When it's icy or it snows, officials drop tons of salt and other de-icers on roads in Monmouth and Ocean counties to help make them safer.

But what's the environmental impact of all the salt that's been deployed this winter, which has featured three major snowstorms so far?

Officials aren't sure but recommend limiting use of rock salt and other products.

However, a DEP water quality report released last year said "road salting and improper salt storage are major contributors" to pollution from dissolved solids and "need to be better addressed by the department's water quality management programs."

But salt-contaminated runoff from streets and highways can damage nearby trees and shrubs and affect aquatic ecosystems when it reaches streams and other surface waters, according to the report.

Drinking water in New Jersey has become contaminated by salt in isolated cases, the report said. Road salt also damages road surfaces, bridges, vehicles and electrical fixtures.

David Pringle, campaign director for the New Jersey Environmental Federation, said "the science is very strong that road salt gets into drinking water supplies, so we obviously need to deal with icy roads from a public safety standpoint, but it's also cause for concern."