An Englsih Student going to University in Holland?

I'm not sure but personally I think one year is a bit short to really learn the Dutch language, especially if you won't be in an environment with native speakers. You might be able to understand and speak at a basic level, but don't forget that your coursework will all have to be written in the Dutch language at university level. Dutch may seem like an easy language but it is actually on of the hardest european languages to learn due to the many grammatical rules and exceptions to those rules we have.

That being said, there are a lot of international students in Amsterdam as well as tourist and everyone is quite used to English speaking people so socially it shouldn't be any problem. The Universiteit van Amaterdam (don't know if you want to go to the UvA or the VU?) offers a Dutch as a second language course for international students and they say it takes approximately a year, but of course this is in a Dutch environment so that is very likely to speed up the process of learning the language. Anyway, you probably already saw this but they have a page on language requirements right here.

If you can find a way to make it work I would definitely say go for it though, Amsterdam is a lovely city if it suits you and studying abroad is a great experience