Since a lot of water is getting held up by the barrage, the incoming tides won't go as high, but they wouldn't be as low during low tide, either.

【翻译】由于大量的水被堤坝阻挡住，潮水不会涨到那么高，但在低潮时也不会那么低。

【分析】won’t和wouldn’t 两个情态动词，都表示“推测”。前者推测的可能性比后者要大一些，wouldn’t 不表示过去的意思。

两个as 都是程度副词，意为“那么；如此”，否定时可用so 代替。后面省略了已知的比较成分as...，具体省略了什么，前文一定提及，例如 as we imagine “跟我们想象的一样...”。