Far below every town and city lies an invisible network of pipes crucial to the lives of their residents. Once water disappears down a pipe or toilet, people rarely think about what happens to it. It’s out of sight, out of mind. The water flows into pipes that carry excess rainwater, wastewater and solid waste away, keeping the city clean.
There are three main types of sewers (下水道): sanitary (卫生的) sewers, storm sewers and combined sewers. Taipei has both sanitary and storm sewers where rainwater and sewage are collected using different pipes.
This sewer system functions as a city’s veins (静脉). Water containing human and industrial waste is collected in sanitary sewers and conveyed to sewage treatment plants, the heart of the sewer system, where waste is treated. There, the solid waste is separated from the water, which is then cleaned before being released back into the environment. It will be reused for industrial, agricultural or environmental purposes or to produce energy. Furthermore, the mud and gas from sewage treatment can be used to produce energy. They not only contribute to a healthy environment and good quality of life, but also achieve the goal of sustainable development.
While wastewater collection and treatment are critical to the health of urban residents, storm sewers also play an important role in the city. Green space has given way to concrete during the island’s rapid development and extensive building projects over the past few decades. As a consequence, there has been a loss of the land’s natural water as concrete cannot absorb rainwater. When an extreme weather event like a severe storm or typhoon brings heavy rain, storm sewers must cope with the water, so it does not flood the city. However, storm sewers are only part of the measures for water management and flood prevention.
To reduce flooding, an integrated urban drainage management plan has been adopted, where all the factors-storm sewers, land planning and economic development — are considered together. Engineering innovations, additional flood discharge facilities and increased green space requirements in new development projects have improved water maintaining in cities.
Who knew that sewers help improve urban public health, prevent urban flooding and boost environmental protection? Together they protect vital water resources and maintain the safety of people and property.
63. According to the passage, the word “
excess” in the first paragraph probably means______.
A.useless | B.polluted | C.extra | D.processed |
64. According to the passage, what does the city build two kinds of sewers for?
A.To test wastewater timely and to develop rapidly. |
B.To treat wastewater and to fight against flooding. |
C.To form a circulation and to clean the city. |
D.To clean wastewater and to manage water. |
65. What can we conclude from the passage?
A.What is unseen is as important as what is seen. |
B.There are three types of sewers in every city. |
C.People build sewer system because of concrete. |
D.Sewers are usually repaired every few decades. |
66. What would be the proper title for the passage?
A.A City’s Underground Construction |
B.A City’s Hidden Network |
C.How A City Operates Well |
D.Two Aspects of A City or Town |