Waterways and construction

[jophbot]

Making further use of waterways:

Lumber mill - churn those logs into boards. I would also suggest being able to use logs as rafts, for transportation on the river, but only move at walk speed, and no carry capacity, although you could band x logs together with rope for transit of multiple logs at a time.

irrigation - dig a trench, or have it skill based, whatever, from a waterway to a tile adjacent to a field to provide a bonus to quantity/quality/speed/influence/all of the above/dependent upon biome, whichever deemed most appropriate.