At Western, there is not a lot of drug use, other than marijuana. Typically, most students will drink more than they will use drugs. In fact, people who do anything harder than marijuana are very rare. The amount of marijuana use throughout the University is spread out among groups; however, it is not uncommon to see someone smoking a joint near a party.
If you do not like drug use, avoiding the types of people who do these drugs is possible. There are so many students at the University that picking the types of people you like to hang out with is easy.