官方APP下载:英语学习播客(支持苹果手机、安卓手机)
创办于2003年
UNSV记不住?那就记中文谐音“忧安思危”吧!
  Slow and Steady Wins the Race!
UNSV英语学习频道 - Slow and steady wins the race!
公众微信服务号
英语全能特训(微信公众服务号)
UNSV英语学习频道淘宝网店
客服短信:18913948480
客服邮箱:web@unsv.com
初级VIP会员
全站英语学习资料下载。
¥98元/12个月

Ancient Water System in Peru Could Fix Water Shortages

作者:Alice Bryant 发布日期:7-8-2019

文章原文
同步字幕

Sometimes modern problems require ancient solutions.

A 1,400-year-old Peruvian method of diverting water could supply up to 40,000 Olympic-size swimming pools' worth of water to Lima each year. That information comes from a new study published in Nature Sustainability.

It's one example of how ancient methods could support existing modern ones in countries without enough water.

More than a billion people across the world face water shortages. Man-made reservoirs store rainwater and water overflow for use during drier times. But reservoirs are costly, require years to plan and can still fail to meet water needs. Recently, for example, the reservoirs in Chennai, India, went almost dry. The city's four million people had to then depend on water transports from the government.

Peru's capital, Lima, depends on water from rivers high in the Andes Mountains. It takes only a few days for water to flow down to the city. So when the dry season begins in the mountains, the water supply quickly disappears. The city suffers shortages of 43 million cubic meters during the dry season. It resolves this with modern structures such as man-made reservoirs.

View of the Andean highlands where Huamantanga is located. The city of Lima is located downstream in the horizon background.
View of the Andean highlands where Huamantanga is located. The city of Lima is located downstream in the horizon background.

These reservoirs are not the only solution, however. Over a thousand years ago, indigenous people developed another way to solve water problems.

Boris Ochoa-Tocachi is a researcher at Imperial College London and lead writer of the study. He explored one of the last remaining water-harvesting systems in the small mountain community of Huamantanga, Peru. The system was developed even before the ancient Inca civilization.

Water diverted, delayed

The 1,400-year-old system is designed to increase the water supply during the dry season by diverting and slowing water as it travels down the mountains.

This nature-based method is made of special canals that guide water from its source to a series of water bodies and hillsides. The water goes slowly into the ground, then flows downhill through the soil and reappears in water bodies near the community.

Its aim was to increase the water's travel time from days to months in order to provide water throughout the dry season.

But Ochoa-Tocachi said the amount of water that could be harvested was an unknown before the study.

The researchers measured how much the system slowed the flow of water by injecting special dye in the highlands and noting when it reappeared in water bodies. The dyed water started to surface two weeks later and continued flowing for eight months — a huge improvement over the hours or days it would normally take.

A stone water diversion canal system. The system increases the water's travel time from days to months to provide water throughout the dry season.
A stone water diversion canal system. The system increases the water's travel time from days to months to provide water throughout the dry season.

'I think probably the most exciting result is that we actually confirmed that this system works,' Ochoa-Tocachi said. 'It's not only trusting that, yeah, we know there are traditional practices, we know that indigenous knowledge is very useful." He said there is now proof the systems are valuable today and can be a tool to help solve modern problems.

Sizable increase in supply

The researchers next considered how using a larger version of the system could help Lima. They combined what they learned in Huamantanga with the knowledge of physical qualities of Lima's surroundings. The resulting estimates say the system could increase Lima's dry-season water supply by 7.5 percent overall and up to 33 percent at the start of the dry season. This amounts to nearly 100 million cubic meters of water each year — equal to 40,000 Olympic-size swimming pools.

Todd Gartner is director of the Natural Infrastructure Initiative at the World Resources Institute. He noted that this study 'takes what we often just talk about…and it puts this into practice." He said it does a lot of evaluation and observation and "puts real numbers behind it."

The system is also economically sound. Ochoa-Tocachi estimated that building canals similar to those in Huamantanga would cost 10 times less than building a reservoir of the same size. He also said former highland societies in other parts of the world had methods for diverting and slowing water flow. And, they could use these methods today to support their costlier modern methods.

'I think there is a lot of potential in revaluing these water-harvesting practices that have a very long history,' Ochoa-Tocachi said. He added that the idea of "using indigenous knowledge for solving modern engineering problems…is probably very valuable today.'

I'm Alice Bryant. And I'm Caty Weaver.

Kerry Hensley wrote this story for VOA News. Alice Bryant adapted it for Learning English.

Quiz - Ancient Water System in Peru Could Fix Water Shortages

Start the Quiz to find out

Start Quiz

Words in This Story

divertv. to change the direction or use of something

reservoirn. a usually man-made lake used to store water for use in people's homes, businesses and other places

indigenousadj. describing ethnic groups who are the original settlers to a specific region

canaln. a long narrow place that is filled with water and was created by people

dyen. a substance used for changing the color of something

actuallyadv. used to refer to something that is true or real

evaluationn. o judge the value or condition of (someone or something) in a careful and thoughtful way

potentialn. a quality that something has that can be developed to make it better

版权所有©2003-2019 南京通享科技有限公司,保留所有权利。未经书面许可,严禁转载本站内容,违者追究法律责任。 互联网经营ICP证:苏B2-20120186
网站备案:苏公网安备 32010202011039号苏ICP备05000269号-1中国工业和信息化部网站备案查询
广播台