Salt & Sand Use in the Winter

Winter is Here! We have gotten a few winter storms now and experienced some icy conditions. With that, out comes the salt and sand on pavement to prevent slips and falls. Salt is tried and true way to melt ice and sand adds traction during the really cold conditions. These are great ways to improve safety on roads, sidewalks, driveways, and parking lots, but they do come at a cost . . . to the environment. Sand adds excess sediment to our waters that can smother habitat for aquatic organisms. Salt is a chemical that is toxic to aquatic life at high concentrations. Salt stays in the water virtually forever and can only be removed by reverse osmosis. While we do not discourage the use of salt and sand, we promote the conservative use as to not be harmful to our waterways.

Friendly reminders on salt and sand use:

• Sand provides traction, does not melt snow and ice
• Mechanical removal snow is the best way to avoid icy build-ups (salt NOT effective with 3 inches of snow accumulation)
• Do not apply salt/sand mix. Use salt and salt separately as necessary, depending on condition
• Salt needs TIME to work (at 15F, one pound of salt needs 60 mins to melt 6 lbs of ice) 
• Apply sand in extreme cold when salt is ineffective.
• Salt (Sodium Chloride) is only effective at or above 15F
• Store salt and sand in a covered container indoors. 
• When applying salt, go for the pattern below:  

*General rule of thumb for salt use: 1 pound of salt fits into a 12 oz coffee mug and is enough to cover 60-70 feet of sidewalk or 20 feet of driveway. You can always add more salt if needed*
For more info, visit https://www.wisaltwise.com/. 
Have a safe and happy winter!

Do you live in a watershed?

Yes! We all live in a watershed. The USGS defines a watershed as an "area of land where all the water that falls in it and drains off of it goes into the same place." 
All the water in the city basically ends up in Lake Superior, but do you know where it goes before then? Do you know the name of the stream nearest you? The rain that falls here at the wastewater treatment plant drain directly to Superior Bay of Lake Superior. If you live more inland, chances are your rain water flows into a storm drain connected to a stream before reaching the lake. Here are a couple of resources to determine the stream nearest you:
Streams of Superior (city website)
Lake Superior Streams (Info on streams from Duluth-Superior area)

We are constantly promoting "only rain down the drain" because storm sewers do NOT go through a treatment process. Do you have a storm drain by your home? Think about all the stuff that snowmelt and rain water flushes from your yard into the drain:

• Road salt
• Dog poop that never got picked up
• Lawn fertilizers and other chemicals
• Grass clippings and fallen leaves
• Dirty washwater from washing your car at home

All of these will find its way to pollute our lake. The map above is a bit hard to read, but all the boxed red text shows our impaired waters due to pollution.

Keeping Lake Superior Blue Is Up To YOU!!

Road salt contaminating our waters

There was a recent article discussing the long-lasting effect of road salt on our water bodies ("Rivers in wintry cities remain salty year-round"). A University of Minnesota study indicates that some lakes can double in salinity in 50 years! Yikes!

Reminder tips on ways to reduce salt and still maintain safe pavements:
1) Clear the area of as much snow and ice as possible. Clearing snow is best done right after snowfall as compacted from walking/driving is very difficult to remove.
2) Pay attention to the products you are using. There are a variety of salts other than sodium chloride (NaCl) such as magnesium chloride (MgCl2). MgCl2 also has the added bonus of not being palatable to deer. There are many other deicing options (cheese brine, anyone?).
3) Pre-wetting salt can immediately begin to lower the melting point of water. Applying liquid salt can also reduce the amount of salt that bounces off and scatters away.
4) Sodium Chloride is not effective at temperatures below 15 degrees F. There wouldn't really be any benefit to salting at extremely low temperatures.
5) Never use more than 4 lbs/1000 square ft
6) Sweep up any excess salt for reuse
7) Do not apply salt with sand. Sand should be used for traction at lower temperatures when salt won't deice.
8) More good info from the MN Pollution Control Agency: here

It only takes 1 teaspoon to pollute 5 gallons of water!

A little bit of this, A little bit of that….

