I said I wouldn't do it...
But now there is a widescreen post-compo version with improved UI, proper particle occlusion, and some water flow balance changes.
Show underlying terrain on focus...
Select multiple tiles and build many at once. This also works for dams and roads (not pictured). This does not allow building zoning tiles where you previously couldn't, only next to roads.
https://ldjam.com/events/ludum-dare/50/swimcity-2000