As soon as people realized that their healt wos related to the environment they began to think out principless for improving it.
The Romans constructed aqueducts to prevent drought and to create a clean, healthful water supply for the metropolis of Rome.
In the 15th century, Bavaria created laws restricting the development and degradation of alpine country that constituted the region's water supply
In the mid-19th century in London Joseph Bazalgette designed the first major sewerage system
The field emerged as a separate environmental discipline during the middle third of the 20th century in response to widespread public concern about water and pollution and increasingly extensive environmental quality degradation. However, its roots extend back to early efforts in public health engineering
In many cases, as societies grew, actions that were intended to achieve benefits for those societies had longer-term impacts which reduced other environmental qualities. One example is the widespread application DDT (dichlorodiphenyltrichloroethane) to control agricultural pests in the years following World War II
Conservation movements and laws restricting public actions that would harm the environment have been developed by various societies for millennia. Notable examples are the laws decreeing the construction of sewers in London and Paris in the 19th century and the creation of the U.S. national park system in the early 20th century.