Salt and sand contribute greatly to lake, river and stream pollution. Once it’s spread on parking lots, streets, sidewalks and driveways, it’s on its way to the nearest surface water and cannot be recovered.

Fifty pounds of salt, or one large bag, can pollute 10,000 gallons of water — which is equivalent to one teaspoon in a 5-gallon bucket of water, which is why municipalities are working to cut salt use while still keeping streets safe.

Dane County UW-Extension representatives have the following tips for salt use this winter:

• Always use a shovel first, especially if the pavement temperature is 32 degrees or more; don’t waste money on deicers.

• Reserve deicers for ice, not snow.

• All salt is not created equal. Various types of deicers perform differently at different temperature ranges. The most common and cheapest is sodium chloride or “rock salt”, but doesn’t work when the pavement is colder than 15 degrees. Magnesium chloride and calcium chloride cost more, but you’ll use less and it works in colder temps.

• Consider getting a pavement thermometer to help determine pavement temperatures, which can vary widely depending on how much sun shines on your driveway.

• Measure your sidewalk and driveway so you know how much you need. A general guideline is to use 1-3 cups of salt per 1,000 square feet. Don’t waste money by using more than is needed.

• Use liquid salt to the pavement before the storm and shovel a little while it’s snowing. After the storm, shovel before using any salt. Often, you won’t need any.

• You can use 30 percent less if you wet your salt with some water before applying it.

• While salt is sometimes mixed with sand to keep the sand from freezing into a solid block, it’s not a good idea to use both at the same time on your sidewalk. The salt will melt the ice, but if it refreezes, the sand can be frozen below the surface where it can’t do any good. Choose one or the other. Try removing the ice by hand first before using either sand or salt.

• If you have an area that tends to ice up, consider making it a priority to remedy next summer so you won’t need to deice in the future.