How does salt affect our rivers? Eco alternatives for winter ice
By Stacey Malstrom, Water Communications & Outreach Director
Parts of Oregon are celebrating and others are cursing the unusual onslaught of snow across the state this winter. The deeper snow pack could mean more water in our streams for fish and irrigators, but it has also caused major challenges for underprepared cities like Portland, and it has the state testing new deicing strategies – specifically salt.
What’s the big deal about salt?
Salt is used in many parts of the country because it lowers the freezing temperature of water and therefore can help accelerate the melting process of snow and ice. However, after it’s spread on roads or sidewalks, all of that salt has to go somewhere, and most of it washes into the storm sewer and gets deposited into the nearest river. There, it can harm freshwater fish, frogs and other wildlife that aren’t acclimated to salty water, and can reduce water circulation and oxygen levels in lakes and ponds (because salt affects water’s density). At the road level, salt can dehydrate and kill trees and plants growing next to roadways, and there’s some evidence that it could hasten invasion of non-native plant species.
Historically, Oregon has opted for more environmentally friendly and less corrosive options on snow-covered roads, but ODOT announced in December that it would begin using salt more widely in specific problem areas across the state, and last week PBOT tested salt on several roadways.
The debate about salt is sure to continue through the winter months and as climate change brings more frequent severe weather systems, but one area where you can have an immediate impact is at home. Try these river-friendly alternatives to keep your sidewalks and walkways ice-free:
- Pickle brine: Similar to traditional rock salt, brine can melt ice at temperatures as low as -6F°, but it reduces the amount of chloride released into the environment by 14- to 29-percent. Pre-wetting with this substance prevents snow and ice from bonding with pavement, making the ice easier to chip off and remove.
- Alfalfa meal: This natural ice melting option is usually used as a fertilizer, so if used in excess it can add unwanted nutrients into the water system. It’s grainy so it will provide traction and is extremely effective when used in moderation. Look for it at your nearest garden center or pet store.
- Coffee grounds: Save your grounds or ask your local coffee shop for a bag to sprinkle on your icy sidewalks. They’ll provide traction and the darker colors will absorb more heat and help to melt snow and ice.
The best option is simply to shovel your walkways before the snow gets too packed down or turns to ice. If you can’t do it yourself, hire a young neighbor to help – they could probably use something to do while they’re out of school.