As early as the 1960s, there was a growing awareness that the resources of the Chesapeake Bay watershed were declining largely due to the tremendous pressure placed upon sensitive resources by a rapidly expanding population. In response to concerns about the quality and productivity of the Chesapeake Bay, the General Assembly enacted a comprehensive resource protection program for the Bay and its tributaries.

The Critical Area Act, passed in 1984, was significant and far-reaching, and marked the first time that the State and local governments jointly addressed the impacts of land development on habitat and aquatic resources.

The law identified the "Critical Area" as all land within 1,000 feet of the Mean High Water Line of tidal waters or the landward edge of tidal wetlands and all waters of and lands under the Chesapeake Bay and its tributaries. The law created a statewide Critical Area Commission to oversee the development and implementation of local land use programs directed towards the Critical Area that met the following goals:

• Minimize adverse impacts on water quality that result from pollutants that are discharged from structures or conveyances or that have run off from surrounding lands;
• Conserve fish, wildlife, and plant habitat in the Critical Area; and
• Establish land use policies for development in the Critical Area which accommodate growth and also address the fact that, even if pollution is controlled, the number, movement, and activities of persons in the Critical Area can create adverse environmental impacts.