Damming the river may end up benefiting those who need it the least.

在河上建大坝最终可能有利于那些最不需要大坝的人。

《柯林斯英汉双解大词典》

When added to the effects from damming, irrigation and other water use, these changes could add up to a threat to future supplies of food and water.

如果再加上筑坝、灌溉、以及其它水资源利用的影响，这些变化会对这些地区未来的食物和水源供应构成威胁。

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The Fleet continues to wind its way north, ending up at Hampstead Heath, the ponds of which were actually formed by a damming of the river in the 18th Century.

BBC: In search of London's lost rivers