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Science

Freshwater is Getting Saltier, Threatening People and Wildlife (scientificamerican.com) 164

Salts that de-ice roads, parking lots and sidewalks keep people safe in winter. But new research shows they are contributing to a sharp and widely rising problem across the U.S. From a report: At least a third of the rivers and streams in the country have gotten saltier in the past 25 years. And by 2100, more than half of them may contain at least 50 percent more salt than they used to. Increasing salinity will not just affect freshwater plants and animals but human lives as well -- notably, by affecting drinking water. Sujay Kaushal, a biogeochemist at the University of Maryland, College Park, recounts an experience he had when visiting relatives in New Jersey. When getting a drink from the tap, "I saw a white film on the glass." After trying to scrub it off, he found, "it turned out to be a thin layer of salt crusting the glass."

When Kaushal, who studies how salt invades freshwater sources, sampled the local water supply he found not just an elevated level of the sodium chloride, widely used in winter to de-ice outdoor surfaces, but plenty of other salts such as sodium bicarbonate and magnesium chloride. He also found similar concentrations of these chemicals in most rivers along the east coast, including the Potomac, which provides drinking water for Washington, D.C. Where did all of it come from? De-icing salts, Kaushal determined, are part of the problem, slowly corroding our infrastructure.

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Freshwater is Getting Saltier, Threatening People and Wildlife

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  • by Anonymous Coward

    to [current date].

  • Sodium Chloride? (Score:5, Interesting)

    by JBMcB ( 73720 ) on Sunday December 09, 2018 @11:11AM (#57775196)

    People still use sodium chloride as a deicer? Around here, pretty much all municipalities have switched to calcium chloride, which deices better than sodium chloride, and tends to not kill everone's grass. They'll only use sodium chloride in dire emergencies - IE massive ice storm at the end of the season and there's no calcium chloride to be had, which is pretty rare.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      Also, NaCl only works down to about -20 Celsius. CaCl works much better.

      • Also, NaCl only works down to about -20 Celsius. CaCl works much better.

        Also, CaCl doesn't corrode cars and bridges as badly as NaCl does.

        The big advantage of NaCl is that it is cheap.

        Another option is to put nothing on the roads. This is common in southern states, where snowfall is infrequent, and melts quickly. So everyone just stays home when it snows.

        • This is standard in Oregon, and we get lots of ice on the roads.

          Learn how to drive, people. How did they not understand that this was destructive and builds up in their environment and could only ever be a very temporary solution until they learn how to drive?

          What we do after an ice storm is to dump some gravel on the road. It doesn't do anything to our water supply, it just ends up as part of the road shoulder. Yes, you have to drive slower for a week now that there are little rocks on the road. It amazes

          • Your winter only lasts a week?
            • A week is how long the gravel lasts on the road after application. Obviously, considering geography.

              Has it really come to this? Are the new kids anti-intellectual even here now?

              • Anti-intellectual? You came to that conclusion based on your inability to effectively communicate? Show your work.
                • Why do you presume that my ability to communicate hinges on you personally being able to comprehend my statements? Lets just clear that up right now; I write for people capable of comprehension. Even if it is less than 1% of the people whose eyes pass over the page, that is still who I'm targeting.

                  If you didn't comprehend what I said, that gives you no information at all about my success at communicating.

                  There, now you can say you've seen the formula. I doubt it helped you to understand anything, though.

          • That might work in Oregon, but that is decidedly minor league as far as snow goes. I've lived in snowy areas, and if they get behind in aggressive ice control - deicer, plowing both before during and after snowfall things get ugly fast. You'll end up with 3' of ever deepening glacier on all your roads with ruts that will beach the tallest monster truck. That shit will still be there come June.

            Gravel has some nasty side effects. It releases tons of particulates which are terrible for breathing and they clo
            • That's just derpy. We do have snow plows.

              There is absolutely no reason why using gravel instead of ice means you can't also plow.

              You're just waving your hands and making up how you think things would be, instead of looking around and finding out how things actually are in other places.

