For the Millennium Challenge, ASCE canvassed its members in late 1999 to determine the 10 civil engineering achievements that had the greatest positive impact on life in the 20th century. Rather than individual projects, they chose to recognize broad categories of achievements.
ASCE's members ranked the 10 greatest civil engineering achievements as:
Airport Design And Development
The Interstate Highway System
Sanitary Landfills/Solid Waste Disposal
Water Supply and Distribution
The American Society of Civil Engineers polled its membership to rank the ten civil engineering achievements that had the “greatest positive impact on life in the 20th century.” Those achievements are featured in the Monuments of the Millennium exhibit, and include Airport Design And Development, Dams, The Interstate Highway System, Long-Span Bridges, Rail Transportation, Sanitary Landfills/Solid Waste Disposal, Skyscrapers, Wastewater Treatment, Water Supply and Distribution, and Water Transportation. There is an introduction for each section, accompanied by a highlighted national or international project with images and links for more information. The site is small, but has a good overview the types of projects ASCHO members believe to be the most significant public works of the past century.