In most schools I know in the US and Canada, there is a school/college/faculty of Engineering that is separate from Arts and Sciences/Liberal Arts. Other separate colleges are typically smaller and specifically trade oriented, with cohorts of students taking many similar courses over their careers (i.e. Music or Education). Engineering, on the other hand, can house students studying Mechanical, Chemical, Civil, or Environmental engineering that may never take an engineering course together after their first year, and which work more closely with departments outside the college. How did Engineering become its own administrative division in universities?
"Universities" as we think of them through the 19th century were almost exclusively for the sciences/liberal arts, and were places almost exclusively for pedagogy, not research. They were places you would attend to become a lawyer, doctor, religious official, or (in Europe) a courtier. They were not a "hands on" education, and they were not at all focused on practical use of technology. Engineering education prior to the 19th century was mostly done through guilds and workplaces, through more of an apprenticeship model. There were a few institutions for studying engineering work, but they were primarily aimed at creating military engineers, or civil servants.
Over the course of the 19th century, this began to shift. One starts to see schools of civil engineering pop up, and universities themselves began to shift to the research-and-teaching model we now associate with them. But there were still cultural distinctions between the engineering faculties and those of the more traditional university colleges. Those liberal arts + sciences faculties are the nucleus of the original university model, with other, different modes (engineering schools, business schools, dedicated law schools, etc.) attached later in time.
Ultimately what you are seeing is the result of a historical evolution, and one of the more interesting ones in the history of science and technology: that for most of their histories, science and engineering have not been combined until relatively recently, and were done by distinct groups for different reasons.
In the latter-half of the 20th century, these barriers were broken down very methodically, and at most modern institutions the affinity lines are now between the humanities versus the STEM disciplines, as opposed to humanities + science vs. engineering, which is partially why it looks strange to us to have it organized the way it is. But again, this is actually a very recent development historically, and our institutions reflect that (universities are deliberately slow to change, as they are meant to last for centuries).
A really nice and concise survey of the history of engineering schools and engineering faculties is Anna Guagnini, "Technology," which is chapter 15 in Walter Rüegg, ed., A History of the University in Europe: Volume 3, Universities in the Nineteenth and Early Twentieth Centuries (Cambridge University Press, 2004). The American approach mirrored the changes already going on in Europe in the 19th century.