              • I've lived in places that get serious snow. Multiple feet of it. Biggest storm I ever saw was over 10' in 24 hours. I've seen firsthand what happens, one time in Denver it was subzero for days with storm after storm, multiple feet of snow each time. The plows were running nonstop but kept losing ground. Eventually even major roads were deeply rutted and impassible. Even with best practices sometimes nature can overwhelm your resources. Gravel is not best practice. You might be able to get away with it somew
          • Alaska does not use de-ices either. I think they just pack it down and drive on it until it melts.
      • by Anonymous Coward

        And why the hell would anyone salt the roads at -20C?

        Once it hits -5, it's better to stop. Keeping the road in the state of constant freezing/meting (which is what happens with salting) destroys the surface. Moreover, the slosh on the road when it's -10 or colder means that wipers can't clean what incoming traffic throws at your windshield - at this temperature the washer liquid freezes on the glass with instant loss of visibility.

    • People still use sodium chloride as a deicer? Around here, pretty much all municipalities have switched to calcium chloride, which deices better than sodium chloride, and tends to not kill everone's grass.

      In general it's the chloride that's the problem, not the sodium ion, so CaCl2 is not much better than NaCl for the environment. It does de-ice at a lower temperature, though. https://stormwater.pca.state.m... [state.mn.us] https://www.oxycalciumchloride... [oxycalciumchloride.com]

      • by JBMcB ( 73720 )

        In general it's the chloride that's the problem, not the sodium ion, so CaCl2 is not much better than NaCl for the environment. It does de-ice at a lower temperature, though.

        Er, no. Sodium chloride tends to interfere with water take-up in macro- and micro- organisms. It's an issue with sodium chloride in particular. Calcium Chloride *can* have the same effect, but you need a *very* high concentration. The chloride ions can be a problem, also, but again, you need a TON of the stuff to impact anything.

        It's just one data point, but there is a river that runs near my house that snakes it's way for miles towards a lake. The majority of storm drains in the county I'm in dump into it.

        • by rtb61 ( 674572 )

          Instead of salt, try some lateral thinking. Build your properties above major roads and turn building lots into parks. Safe travel in all weathers and you are directly above transport corridors for easy social and business access, you also recover than land value under roads.

          • Instead of salt, try some lateral thinking. Build your properties above major roads and turn building lots into parks. Safe travel in all weathers and you are directly above transport corridors for easy social and business access, you also recover than land value under roads.

            Good idea, but note that you will now need to illuminate your roads. That takes energy.

    • by jmccue ( 834797 )

      People still use sodium chloride as a deicer?

      No worries, with Climate change this is a short term problem. Maybe only needed for another 50 years or so.

      My motto (or bumper sticker) "Why retire to Florida when Florida is coming here

    • In northern Arizona we use volcanic cinder on roads. The city of Flagstaff owns its own little volcano, which it mines for this purpose.

  • Environmentalism (Score:3, Informative)

    by Anonymous Coward on Sunday December 09, 2018 @11:20AM (#57775232)

    “The demise of water fleas does not just affect the clarity of the water, but will likely also impact the small fish that feed on them,” Hintz adds. “They provide food for the larger fish that humans eat.”

    Conservatives and Republicans, this is why the environment and our ecosystem is important. It's not some "liberal snowflake" luxury. It's about our health and well being.
    And why didn't the summary mention that it's also caused by industrial activities? Business needs to take responsibility for their pollution. Because they just dump or whatever and stick us with the costs.

    • by Highdude702 ( 4456913 ) on Sunday December 09, 2018 @11:46AM (#57775344)

      well we obviously need global warming then to stop the snow so they don't have to use the salt on the roads that is salting up the rivers. plus it will melt some glaciers giving us more fresh water! BRB I got to go start this tire fire, its getting a little cold.

  • by Anonymous Coward

    I remember the same discussion back in the 70s. It also hurts pets and damages roads and cars. In Germany many cities have banned the use of thawing salt on roads and sidewalks; some places still allow it but only in extreme weather. Grit is a perfectly viable alternative and the effect lasts much longer.

  • by slickwillie ( 34689 ) on Sunday December 09, 2018 @11:34AM (#57775296)
    I mean, they should be able to drive on icy roads, right?
    • Physics is physics and friction is friction, regardless what is driving the vehicle. The solution? Don't salt the roads. Put down sand and winter tires or chains should be mandatory. Salting is actually rare in cold-climate countries outside the US as well as cold states in the Western US (i.e. Idaho).
      • by XXongo ( 3986865 )
        I think the original poster was intending to be ironic.

