Dirty River But Clean Water Reading Answers

Dec 19, 2022

Dirty River But Clean Water Reading Answers is a topic discussing about the rivers which are getting affected by the floods creating nuisance for the pupils. The given IELTS topic has been taken from the book called “Complete IELTS Bands 4-5 Student's Pack (Student's Book with Answers with CD-ROM and Class Audio CDs (2)”. There are 13 questions in total in the topic named Dirty River But Clean Water Reading Answers, which should be answered within the time span of 20 minutes by the candidates. Two types of questions are provided in the topic, which are, True/False/Not Given, and complete the summary. The candidates should read thoroughly the IELTS reading passage in order to recognize the synonyms and identify the keywords and for answering the questions below. Similar kinds of topics like Dirty River But Clean Water Reading Answers are included in the IELTS reading practice papers, which the candidates can take into their consideration for performing a good score in this section.

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Section 1

Read the Passage to Answer the Following Questions

Dirty River But Clean Water Reading Answers

Floods can occur in rivers when the flow rate exceeds the capacity of the river channel, particularly at bends or meanders in the waterway. Floods often cause damage to homes and businesses if they are in the natural flood plains of rivers. While riverine flood damage can be eliminated by moving away from rivers and other bodies of water, people have traditionally lived and worked by rivers because the land is usually flat and fertile and because rivers provide easy travel and access to commerce and industry.
Fire and flood are two of humanity’s worst nightmares. People have,therefore,always sought to control them. Forest fires are snuffed out quickly. The flow of rivers is regulated by weirs and dams. At least, that is how it used to be. But foresters have learned that forests need fires to clear out the brash and even to get seeds to germinate. And a similar revelation is now – dawning on hydrologists. Rivers – and the ecosystems they support – need floods. That is why a man-made torrent has been surging down the Grand Canyon. By Thursday, March 6th it was running at full throttle, which was expected to be sustained for 60 hours.
Floods once raged through the canyon every year. Spring Snow from as far away as Wyoming would melt and swell the Colorado river to a flow that averaged around 1,500 cubic metres (50,000 cubic feet) a second. Every eight years or so, that figure rose to almost 3,000 cubic metres. These floods infused the river with sediment, carved its beaches and built its sandbars.
However, in the four decades since the building of the Glen Canyon dam, just upstream of the Grand Canyon, the only sediment that it has collected has come from tiny, undammed tributaries. Even that has not been much use as those tributaries are not powerful enough to distribute the sediment in an ecologically valuable way.
This lack of flooding has harmed local wildlife. The humpback chub,for example, thrived in the rust-red-waters of Colorado. Recently, though, its population has crashed. At first sight, it looked as if the reason was that the chub were being eaten by trout introduced for sport fishing in the mid-20th century. But trout and chub co-existed until the Glen Canyon dam was built, so something else is going on. Steve Gloss, of the United States’ Geological Survey (USGS), reckons that the chub’s decline is the result of their losing their most valuable natural defence, the Colorado’s rusty sediment. The chub were well adapted to the poor visibility created by the thick, red water which gave the river its name and depended on it to hide from predators. Without the cloudy water, the chub became vulnerable.
And the chub are not alone. In the years since the Glen Canyon dam was built, several species have vanished altogether. These include the Colorado pike-minnow, the razorback sucker and the round-tail chub. Meanwhile, aliens including fathead minnows, channel catfish and common carp, which would have been hard, put to survive in the savage waters of the undammed canyon, have move din.
So flooding is the obvious answer. Unfortunately, it is easier said than done. Floods were sent down the Grand Canyon in 1996 and 2004 and the results were mixed. In 1996 the flood was allowed to go on too long. To start with,all seemed well. The floodwaters built up sandbanks and infused the river with sediment. Eventually, however, the continued flow washed most of the sediment out of the canyon. This problem was avoided in 2004, but unfortunately, on that occasion, the volume of sand available behind the dam was too low to rebuild the sandbanks. This time, the USGS is convinced that things will be better. The amount of sediment available is three times greater than it was in 2004. So if a flood is going to do some good, this is the time to unleash one.
Even so, it may turn out to be an empty gesture. At less than 1,200 cubic metres a second, this flood is smaller than even an average spring flood, let alone one of the mightier deluges of the past. Those glorious inundations moved massive quantities of sediment through the Grand Canyon, wiping the slate dirty, and making a muddy mess of silt and muck that would make modern river rafters cringe.

