Read the following passage.
A. Hydroelectric power at Niagara started small. In the late 19th and early 20th centuries, the Niagara Falls area was home to many small hydro projects. The first major power plant on the Canadian side of the river, now called the Niagara Parks Power Station, drew its energy from the Horseshoe Falls and ran for 100 years. Water that had passed through the plant left by a tunnel about 2,200 feet long, 180 feet underground, and returned to the river at the base of the falls. Today the old station is open to visitors, who ride a glass elevator down to the tunnel.
B. The largest step came with a public project. In 1917, about 10,000 workers broke ground on the Queenston-Chippawa plant for Ontario Hydro, and soon afterwards they faced the Spanish Flu pandemic of 1918. The station began producing power toward the end of 1921. At 18 storeys high, it was then the largest hydroelectric station in the world. It was renamed Sir Adam Beck I in 1950 and has 10 units with a capacity of 446 megawatts. Its electricity helped power new household machines such as radios and washing machines, as well as the growing industries of Ontario.
C. The Sir Adam Beck stations now get additional water from the Niagara Tunnel. The world's largest hard rock tunnel boring machine dug it deep beneath the city of Niagara Falls. It is 12.7 metres wide and 10.2 kilometres long. The machine finished drilling in May 2011, and the tunnel was filled with water in March 2013. Gravity alone moves the water at 500 cubic metres per second to the Sir Adam Beck generating complex. Because of difficult rock, OPG and its contractor, STRABAG, agreed on a revised schedule in early 2009.
D. How much water the stations may use is set by an agreement between Canada and the United States. The 1950 Niagara Treaty requires at least 2,832 cubic metres per second to flow over the falls during the day from April 1 to October 31, and at least 1,416 at all other times. Water above these minimums is split equally between the two countries for hydropower. The International Niagara Board of Control oversees a control structure whose 18 sluice gates adjust the flow over the falls. It also oversees a floating ice boom that has been installed each winter since 1964 to reduce the ice entering the river.
E. Not given in any of the above paragraphs.
Decide which paragraph, A to D, has the information given in each statement below. Select E if the information is not given in any of the paragraphs.
AI explanationShows the answer. Tap to open.
Correct Answer: D
Why this is correct: Look at Paragraph D. The treaty sets a minimum flow over the falls. Water above these minimums is split equally between Canada and the United States for hydropower. Split equally means shared evenly.
Passage Reference: Water above these minimums is split equally between the two countries for hydropower.
Tips: Find the rule for water going over the falls. Then check how the rest is shared out, and who gets it.
Why the other options are wrong:
- A: Paragraph A talks about the Canadian side of the river. It never says how water is divided between countries.
- B: Paragraph B tells the story of a large public plant in Ontario. Sharing water with another country is not mentioned.
- C: Paragraph C gives the flow in the new tunnel, 500 cubic metres per second. It does not divide any water between countries.
- E: The equal split between the two countries is in Paragraph D, right after the treaty's minimum flows.
Correct Answer: A
Passage Reference: Water that had passed through the plant left by a tunnel about 2,200 feet long, 180 feet underground, and returned to the river at the base of the falls.
Why this is correct: Paragraph A describes the Niagara Parks Power Station. Water that had passed through it left by a tunnel 180 feet underground. It then returned to the river at the base of the falls.
Tips: Two paragraphs have tunnels. Ask which one carries water away after it is used.
Why the other options are wrong:
- B: Paragraph B gives the height and power of the Queenston-Chippawa plant. It says nothing about where used water goes.
- C: Paragraph C also has a tunnel, but that one brings water to the Beck stations. It does not return used water to the river.
- D: Paragraph D is about the flow that must go over the falls. It does not describe any tunnel.
- E: The old station's tunnel back to the river is described in Paragraph A.
Correct Answer: B
Passage Reference: In 1917, about 10,000 workers broke ground on the Queenston-Chippawa plant for Ontario Hydro, and soon afterwards they faced the Spanish Flu pandemic of 1918.
Why this is correct: Look at Paragraph B. About 10,000 workers broke ground in 1917. Soon afterwards they faced the Spanish Flu pandemic of 1918. A pandemic is a serious disease outbreak.
Tips: Paragraph C also has a problem during building. Look for one about health.
Why the other options are wrong:
- A: Paragraph A covers the small early projects and the first major plant. No illness is mentioned.
- C: Paragraph C mentions difficult rock as a problem for the tunnel. That was a problem with the ground, not with health.
- D: Paragraph D explains the treaty and the ice boom. Workers and illness are not part of it.