        However, since the problem with driving on ice is mostly that 10% of drivers that don't have a clue of how to drive in slippery conditions, actually self-driving cars would probably help.

        Or maybe not. I think 100% of the software for self driving cars comes from Southern California, where they don't bother programming for unlikely events like ice on the roads.

        • I think 100% of the software for self driving cars comes from Southern California, where they don't bother programming for unlikely events like ice on the roads.

          Or, indeed, unforeseen things like drunk driving, crash barriers and 18 wheelers across the road...

          • All three of your examples though are from non-self-driving cars in situations involving lane-assist features.

            Maybe you're wearing too much cologne and the Musk is clawing at your nose. Or something. Probably Musk-related, though.

      • Electronic traction control is why I can drive around on a sheet of solid ice without chains or traction tires or anything. Even with a dusting of snow on top. Even onramps, offramps.

        Right now self-driving cars suck at snow, but that's about vision. The traction part they'll have an easy time be better at handling than humans.

        • If you're driving on a sheet of "solid ice" and not skidding off of it, you're probably not driving on solid ice. Most cars made after 2012 or so have traction/stability control, and one still sees stuck late-model cars. Physics is physics.
      • by guruevi ( 827432 )

        Most municipalities already use a combination of sand and salt. The problem is more south-wards where ice and snow are much rarer, they tend to spray pure salt the minute a flock of snow hits their pavement. Further north, they don't even use salt until you get a few cm of snow (you just get mud slush).

        Chains aren't a panacea either, you can only go ~30km/h (20mph) on them or risk destroying either the chains or the car and you lose a lot of grip if it hasn't quite snowed that much.

  • by renzema ( 84617 ) on Sunday December 09, 2018 @11:34AM (#57775298)

    "by 2100, more than half of them may contain at least 50 percent more salt than they used to" - a total meaningless statistic. Are are going from 1 ppb to 2 ppb, which is essentially a non-event, or from 1% to 2%, which would have serious implications? Doubling without giving a baseline and what that baseline represents is just scaremongering.

  • This is all hyperbole and other than a few random water tests is very weak on facts. Salinity increases are usually caused by droughts.

  • Who drinks tapwater? Our ruling class doesn't let it touch them unless it's in the shower. Drinking tapwater is a sure class marker of the deplorables, right alongside watching sportsball or murdering animals with assault rifles. Don't believe me? Invite one of their kids over and give zir a glass of tapwater to drink, and see if the parents let zir come over again. Take it from them: don't drink it, don't cook with it, don't even brush your teeth with it. If you can't afford the pittance it costs for pure
    • the poor. You can buy a reverse osmosis filtration system for about $200-$500 bucks per faucet and that should filter out most of the salt.

      Also, when it comes to water rural communities have much, much bigger problems. Their pipes are going on 100 years old and nobody wants to pay to replace them. Estimates put it at $750 billion to fix the whole country. I'm surprised nobody on the left is talking about that. All they talk about is roads and bridges. Get that message across and you could snatch the far
      • All they talk about is roads and bridges.

        Well, yeah, the money spreads farther. Pipes only affect one city at a time. Flint has already been forgotten. Certain conspiracy theories make far better headlines around the country.

  • ...much faster than "climate change". The fact that people are ignoring local pollution to focus on climate change is outrageous. You can't sell carbon credits to "fix" local pollution though.
  • FTFA :-

    .... an experience he had when visiting relatives in New Jersey. When getting a drink from the tap, "I saw a white film on the glass." After trying to scrub it off ....

    He sounds like a model house guest.

  • It's part of the human experience
  • They use a ridiculous amount of salt just to soften water - and dump salt directly into the water reservoir.

    The tech should be restricted or banned since there are other solutions out there.

  • I'd think that seawater infiltrating freshwater sources, as ocean levels rise, would be a bigger long-term threat than de-icing roads.
  • When a person wants to "drive" make them ask their gov for permission.
    Are they a criminal? An illegal migrant?
    Once people who are approved to 'drive" are found then start with much better education.
    Lots of tests and advanced driving simulators.
    Finally normal driving.
    Then bring in advance ice driving as part of testing.
    How a car drives in winter conditions.
    Pass the new tests and a nations driving population will be able to better use winter and summer roads.

    Ensure transport used has the approved

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