更多灌溉系统 / More Irrigation
原版为了让五大湖通航做成了海，但是忘了这tm淡水湖凭什么不能修灌溉啊？
允许在北美五大湖、大运河建造灌溉系统及其类似物。
To allow you construct ship, vanilla make Great Lakes technically "sea", but they forget to allow construct irrigation system here, though those lakes are fresh lakes.
This mod allow you construct irrigation system and its analog in Great Lakes and Grand Canals.