Section 2

Solution and Explanation
Questions 1-7

Do the following statements agree with the information given in Reading Passage?

In boxes 1-7 on your answer sheet, write

TRUE, if the statement agrees with the information
FALSE, if the statement contradicts the information
NOT GIVEN, if there is no information on this

Damage caused by the fire is worse than that caused by the flood.

Answer: Not Given
Explanation: No pertinent information regarding the above said sentence is available in the passage.

The flood peaks at almost 1500 cubic meters every eight years.

Answer: False
Supporting sentence: Spring Snow from as far away as Wyoming would melt and swell the Colorado river to a flow that averaged around 1,500 cubic metres (50,000 cubic feet) a second.
Keywords: Every eight years, almost 3,000 cubic metres
Keyword location: Paragraph C
Explanation: Paragraph C states that the canyon used to see yearly floods. Spring snow would melt and swell the Colorado River to an average flow of 1,500 cubic metres (50,000 cubic feet) per second from as far away as Wyoming. That amount increased to roughly 3,000 cubic metres every eight years or so. These floods sculpted the river's beaches, added silt, and constructed its sandbars. So, the statement is regarded is False.

Contribution of sediments delivered by tributaries has little impact.

Answer: True
Supporting sentence: However, in the four decades since the building of the Glen Canyon dam, just upstream of the Grand Canyon, the only sediment that it has collected has come from tiny, undammed tributaries. Keywords: Sediment that it has collected has come from tiny, undammed tributaries, not been much use
Keyword location: Paragraph D
Explanation: Paragraph D in the passage enhances that only silt that the Glen Canyon dam, which is located directly upstream of the Grand Canyon, has gathered in the four decades since it was built, is from minor, undammed rivers. Even that has not been much use because those tributaries lack the strength to spread the sediment in a way that is beneficial to the environment. Thus, the sentence is True.

The decreasing number of chubs is always caused by introducing of trout since the mid 20th century.

Answer: False
Supporting sentence: Steve Gloss, of the United States’ Geological Survey (USGS), reckons that the chub’s decline is the result of their losing their most valuable natural defence, the Colorado’s rusty sediment.
Keywords: created by the thick, red water
Keyword location: Paragraph E
Explanation: Paragraph E explains that the loss of the chub's most important natural defence, the rusty sediment of Colorado, according to Steve Gloss of the United States Geological Survey (USGS), is what led to their collapse. The chub, which gave the river its name and relied on it to hide from predators, were well adapted to the poor visibility provided by the thick, red water. The chub was exposed without the murky water. It was once thought that trout introduced for sport fishing in the middle of the 20th century were consuming the chub. Therefore, it is a False statement.

It seemed that the artificial flood in 1996 had achieved success partly at the very beginning.

Answer: True
Supporting sentence: In 1996 the flood was allowed to go on too long.
Keywords: 1996 the flood, go on too long
Keyword location: Paragraph G
Explanation: Paragraph G states that the Grand Canyon experienced artificial floods in 1996 and 2004, which first appeared to be quite successful. Thus, this started in 1996, and the second fake flood occurred in 2004. The sandbanks were created during the 1996 flood, which was lengthier in duration. It also introduced a great deal of sediment to the river. So, in terms of the information in the passage, this assertion is accurate. Thus, it is regarded as a True sentence.

In fact, the yield of artificial flood water is smaller than an average natural flood at present.

Answer: True
Supporting sentence: At less than 1,200 cubic metres a second, this flood is smaller than even an average spring flood, let alone one of the mightier deluges of the past.

Keywords: flood is smaller, average spring flood,
Keyword location: Paragraph H
Explanation: The paragraph H in the passage suggests that with a flow rate of less than 1,200 cubic metres per second, this flood is considerably lower than both the typical spring flood and even some of the more powerful downpours in history.

Mighty floods drove fast-moving flows with clean and high-quality water.

Answer: Not given
Explanation: No available information has been provided in the above context to justify the validity of this sentence.

