While I'm not in engineering, I knew a lot of people in first year who were. As you probably know already, the first year engineering course load is much heavier than other faculties. This compounded with the fact that University is very different and often harder than what you were used to in high school might cause the majority of your time to be consumed already.
However, you shouldn't turn your back on extra-curriculars. I'd suggest joining the Rowing team if that's something you enjoy, as it will act as a good balance from your school work. At the end of the day, I'm sure you'll be able to manage it along with your course work as long as you don't slack off a lot!