- E: The pandemic of 1918 is in Paragraph B, in the sentence about the 10,000 workers.
Correct Answer: E
Passage Reference: The world's largest hard rock tunnel boring machine dug it deep beneath the city of Niagara Falls.
Why this is correct: Paragraph B says about 10,000 workers started the plant in 1917. Paragraph C describes the Niagara Tunnel but never says how many people dug it. So the two cannot be compared.
Tips: A comparison needs two numbers. Check whether the tunnel has one.
Why the other options are wrong:
- A: Paragraph A is about the first plant on the Canadian side. It gives no workforce numbers.
- B: Paragraph B gives the number of workers for the 1921 plant only. The tunnel is not part of it.
- C: Paragraph C says a machine dug the tunnel. It never gives a number of workers.
- D: Paragraph D is about sharing the water. It says nothing about workers.
Correct Answer: C
Passage Reference: The machine finished drilling in May 2011, and the tunnel was filled with water in March 2013.
Why this is correct: Check the dates in Paragraph C. The machine finished drilling in May 2011. The tunnel was filled with water in March 2013. That is almost two years later.
Tips: Several paragraphs give years. Find the pair that belongs to the tunnel.
Why the other options are wrong:
- A: Paragraph A describes a much older tunnel below the first major plant. It gives no dates for digging or filling.
- B: Paragraph B has dates too, 1917 and 1921. Those are for building the plant, not a tunnel.
- D: Paragraph D gives the years 1950 and 1964. They are for the treaty and the ice boom.
- E: The two dates for the Niagara Tunnel appear together in Paragraph C.
Correct Answer: E
Passage Reference: It was renamed Sir Adam Beck I in 1950 and has 10 units with a capacity of 446 megawatts.
Why this is correct: Look at Paragraph B. The plant was renamed Sir Adam Beck I in 1950. The paragraph never says why it got that name. Nothing is said about money for it either.
Tips: A name and a reason for the name are two things. Look for 'because' next to the name.
Why the other options are wrong:
- A: Paragraph A is about the older Parks Power Station. Sir Adam Beck is not named there.
- B: Paragraph B gives the new name and the year. It does not explain the reason for the name.
- C: Paragraph C mentions the Sir Adam Beck stations but only as places that get water. No reason for the name is given.
- D: Paragraph D is about water limits and the ice boom. The plant's name is not discussed.
Correct Answer: A
Passage Reference: Today the old station is open to visitors, who ride a glass elevator down to the tunnel.
Why this is correct: Paragraph A ends in the present day. Today the old station is open to visitors. They ride a glass elevator down to the tunnel.
Tips: Find the earliest big plant on Canada's bank of the river. Check whether the public can tour it now.
Why the other options are wrong:
- B: Paragraph B calls the Queenston-Chippawa plant a public project. That means it was publicly owned, not open for tours.
- C: Paragraph C describes the tunnel under the city. Nobody visits it in the text.
- D: Paragraph D explains the treaty rules and the boards that manage water. Visitors are not mentioned.
- E: Visitors and the glass elevator are at the end of Paragraph A.
Correct Answer: C
Passage Reference: Because of difficult rock, OPG and its contractor, STRABAG, agreed on a revised schedule in early 2009.
Why this is correct: Look at the end of Paragraph C. Because of difficult rock, OPG and STRABAG agreed on a revised schedule in early 2009. Difficult rock is a problem with the ground.
Tips: Look for trouble with the ground under the city. Check what it made the tunnel builders change.
Why the other options are wrong:
- A: Paragraph A gives the depth of the old tunnel. It does not mention any delay.
- B: Paragraph B describes a hard start because of illness in 1918. It does not mention a new timetable.
- D: Paragraph D includes dates such as April 1 and October 31. Those are for water flows, not for building.
- E: Difficult rock and the new schedule close Paragraph C.
Correct Answer: B
Passage Reference: At 18 storeys high, it was then the largest hydroelectric station in the world.
Why this is correct: In Paragraph B, the plant began producing power toward the end of 1921. At 18 storeys high, it was then the largest hydroelectric station in the world. So no other station was as large.
Tips: More than one thing is called the biggest of its kind. Check which one was a plant driven by water, and when.
Why the other options are wrong:
- A: Paragraph A calls the older plant the first major one on the Canadian side. Being first does not make it the largest.
- C: Paragraph C says the boring machine was the largest of its kind. That is a machine, not a station.
- D: Paragraph D covers treaty flows and the ice boom. It makes no size comparison.
- E: This record is in Paragraph B, in the sentence about the 18 storeys.
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