated by the ratepayers. A board of consultants was then hired to evaluate a permanent water supply source.

Municipal elections were being held in December of that year and the leading issue was the water supply question. Thomas Deacon decided to run for the mayoralty advocating tapping the waters of Shoal Lake. Although opinion was divided on the issue, Deacon received media support and was elected mayor in December 1912. The consultants tendered their report in August 1913, recommending Shoal Lake as the most viable source.

The lake’s drainage area of approximately 736 square kilometres and being at the same level as Lake of the Woods, guaranteed a sufficient supply. Its quantity was estimated on the amount of rainfall in the area, and the size of the drainage area and of the lake’s surface.

One estimate put the quantity of water in a foot of the lake equivalent to eight months supply for a population of 850,000. Chemical analysis of the water revealed that the lake was free from any contamination, clear and pleasing to the taste due mostly to its rocky shoreline and remote location.

However, doubts were expressed as to its purity during the months of August and September. There was a fear that annual formations of microorganisms might occur, rendering the water unfit for human consumption and necessitating the construction of a filtration plant. But, it was decided that the size of the lake would make it unlikely such formations would occur. The water being much softer than well water, was also suitable for industrial purposes.

In order to organize and supervise a project of such magnitude, the Greater Winnipeg Water District was incorporated in September 1913 with a budget which would eventually grow in excess of $13 million. 

Through taxes, Greater Winnipeg Water District bond issues guaranteed by the provincial government and firm commitments from the banks, money was available to begin construction. However, jurisdiction and international obstacles did exist and required immediate attention.

A series of meetings were held between Manitoba and Ontario officials. Eventually, an agreement was reached allowing Winnipeg to proceed with a plan to tap the waters of Shoal Lake.

But, there was a more complex international barrier to be overcome. Great Britain and the United States had signed a waterways treaty on January 11, 1909 that created the International Joint Commission. The mandate of the IJC was to safeguard and regulate the levels of all waters shared by Canada and the U.S. Shoal Lake, being an extension of the Lake of the Woods which straddles the Canada-U.S. border, was designated a boundary water and therefore subject to the authority of the IJC.

The GWWD submitted its application to Ottawa and Washington on September 8, 1913, seeking approval for the diversion of Shoal Lake water to the city of Winnipeg. Ottawa backed the request.

The Town of Kenora, having a vested interest in the waters of Lake of the Woods, filed a petition on December 30 asking the commission to reject Winnipeg’s application. The basis of Kenora’s objection was: the diversion of Shoal Lake water would adversely affect levels, thus rendering the lake useless as a reservoir for regulating the level of Lake of the Woods; navigation, lumbering, resorts and other benefits to Kenora would be adversely affected; and Shoal Lake was not needed because there were other sources available.

The IJC convened on January 14, 1914 in Washington, D.C. In addition to the American members of the commission, including the United States War Department, representatives of Canada, Manitoba and Kenora were present. The IJC, after considering all the submissions, granted authority to GWWD to divert the waters of Shoal Lake to Winnipeg with the caveat that such waters were to be used for domestic and sanitary purposes only and never to exceed 450-million litres a day. The way was now clear for the construction of the Shoal Lake Diversion project.

The diversion was a challenging project, not only for the financial capability of a city of approximately 214,000, but for the construction technology of the time. It was planned to build the aqueduct entirely underground. No pumps would be required. With Shoal Lake’s elevation 90metres higher than Winnipeg, it would be a gravity-feed system.

The project would also require a railroad, approximately 160 kilometres in length, to transport men and equipment along the construction route and to gain access to the lake. For administrative and safety purposes, a complete telephone system was installed. Rivers and streams were crossed by tunneling under them.

Surveying for the right- of-way for the aqueduct and the GWWD railway was completed in October 1913. Railway construction began shortly thereafter. In December 1414, Mayor Deacon drove the last spike in the railway, and the first phase of the project was completed. The actual construction of the aqueduct commenced with the opening of tenders on September 19, 1914.

It was decided to build the intake on the shore of Indian Bay, an adjunct to Shoal Lake proper. The intake at Indian Bay required a gate house and pumping station. But before construction could begin, large boulders had to be removed by blasting. In order to preserve the quality of the lake water, a dike was built near the entrance of the bay to divert the waters of Falcon River.

The water entering the gate house would be regulated and screened for debris by the installation of two stainless steel mobile screens. Two giant diesel pumps were installed at the intake to be used if the lake declined to a level that would compromise gravity feed.

The aqueduct proper was built under the Whitemouth and Falcon rivers using inverted siphons. Maintenance crews would be able to enter the aqueduct by boat to conduct inspections.

Large quantities of rock were removed and muskeg swamps drained as construction progressed towards Winnipeg. At one point along the route, the engineers had to deviate from the surveyed route of the aqueduct because of poor soil conditions.

Working conditions were atrocious. The workers were often wet, muddy and cold as rain and snow filled the trench, forcing them to wade through knee-deep mud.

As the aqueduct neared the city, unstable earth conditions resulted in cave-ins and newly-constructed sections of the aqueduct sagged and cracked. At Mile 17, a concrete structure was installed which would divert excess water to a ditch leading to the Seine River.

The aqueduct was constructed in varying sizes dictated by the lay of the land and soil conditions. It was built in an arch-shape and in varying dimensions from 2.7-by-3.3 metres to 1.65-by-1.95 metres (nine-by-11 feet to 5 1/2-by-6 1/2 feet) in diameter. For the last 6.4 kilometres, before it reached its terminus at a reservoir about 21 kilometres from Winnipeg, it was a circular 2.4-metre (eight-foot) pipe. From there a water main, following the railway track, would carry the water to St. Boniface and into a wellhouse before proceeding into the city. It was necessary to tunnel under the Red River before entering the city proper.

When completed, the aqueduct would be able to carry 450 million litres of water a day, but the maximum output was never expected to exceed 382.5 million gallons. The volume of water required would never fill the aqueduct to the top.

Shoal Lake water reached Winnipeg on Thursday, March 27, 1919 when, at the western entrance to the Red River tunnel, a lever was thrown releasing the water into the last section of the aqueduct. Without fanfare or celebration, the diversion was officially proclaimed completed on Saturday, March 29. The city flushed out the artesian well water from the water mains on Sunday. The following day, March 31, Winnipeg finally had access to a new water supply.

The total cost, including the railway and telephone systems, was $15.3 million. This also included thousands of dollars spent on safety and security for the workforce. It was money well spent, as not one worker was seriously injured or killed during construction. The workers, although labouring under demanding conditions, were content and the project remained free of labour unrest or strike action.

Development prospects certainly looked optimistic in the spring of 1919. With a plentiful domestic water supply and the lowest hydro rates in the country, the local media predicted that industry would now consider Winnipeg as the ideal centre in Canada in which to locate.

Most municipalities wanted the railway to remain a public operation, and plans were made to run charter excursions to Indian Bay and Shoal Lake in the spring and summer months. Many organizations submitted applications for such excursions that year. (As recently as the 1970s, tours were conducted from Winnipeg to Indian Bay.) Expropriated land along the aqueduct right-of-way was released for development.

Over the years, additional reservoirs have been built to accommodate the demand of a growing city. If another aqueduct is required in the future, Shoal Lake will still remain the only viable source for Winnipeg’s water supply.