TD&H Engineering; Thomas, Dean & Hoskins of Idaho Inc. Share: Business ServicesEngineers TD&H Engineering; Thomas, Dean & Hoskins of Idaho Inc. Visit Website 210 Main Street Lewiston, ID 83501 (208) 746-0938 (208) 746-3511 (fax) About About Civil engineering and surveying professionals specializing in transportation, general civil, structural, water, wastewater, geotechnical, and construction engineering.