An overabundance of something is an inundation. If you got an inundation of requests for your famous chocolate cupcakes, you better get baking!
If you advertised a free piano in the local newspaper, you might get an inundation of emails in response, and your picnic on the grass could be ruined by an inundation of ants. Inundation can also refer specifically to a flood of water, like when a riverbank is at risk of inundation after several days of heavy rain. This makes sense as the root word in Latin is inundationem, "an overflowing."