How does water sensor work with standard (non-interactive) monitoring

I was thinking of getting a Simplisafe water sensor (this is for a 3rd generation system) for an upstairs closet water tank and I currently have a standard $15/month non-interactive contract. What notification if any will I get if the water sensor goes off? Do I need to have the interactive $25/month contract to get a text or email? And if I don't get a notification by email or text, what happens, just a local alarm from the sensor itself?

I could not find this information online from the Simplisafe webpages or when trying to search the forums.