Questions 8-13

Complete the summary below.

Choose NO MORE THAN TWO WORDS from the passage for each answer. Write your answers in boxes 8-13 on your answer sheet.

The eco-impact of the Canyon Dam

Floods are people’s nightmare. In the past, the canyon was raged by flood every year. The snow from far Wyoming would melt in the season of 8…………………… and caused a flood flow peak in Colorado river. In the four decades after people built the Glen Canyon Dam, it only could gather 9…………………… together from tiny, undammed tributaries.

Question

Answer: Spring
Supporting sentence: Spring Snow from as far away as Wyoming would melt and swell the Colorado river to a flow that averaged around 1,500 cubic metres (50,000 cubic feet) a second.
Keywords: Spring Snow, far away, Wyoming, melt and swell, Colorado river, flow
Keyword location: Paragraph C
Explanation: The paragraph C explains that the canyon once saw yearly floods. Spring snow would melt and swell the Colorado River to an average flow of 1,500 cubic metres (50,000 cubic feet) per second from as far away as Wyoming. That amount increased to roughly 3,000 cubic metres every eight years or so. These floods sculpted the river's beaches, added silt, and constructed its sandbars.

Question

Answer: Sediment
Supporting sentence: However, in the four decades since the building of the Glen Canyon dam, just upstream of the Grand Canyon, the only sediment that it has collected has come from tiny, undammed tributaries.
Keywords: the only sediment that it has collected has come from tiny, undammed tributaries
Keyword location: Paragraph D
Explanation: The paragraph D in the passage describes that in the four decades since it was built, the Glen Canyon dam, directly upstream of the Grand Canyon, has only accumulated material from minor, undammed rivers. Even that has not been much use because those tributaries lack the strength to spread the sediment in a way that is beneficial to the environment.

Humpback chub population on reduced, why?

Then, several species disappeared including Colorado pike-minnow, (10)…………………… and the round-tail chub. Meanwhile, some moved in such as fathead minnows, channel catfish and (11)……………………. The non-stopped flow led to the washing away of the sediment out of the canyon, which poses a great threat to the chubs because it has poor (12)…………………… away from predators. In addition, the volume of (13)…………………… available behind the dam was too low to rebuild the bars and flooding became more serious.

Question

Answer: Razorback sucker
Supporting sentence: These include the Colorado pike-minnow, the razorback sucker and the round-tail chub.
Keywords: Colorado pike-minnow, the razorback sucker and the round-tail chub
Keyword location: Paragraph F
Explanation: Paragraph F in the passage enhances that since the construction of the Glen Canyon Dam, some species have completely disappeared. These include the razorback sucker, round-tail chub, and Colorado pike-minnow.

Question

Answer: Common Carp
Supporting sentence: Meanwhile, aliens including fathead minnows, channel catfish and common carp, which would have been hard, put to survive in the savage waters of the undammed canyon, have move din.
Keywords: aliens including fathead minnows, channel catfish and common carp
Keyword location: Paragraph F
Explanation: The paragraph F states that the untamed waters of the canyon have attracted alien species including fathead minnows, channel catfish, and common carp that would have had a difficult time surviving.

Question

Answer: Visibility
Supporting sentence: The chub were well adapted to the poor visibility created by the thick, red water which gave the river its name and depended on it to hide from predators.
Keywords: poor visibility, thick, red water, vulnerable
Keyword location: Paragraph E
Explanation: The paragraph E explains that the thick, red water that gave the river its name and on which the chub depended to hide from predators was well adapted to the poor visibility provided by it. The chub was exposed without the murky water.

Question

Answer: Sand
Supporting sentence: Eventually, however, the continued flow washed most of the sediment out of the canyon. This problem was avoided in 2004, but unfortunately, on that occasion, the volume of sand available behind the dam was too low to rebuild the sandbanks. This time, the USGS is convinced that things will be better.
Keywords: volume of sand available, too low
Keyword location: Paragraph G
Explanation: Paragraph G in the above context implies that most of the material in the canyon washed out by the ongoing flow. Fortunately, in 2004, the issue could have been prevented because there was enough sand behind the dam to rebuild the sandbanks. The USGS is certain that things will turn out better this time.

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