You will see some flooding at first but it will go away, like I said pay attention and do not overload areas, think about what you are placing and where. Even railways are preinstalled on this map and everything is well thought out. I have built on this 3 times already, it is a fun map. All you have to do is place down stations and enjoy.

https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=2681206073 right here, you don't even have to build roads or metro tracks (all built in), but be careful traffic can get sticky if you don't pay attention to what you are putting in and where you put items. This city is now over 300k and climbing.

Beautiful! Which map is this?

=-)

Wow