The elements of David Evans and Associates (DEA) can be classified as wind, land, and water. The engineering and architectural firm specializes in the sustainable design and the management of energy, land development, transportation, and water resource projects across the US. The firm also offers surveying services on land and in the water. DEA's projects include residential community development, heavy rail and highway design, energy facility design, and hydrographic surveys. Most of DEA's work is focused in the Pacific Northwest, but it has offices in Arizona, California, Colorado, Idaho, New York, Mississippi, Oregon, and Washington.