What does "reduced salt zone" mean?

Question

When you are driving on the highway you always see the "reduced salt zone" signs! What are their purpose, what do they mean?

Answer 1

it means that the section of roadway drains into a municipal water source, or protected ecological area, so they can't put as much salt on the road in the winter. Its a caution to be more aware of potentially slippery conditions in bad weather.