I have a very fast website, but there is one overview page that queries a lot and takes 16 to 17 seconds to load.
Will this have an impact on my SEO?
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Page speed is a ranking factor to some degree, as mentioned by Matt Cutts in this related video (Aug 2013): Is page speed a more important factor for mobile sites?.
However, pages are also ranked on their own merits. So that one page may not (should not) bring down the ranking of the other (fast) pages on your site (if that is what you are implying). But yes, that one page could rank lower because of its slowness to load.
How often does the information change - have you considered caching?