The infrastructure in this period was pretty good the roads where 10 meters above the ground so they wouldn't get washed away when it was monsoon season. there was a lot of canals built in this time so the farmers had water to water their crops and make it faster to travel from one place to another. the poor people would have to live on wooden shacks on the river which were on stilts making these people the most vulnerable as if there was a monsoon most of the huts would be swept away, the richer people could afford houses on top of hills where they were less likely to be swept away.  most of the houses were made of bamboo and leaves.