Author: chogan@directresearch.com

Post #2094: Eighty pounds and no further progress.

 

After losing a total of 80 pounds, at a steady rate of five pounds a month, my weight loss has stopped.

I reached 205 in the middle of January.  I still weigh about that.  I have not yet glimpsed 200 on the scale.

 

Is this because:

A)  In some mysterious and unspecified way I have permanently slowed my metabolism by dieting, and thus am now doomed never to reach “normal” weight of 185 pounds? Do I simply now have a slow metabolism?

B) My body simply wants to be 205 pounds.  (Though, if so, I wish it had spoken up sooner.)  And so, nothing I could ever stand to do will ever get my weight below that “natural” level.  I am now doomed never to reach a “normal” weight of 185 pounds?  Am I simply “naturally fat”?

OR …

C) I’ve been eating too much.

After checking with the oracle, all indications point to C.

Edit 3/5/2025:  Weight loss resumed when I stopped eating too much. I’m now under 200 pounds and on track for a target weight of 185 sometime around the end of May. 

Teaspoons are tablespoons, and other things that suck about dieting.

Above, that’s a 300 calorie peanut butter sandwich.  It consists of a slider roll (about 3″ in diameter) and two tablespoons of peanut butter.  I know the sandwich contains exactly two level tablespoons of peanut butter, because I took the time to measure it.

The peanut butter is the thin brown line barely visible between the two halves of the roll.

I was appalled by this sandwich.  First, by how little peanut butter that was.  But mostly, by how much peanut butter I had been routinely using, of late, when I made one of those freehand, without measuring anything.

And as goes peanut butter, so go most of the portions I’ve been eyeballing.

A common teaspoon, in the silverware drawer, is typically about a tablespoon, in terms of its capacity.  My coffee cup (mug) is more than two “coffee cups” worth of coffee.  My smallest soup bowl, comfortably full, holds about a bowl-and-a-half, as calorie lists typically equate “a bowl of soup” to mean an 8-ounce cup.

I knew all of that, intellectually.  But, somehow, of late, I’d been turning a blind eye to it.

Funny how your mind will play tricks on you.

Particularly if you want it to.

Recalibrating and downshifting

I have committed that most basic sin of long-term weight loss, portion creep.  This is such a common thing that essentially all guides to long-term weight loss tell you to guard against it.  If you don’t routinely measure everything, then once in a while you need to do that, if only to remind yourself of what the portions of food should be, to match the calorie counts you’re using.

To be clear, portion creep doesn’t occur at random.  It has not, for example, inflated the amount of lettuce I eat weekly.  I have not suddenly been faced with a large weekly bill for cabbage or cucumbers.

Instead, the fact that portion creep only occurs for high-calorie, typically high-fat foods, tells me that this is not simply sloppiness.  It’s my brain, working to sabotage me.

And so, for a week or two, I’ll be measuring out “the good stuff”, meaning, energy-dense foods.  Things that are high in fat, mostly, but also starches.  Just enough to remind myself of what the actual portions are, that correspond to the calorie counts I’ve been using.

It’s also worth nothing that the problem items are energy-dense foods that don’t naturally come in fixed quantities.  Of which peanut butter and salad dressing are the poster children.  But also including cheese, meat, and some soups.

In the end, this is just the flip side of the volumetrics approach to dieting.  With volumetrics, you eat lots of items with low calorie density (calories per ounce).  Which boils down to non-starchy vegetables, fruits, and a smattering of other items.

More lettuce.  Less salad dressing.

It’s not rocket science.

Conclusion:  We have met the enemy, and he is us.

Source:  Amazon.

After more than a year, and 80 pounds of weight loss, my diet has ground to a halt.

I’d love to blame my metabolism.  Or my genes.  Bad luck.  Astrological sign.  Tariffs.  Republicans.

Anything but point the finger at myself.

But the fact is, weight loss at this pace is based on just a 500-calorie-per-day energy deficit.  And it doesn’t take much screw that up.  A heavy hand with a few high-calorie foods will do it.

So, maybe this is the end of my weight loss.  Maybe not.  Maybe these excess calories are merely the symptom of my body finally getting tired of losing weight.  Maybe I won’t be able to stand going back to a true 1500 calories a day or so.

There’s only one way to find out.  And that’s to be strict about everything I eat, for a while, and see if the weight loss picks back up.  Or see if I’ve reached the end of my diet.

Post #2093: Explaining Trump trade policy. This one secret changes everything!

 

The Wall Street Journal characterized the Trump tariffs on Canada and Mexico this way:

That’s a bit harsh, isn’t it?

In this post, I’m going to explain what the WSJ and more-or-less all other professional economists are getting wrong about this issue.

This one trick insight changes everything.

The WSJ editorial page may have been a bit blunter than some.  But it’s a fair reflection of informed opinion on this topic.  It’s almost no exaggeration to say that everyone with any professional interest in economics, international trade, or foreign affairs has been baffled by the reasoning behind the Trump tariff proposals.

