Petty Harbour Generating Station

The Petty Harbour Hydro Electric Generating Station is a hydroelectric generating station in Petty Harbour–Maddox Cove, Newfoundland and Labrador. It was constructed in 1898 and it was the first hydroelectric generating station in Newfoundland. It was built by the St. John's Street Railway Company, a company established by Robert Reid. Operation commenced on 19 April 1900.
In 1920 Reid renamed the company the St. John's Light and Power Company. On 7 February 1921, an avalanche destroyed of the wooden penstock that carried water from the dam to the generating station, cutting off all electrical power to St. John's for almost five days. Then, in 1924, the plant changed ownership to the Royal Securities Corporation of Montreal, where they began extensive reconstruction of the plant and watershed area. 
On 1 May 1978, the plant was entered in the Canadian Engineering Heritage Record as a model reflecting progressive adaptation to emerging technology, and remains today as one of the few plants of its type still in active service.
General Information.
Location: Petty Harbour-Maddox Cove, Newfoundland and Labrador<br>Owner: Newfoundland Power<br>Capacity: 5.3 MW<br>Average Yearly Output: 18 gigawatt-hours<br>Head: 57.9 metres<br>Average Streamflow: 5.6 cms<br>On-Line: 1900<br>Original Design: G.H. Massey, A.C. Rice<br>Original Construction: Reid Newfoundland Company
Equipment.
Turbines.
Unit 1: (installed in 1902)
Inward-flow Girard type (impulse turbine)
1.4 MW
Manufactured by Stillwell, Bierce & Smith
Vaille Co.
Replaced in 1912 with
Horizontal Francis turbine
1.57 MW
Manufactured by Voith<br>
Unit 2: (installed in 1900) Victor type (early Francis turbine)
1.4 MW
Manufactured by Stillwell, Bierce & Smith
Vaille Co.
Replaced in 1908 with
Horizontal Francis
1.57 MW
Manufactured by Voith<br>
Unit 3: (installed in 1926)
Horizontal Francis
2.05 MW
Manufactured by Armstrong Whitworth
Generators.
Unit 2 (installed in 1900):
3-phase, 60 Hertz, 550 volts
Manufactured by Westinghouse
Replaced in 1926 with 
3-phase, 60 Hertz, 2,300 volts
Manufactured by General Electric<br>
Unit 1 (installed in 1902):
3-phase, 60 Hertz, 550 volts
Manufactured by Westinghouse
Rewound in 1926 to 2,300 volts<br>
Unit 3 (installed in 1926):
3-phase, 60 Hertz, 2,300 volts
Manufactured by General Electric
Construction.
Powerhouse.
48.8 metres long by 7.3 metres wide
by 4.9 metres high
Masonry construction
Penstock.
Original:<br>
1,057 metres long, 2.4-meter by 2.4-meter
cross-section wooden flume<br>
112.2 metres long, 2.4-meter by 2.4-meter
cross-section rock tunnel<br>
115.2 metres long, 2-meter-diameter
steel penstock<br>
Replacements:<br>
1926: 975-metre-long, 2.3-meter-diameter
wood stave penstock<br>
1953: Steel penstock (surge tank riser)
replaced with 2.3-metre-diameter
steel pipe<br>
1999: Lower 740.7 metres of penstock
replaced with 2.3-metre-diameter
steel pipe<br>
Intake Structure:<br>
Concrete with steel gate and lift
(integral to forebay dam)<br>
Dams & Reservoirs.
Forebay.
In 1900, rockfill with timber facing.
Replaced in 1926 with concrete gravity.
Steel anchors added in 1992.
9.1-meter maximum height.
Bay Bulls Big Pond.
Zoned earthfill (rebuilt 1998–1999)
Concrete outlet conduit
Cochrane Pond.
Earthfill with concrete overflow spillway
and timber crib outlet
Tailrace.
Unlined canal excavated in rock
137 metres long