[OrganicH2O]

For a tertiary halide+ethanol, compared to a tertiary halide + water, should one expect this to change the Sn1/E1 ratio significantly?

I saw in the answers to a problem set that a tertiary halide + ethanol was giving E1 as the major product, and the exact same tertiary halide + water was giving Sn1 as the major product. Is there any reasoning for this, or was the person who wrote this answer key just senile? There was no mention of temperature, so I guess assume room temperature.

Perhaps water is a slightly stronger nucleophile, and I'm not sure at all of the thermodynamics of it. I haven't seen this logic used in any textbook.