A state-of-the-art review is presented of highway deicing practices and associated environmental effects. The bare pavement policy has resulted in a great increase in the use of deicing salts, but excessive application is leading to environmental problems. Besides chemical melting, various methods for deicing are discussed in this article. Salt storage facilities often become a major contributing source of local groundwater and surface water salt contamination. Coverage of salt piles is becoming more prevalent. Types of enclosed structures are illustrated, and cost considerations given. High chloride concentration levels have been found in roadway runoff. The special additives in deicing salts may create more severe pollutional problems than the chloride salts. Widespread damage of roadside soils and vegetation has been observed in areas of liberal salt usage.