I was changing pollen filter on my Astra G, and when i opened filter box a lot of water came out if it. I have air conditioneng, and i asume that the water is condensate from air conditioning, and probobly there is some drainage pipe , that is blocked up, but i cant find whre it is and how to clean it.

hope to get some info asap , since i dont whant to mess up my new pollen filter by placing it back to that wet place