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sample in December yielding 10,000 mg/i chlorides. Hawkins believes that deicing chemicals may also "be stored in the street itself, including: the snow and ice cover; on the street surface; and directly within the street masonry concrete, cobbles and o,ther stre,et construction materials." Observations of "summer leakage of salt" upward onto the stre,et s,urface, in ,areas which had been heavily salted the winter before, verified his beliefs. This resupply of salts continued through the summer rains and last,ed well into the autumn, continually finding their way into street and storm sewers. Several storm drainage areas in the Des Moines, Iowa study were evaluated for chlorides by Henningson, Durham, and Richardson, Inc,. (1973). The winter of ,1968~,69 ,which they examined was relatively severe, with large quantities of road deicing materials used. "Total deicers used, from December through March, were 8900 kg (9800 tons) with a chloride equivalent of 5300 kg (5830 tons)." A look at the results of one of the many storm drainage areas in the city shows the results of this heavy salting. A total of over 13,600 kg (15,000 Ibs) ~f chlorides were carried off between January 15 and March 2, in the runoff of a storm drain serving an area of 127 hectares (315 acres). Similar resul ts were seen in the other storm drainage ,areas throughout the city. The HDR study also reported that "samples of water from ,the Des Moines and Raccoon Rivers were significantly higher in the ,winter months than in the summer. Winter chloride values upstream of the city were in the 30~50mg/i range and downstream 18 ,