 A civil engineer is a person who practices civil engineering, the application of planning, designing, constructing, maintaining, and operating infrastructure while protecting the public and environmental health, as well as improving existing infrastructure that have been neglected. Civil engineering is one of the oldest engineering disciplines because it deals with constructed environment including planning, designing, and overseeing construction and maintenance of building structures and facilities such as roads, railroads, airports, bridges, harbors, channels, dams, irrigation projects, pipelines, power plants, and water and sewage systems. The term civil engineer was established by John Smeden in 1750 to contrast engineers working on civil projects with the military engineers, who worked on armaments and defenses. Over time, various sub-disciplines of civil engineering have become recognized and much of military engineering has been absorbed by civil engineering. Other engineering practices became recognized as independent engineering disciplines, including chemical engineering, mechanical engineering, and electrical engineering. In some places, a civil engineer may perform land surveying. In others, surveying is limited to construction surveying, unless an additional qualification is obtained.