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The Main Dam

Grand Lake, Near Howley

The Main Dam was an incredible engineering achievement when it was built nearly 90 years ago. The dam is an Ambersen style, diversion dam, which holds up 8 million cubic metres of water in Grand Lake. Its purpose is to raise water levels on Newfoundlands largest lake causing the water to channel through an 11 km canal to the Deer Lake Hydro Electric Station where power is created for the Corner Brook Pulp and Paper Mill. 

The Dam and Its History

In 1922 the Newfoundland Power and Paper Company made the decision to build a pulp and paper mill in Corner Brook. When completed in 1925 the Corner Brook mill was the largest of its kind in the world. In order to power the large paper making machines, the company would also need a large power source. So in 1922 the company hired  Sir W.G. Armstrong Whitworth and Company ltd to build a Hydroelectric station at Deer Lake. Construction for the hydro generating station, canal and dam began in 1922 and on August 24, 1925, the 125 Mega Watt Deer Lake Hydro Electric Station was officially opened. 

The dam is 225.6 metres wide and 23.3 metres tall. Eighteen, 4.7 metre wide steel gates span the length of the dam and are opened by one of the two gantry canes located on top of the dam. When opened the dam can spill 1840 cubic metres of water per second into the Junction Brook Spillway. When opened water falls down designated water ways on the front of the dam before being deflected back up into the air by "deflectors", which prevents erosion from occurring at the base of the dam. Inside the dam are two walkways that are accessed by metal doors in the side of the dam(sadly these are locked and cannot be accessed). 


When water levels in Grand Lake raised, the landscape of the area drastically changed. Most of the old railway between Howley and Deer Lake was flooded and had to be redirected over the top of the dam. The raising of the water also is said to have connected Grand Lake and Sandy Lake by stopping the flow of a small river, known as Main Brook that flowed between the lakes. Grand Lake has also been believed to once of had a large Beothuk Presence along its shores. However with the flooding of the lake its possible and believed that many important archaeological sites were lost.

A Haunting

Around 3000 people were believed to be hired during the construction of the hydroelectric station. Over the years some of the people who built the dam and have visited it since then have claimed to have seen a ghost or spirit that haunts the dam. In Dale Jarvis' book, Haunted Waters, is the story of a worker named Sam who fell into the freshly laid concrete of the dam and where he became trapped and died. There are several versions of the story but each ends with his remains still being in the dam today. 

Today and Getting There

The dam is still used to supply power today to the Corner Brook Pulp and Paper Mill. The gates of the dam are opened every now and again when water levels in the lake get to high. When they're open it is a very unique, exciting, and powerful thing to see. 


Getting to the Main Dam isn't incredibly difficult but it is not easy all the same.The Newfoundland T'Railway, which is a cross province dirt road that follows the old Newfoundland Railway, now passes by the dam, so by walking, driving or snowmobiling on this dirt road will eventually get to it. The Newfoundland T'Railway can be accessed from Deer Lake or Howley. Howley being the entrance much closer to the dam. 


Since the dam is still used and maintained, a service road starting at the hydro plants water intakes in Deer Lake is used by employees to reach the dam but is blocked off from use by large vehicles. Although signs warn that the road is off limits, Atvs and dirt bikes are able to pass by many of the gates. 


Another way of access is to hike or snowshoe across Molly Anns Bog. To do this you walk from the Crooked Feeder bridge, east of Deer Lake on the TCH and walk south over the bog until you reach the T'Railway or the Dam itself. This is the shortest route to take distance wise but the bog can be very strenuous to cross in the summer. During the winter it offers an excellent place to snowshoe because of the beautiful scenery, caribou heards, and other wildlife that live on the bog. 

Sources & Further Exploring

Smallwood, J. R., & Pitt, R. D. W. (1981). Encyclopedia of Newfoundland and Labrador. St. John's, N.L.: Newfoundland Book Publishers. (Article: “Deer Lake”. Available online through the Centre for Newfoundland Studies collections database)


Visit the Corner Brook Museum and Archives located at 2 West Street in the city of Corner Brook.

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