ISSUES OF SCALE, GEOLOGY AND URBAN DEVELOPMENT

Planning for and implementation of urban development benefits from a knowledge of geology and geological processes and also from considerations of scale and location. The physiography and geology at the regional, local and site levels serve to organize and transfer relavent natural resource information for those who need to know. This talk explores three issues, water supply, aggregates, and natural hazards, in the Mid-Atlantic area of the United States. The area encompasses for physiographic provinces, Coastal Plain, Piedmont, Blue Ridge and Valley and Ridge, and include the ever-expanding Baltimore-Washington urban complex.

Water supply planning and development proceeds at regional scale (policy and priority setting), local scale (planning and design) and site scale (implementation) as illustrated by the Baltimore City water supply system.

Natural hazards also require evaluation at regional, local and site scales but relavence to a specific kind of hazard may vary depending upon the regional and local geology and physiography, for example, shoreline erosion, and sinkholes.

Aggregates differ as they are a local planning and policy issue as local zoning controls the location of quarries and their development. The occurrence and kind of aggregate (stone or sand and gravel, for example) depend, however, depend upon the geology at the regional, local and site levels.