Any ground water will have more minerals than wain water. For example, the water delivered to my house has 450-550 mg/l TDS. A quick search shows that is about 10x higher than rain water [1].

[1] https://www.chaitanyaproducts.com/blog/rainwater-healthy-com...

My kitchen sink also doesn't get salted during the winter, the roads do. I wonder if someone at Tesla forgot that some areas rely heavily on salt to keep the roads ice free during the winter.

You don't use salt when cooking? :D

The concentration of salt in your cooking equivalent to the salt on the roads would make your food inedible.

It's probably not rainwater that's causing the rust. It's the water from the pavement, which does have higher mineral content, and might have corrosive substances, such as salt.

Rain water - sure. However rain water falls on the road, mixing with any minerals deposited on the road.

Woah! I had no idea they were pumping groundwater into the Capilano Reservoir. Thanks for the heads up

Isn't rainwater slightly more acidic than ground water?

We use rain water extensively in NZ tho

But as others answered - it's likely pitting from other sources, not elements themselves