One of the most important points made by dam expansion opponents is that raising the dam will not create more water (in fact it will actually cause some water loss due to evaporation) but merely increases the capacity to store it.
水坝扩张反对者提出最重要的观点之一是，提高水坝不能增加水（实际上会因为蒸发而导致一部分水的损失），只会增加储水能力。