Streets are prioritized for salting and snow plowing operations based on traffic volume, public transportation routes, access to emergency services and schools.

Operations does not automatically apply a uniform amount of salt throughout the city; salt is applied only where it is needed and in an amount appropriate for conditions. Salt may be applied only to the main streets, or only to bridges, hill stops, major intersections or slippery areas. Salt application rates are reduced on side streets.

Truck-mounted salt spreaders carry microprocessor-based controls which adjust the salt spread rate to changes in truck speed. This makes it possible to apply salt uniformly in urban stop-and-go traffic. Also, a mix of liquid calcium chloride and rock salt is used when temperatures are at 25 degrees or below because it makes the salt more effective.

Although the use of abrasives like sand instead of salt can be effective in rural areas and smaller communities, heavy traffic volumes in urban areas quickly pound down and bond untreated snow into hardpack that is extremely difficult to remove. It takes four to seven truckloads of abrasives to treat the same number of lane miles as a truckload of salt, and abrasives must be reapplied frequently. Sand builds up in catch basins and sewers, necessitating expensive cleanup.

Sand does not provide the snow and ice melting capabilities of salt and liquid calcium chloride. Experimentation is underway in North America and Europe with other de-icers but the chemicals that perform comparably to salt are expensive. One of the most promising, calcium magnesium acetate, costs about 25 times as much as salt. Because of traffic volumes, performance and costs, most cities continue to use salt.

Runoff into rivers and lakes is an environmental hazard. One of the main reasons for implementing the Sensible Salting Policy was to minimize the amount of salt that eventually washes into Lake Michigan. Also, all of the City of Milwaukee's open salt storage sheds were replaced by enclosed storage buildings. Most groundwater contamination is caused by improper storage of materials.

High salt concentrations can hurt vegetation. This is most evident on divided highways with boulevards and medians. Vehicles passing at high speeds spray the salt brine onto the medians and turf damage is visible as a brown strip. On residential streets, the impact of salt is lessened because of lower speeds and reduced salt application rates.

Corrosion of reinforcing steel in bridge decks has been a serious problem but new technology and designs are reducing this problem. Quality concrete is able to withstand some of the effects of corrosion from salt and can reach its expected design life. According to the National Asphalt Pavement Association, salt does not affect "blacktop" pavements. In cold weather climates, vehicle manufacturers recommend regular washing of cars and trucks to remove salt buildup to prevent corrosion.

The Milwaukee County Department of Public Works Highway Maintenance Department is responsible for ice and snow control on the Milwaukee area freeway system. The City of Milwaukee is responsible for maintaining city streets but does not plow or salt the freeways.

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