…is what we’ve been working on over here in the Environmental Services Division.  I just wanted to update everyone on what’s been going on so far this year.  Stormwater utility bills were mailed the last week of January, along with the stormwater newsletter (available here).  We had a booth at the Senior Connections/Mariner Mall Health Fair and talked to a lot of people there.  We enjoyed meeting everyone who attended, as well as those staffing the other booths.  We’ll be keeping you posted on events we attend….in March, we have the Housing Expo at Mariner Mall on the 9^th.

Hopefully you’ve heard of the Environmental Matters Webinar Series which kicks off tomorrow with our first webinar presented by Wendy on winter salt (register here).  She’ll be covering salt application, types of salt, and the problems with salt use on the roads.  It’s interesting information that is useful to all of us, especially after all the snow we got yesterday!  We’ll have another webinar on the 28^th, and then two more every month throughout 2013.  All Superior residents who watch the webinars live will have a chance to win a rain barrel in June!  If you can’t watch them live, they will be archived on our website.  Check out the Superior Telegram's article about them here.

Another fun thing that we’re doing right now is working with schools and other groups to set up presentations about stormwater, water pollution, and the water cycle with kids.  We met some smart kids who knew a lot about water at the Boys and Girls Club and had fun doing activities with them.  In March, we’re holding a Water Fair for the fifth graders at two local elementary schools.  We’re also organizing an art contest for fifth and sixth grade students that will conclude just in time for Earth Day in April.

Finally, we’re in the midst of planning a Rain Barrel and Composter Sale with UW Superior.  In the past, the City has made rain barrels available for residents in a pre-order sale.  We’re working on bringing that back this year, and we couldn’t be more excited.  We’ll have more information at our upcoming booths and eventually, on this blog and the website. 

If you have a question or would like a presentation on stormwater or a related topic for a group in Superior, please contact us.  We’d love to work with you!

-Written by Jillian Schubert Edwards

Shaken, Not Poured: The Case for Using Winter Salt Sparingly

Little mounds of salt piled along buildings and sidewalks are a common sight during the winter months in the Great Lakes states.  Now that winter is fully upon us, the plow and salt trucks will be out in full force.  But why do we use salt?  And what is all of that salt doing to the environment?

Salt lowers the freezing point of water.  So, less water can become ice because there is salt in the water. 

What all of this means is that salt can decrease the number of traffic accidents due to slippery road surfaces.  It can also keep sidewalks and driveways clear for pedestrian traffic.  While it’s great that we have an abundant resource that allows us to get around in the winter, it also has some detrimental impacts on the environment and us.  Some impacts of sodium chloride use are:

1.       Damage to vegetation: When salty slush from roads, sidewalks, and driveways gets on your garden or lawn, the salt water can seep into the soil.  Plants can’t get water from the soil as easily, dehydrating them.  The salty water that ends up on leaves, it can desiccate the plant further.

2.       Corrosive to vehicles: Salt is hygroscopic, meaning that it attracts water.  If that slushy spray from passing cars gets on your car, the salt from that slush will attract more moisture to it and will lead to rusting. 

3.       Water pollution: As spring approaches and warmth returns to Wisconsin, the snow begins to melt.  You’ve seen it; rivers of melted snow, pouring into the storm drain.  It takes with it the salt that has been used throughout the winter.  Many storm drains, including the majority of Superior’s, take stormwater and snowmelt (along with anything mixed in to them) into streams, rivers, and lakes.  Lakes are getting saltier because the salt settles at the bottom of the lake and accumulates.  This prevents water from mixing and can be toxic to aquatic life.

What can you do to mitigate some of the detrimental impacts of salt while staying safe in the winter?  First of all (and most importantly), remove as much snow and ice as possible first.  Once it has been walked/driven on and is compacted, it will be more difficult to get rid of.  Second, pay attention to the products you’re using.  Different kinds of salts (besides the most commonly used NaCl) have different temperatures at which they are effective.  Sodium chloride works best at or above 20*F.  For colder situations, use a different product or use sand for traction.  Finally, apply using the guidelines set forth on the package.  Use a shaker to spread more evenly and to avoid spreading on your lawn or garden.  Sweep up excess salt and use it again for the next storm.

Some more links to check out:

City of Superior

Lake Superior Streams

Wisconsin Department of Transportation- Winter Maintenance at a Glance

-Written by Jillian Schubert Edwards

Smart Salting Workshop TOMORROW!

 

-Written by Jillian Schubert Edwards