Answer:
The phrase "With all this rain, we will have to build an ark, if we want to get to work" refers to the biblical passage of Noah and his ark, through which the biblical prophet was entrusted by God to create an ark in which to keep two animals of each species and his family, to survive a great rain that would be sent by God to punish men for their wickedness.
So the phrase refers allegorically to the fact that, in a great flood, workers must get an ark in order to get to work.