美国还有9.1万个水坝,中国有9.8万个, 欧洲国家有1.2million 水利设施。 非洲据说有1000个左右大坝

There are over 91,000 dams in the US, with some estimates reaching over 500,000, many of which provide benefits like flood control, water supply, and hydroelectric power. Despite the large number of dams, many are aging, deteriorating, and no longer serve their original purpose, leading to safety hazards and environmental concerns that prompt ongoing efforts to repair or remove them. 
 
Why we still need dams
  • Flood control: Dams help prevent flooding by holding back excess water and releasing it in a controlled manner.
  • Water supply: They act as reservoirs, storing water for drinking, agriculture, and industrial use.
  • Hydropower: Many dams generate electricity through turbines, providing a source of renewable energy.
  • Irrigation: Dams supply water for agricultural irrigation, which is crucial in many parts of the country.
  • Navigation: They create or maintain navigable waterways for commercial and recreational boats.
  • Recreation: The reservoirs created by dams are often used for recreational activities like boating and fishing. 

 

China has over 98,000 dams, and they are still needed for hydropower, flood control, and water security, though climate change and dam management present new challenges. These dams are crucial for generating electricity, providing water for agriculture and industry, and preventing catastrophic floods, which have historically caused immense damage along major rivers. However, the construction of numerous dams, particularly the mega-dams, has had negative environmental impacts. 

 

 

 

here are likely between 600 and 800 large dams in Africa, though a precise number is difficult to confirm. Dams are still needed for crucial functions like irrigation, providing clean drinking water, and generating hydropower, which is a key source of renewable energy for many countries. However, building dams is often controversial due to negative impacts like development-induced poverty, social displacement, and inequitable distribution of benefits. 
 
How many dams are in Africa?
  • The exact number is not definitively known, but estimates for large dams and reservoirs range from 600 to 800.
  • One source states there are over 1,270 large dams in Africa, but this number may be less up-to-date or use a different definition. 

所有跟帖: 

大坝数量也是国家实力的指标之一。说大坝破坏环境的人就像说建房子破坏环境一样,他们应该住山洞里,那样最保护环境。 -为人父- 给 为人父 发送悄悄话 为人父 的博客首页 (167 bytes) () 11/11/2025 postreply 13:43:52

要绝对环境保护,可以考虑自戕, -大洋bridge- 给 大洋bridge 发送悄悄话 大洋bridge 的博客首页 (0 bytes) () 11/11/2025 postreply 13:48:20

根据西方学者的数据,人是最大的环境破坏者。没人了,地球生态就会恢复如初。 -为人父- 给 为人父 发送悄悄话 为人父 的博客首页 (321 bytes) () 11/11/2025 postreply 13:55:08

AOC说现在牛放屁都是问题。climate change是主党的主题。有问题可以请教他们 -Uusequery- 给 Uusequery 发送悄悄话 (167 bytes) () 11/11/2025 postreply 13:55:48

我觉得你们的观点和民主党差不多,都反对建大坝,说大坝破坏环境。 -为人父- 给 为人父 发送悄悄话 为人父 的博客首页 (167 bytes) () 11/11/2025 postreply 14:04:17

几时说到反对建大坝,只是提到美国近年来在拆大坝。说说民主党如何反对建大坝?美国近年讨论过修水坝? -Uusequery- 给 Uusequery 发送悄悄话 (325 bytes) () 11/11/2025 postreply 14:08:01

拆不拆是有经济考量的,美国的大坝大部分都是老化严重,有的早该拆却因为没钱拆不了,直到被洪水冲垮反而成了比较省钱的办法。 -dakinglaile- 给 dakinglaile 发送悄悄话 dakinglaile 的博客首页 (0 bytes) () 11/11/2025 postreply 14:21:04

每条河流上能建水电站的坝址是固定有数的,美国从建国到现在,能建设且有经济效益的坝址早都建了,所以基本没有新建的需要。 -天青水蓝- 给 天青水蓝 发送悄悄话 天青水蓝 的博客首页 (0 bytes) () 11/11/2025 postreply 14:22:55

现在拆除的都是年代比较久远,年久失修有溃坝危险的,如果在洪水中被冲垮,会给下游带来危险,主动拆除可以避免这种危险 -天青水蓝- 给 天青水蓝 发送悄悄话 天青水蓝 的博客首页 (0 bytes) () 11/11/2025 postreply 14:25:05

明州前两年被冲垮的一个就是因为没钱拆才拖到洪水冲的。 -dakinglaile- 给 dakinglaile 发送悄悄话 dakinglaile 的博客首页 (0 bytes) () 11/11/2025 postreply 14:36:20

不建的理由就更多了。毕竟过去百年里美国先辈们早就把能建的都建了一遍了。现在环保要求和建造费用这么高,想建个新的难如登天。 -dakinglaile- 给 dakinglaile 发送悄悄话 dakinglaile 的博客首页 (0 bytes) () 11/11/2025 postreply 14:23:29

请您先登陆,再发跟帖!