But maybe, just maybe, these tariffs are not as irrational as they have been made out to be. 

I believe that all the professionals in international trade misunderstand the simple policy logic that drives us inevitably to these tariffs.

I claim that the fundamental error that professional pundits are making is in thinking that these tariff have anything whatsoever to do with U.S. international trade policy.

The inescapable logic of the Trump tariffs.

Viewed as trade policy, these tariffs are every bit as dumb as the WSJ said.  But viewed from a different perspective, they make absolutely perfect sense.  And that’s because these tariffs aren’t Federal trade policy, they are Federal income tax policy.

Huh?

The income tax cuts from the first Trump administration are set to expire.  Depending on who’s doing the estimate, those tax cuts cost the Treasury $300B to $400B a year.  Ish.

To get them extended, without increasing the deficit, you need to find at least $300B a year to make up the loss.

And, to increase the difficulty factor, you’re a Republican, so raising a tax on anything is out of the question.

What’s the easy, no-effort way to achieve that goal of finding $300B a year, without increasing Federal tax revenues?

First, you must adamantly insist that tariffs are not taxes, and that Americans don’t pay for import tariffs.  No matter how stupid everyone who knows anything about anything says that assertion is.  You must insist that tariffs are not taxes, because you, as a modern Republican, are not allowed to raise taxes.

Next, you sort your trade partners, from high to low, in terms of dollar value of imports.  Pick a good round number like 25%.  And go down the list until 25% of the value of imports exceeds $300B.

Even though, again, anyone who knows anything about trade policy will tell you that makes no sense.  I mean, you haven’t even focused on the countries where we have the biggest trade deficit.  You haven’t (say) accounted for strategic materials, or domestic industries that depend on imported parts, or your own vulnerability to retaliatory tariffs.

Instead, you’ve sorted our trading partners by descending order of value of imports (only).

That’s literally as deep as the thinking goes.  Because that’s as deep as it needs to go, to achieve the goal.  Which, recall, is domestic income tax policy, not international trade.  And that’s because the value of imports (less reduction in demand, when the tariffs are imposed) is what determines your revenue.

Now see how far down the list you need to go, before you get your $300B a year.

Answer:  Canada, Mexico, and China.

And suddenly, the entire two-part “policy” snaps into focus.

These tariffs have nothing to do with trade policy, America’s position in the world, or anything else that a reasonable person might consider.

Instead, look at what this policy consists of:

 Part 1:  You must keep insisting that tariffs are not taxes, because you are not allowed to use the t-word, as a Republican.  This part of the policy is required, because the goal is to raise Federal revenues significantly without saying the t-word (taxes).  So everybody has to agree that tariffs are not taxes, and that Americans do not pay their cost.  Even though everybody who knows anything about international trade will tell you that’s incorrect.

Part 2:  Target countries not in terms of our trade deficit with them, or other practical considerations like impact on U.S. industry, but solely in terms of the value of what we import from them.  And that, too, makes sense, because import volume is what determines your tariff revenue, less the reduction in demand that will occur once prices rise in response to the tariff).

Why is it now 25% each for Mexico and Canada, and 10% for China? My guess is, that’s because that’s when they hit the required projection of tariff revenues that they need. Why are we now talking about tariffs on everything, from all countries, characterized now as “reciprocal tariffs”? Best guess, the revenue target has changed, or the estimated revenues from the existing tariffs have changed.

Conclusion

Sometimes it’s difficult for really bright people to understand how not-so-bright people think.  Or for those with expert knowledge to understand the rank amateur.

If the Trump tariffs appear divorced from any rational thinking about international trade, that’s because they are.

But from the Trump administration standpoint, that’s not a bug, that’s a feature.  That doesn’t mean that they were done at random, or that they were otherwise harmless.  Merely that trade policy was not the point.

Instead, import tariffs are simply a) a potentially large source of revenue that b) you can claim is not a tax.  From that perspective, this two-part policy makes perfectly good logic.  If not much sense.

It’s only a bit of a poetic justice that you get to keep your tax cuts largely favoring the wealthy, by substituting tariffs whose burden falls disproportionately on the poor (for the simple reason that the rich have a high rate of savings.) 

Thus, the secret to understanding the logic of the Trump tariffs is that trade policy is just an innocent bystander.   If what you really care about is extending tax cuts, then, eh, if your solution messes up North American manufacturing for the next decade or so, so be it.  

Republicans have agreed to hold hands, close their eyes, and claim that import tariffs are not taxes on Americans.  And ignore how badly this screws up big chunks of U.S. manufacturing, starting with automobiles.

And, ka-ching, there’s the free $300B in revenue you need to extend the existing tax cuts.

Which is what really matters.

Wonky addendum:

Note, by the way, that if this goes through — if those tariffs are counted as revenue, against the Treasury’s losses from the tax cuts, then …

… well, back in the day, when rules still existed in the Federal government, then those tariffs would be permanent.  Or, at least, as permanent as the tax cuts that they funded.

(This, from PAYGO, originally developed around 1990, and, as of 2019, fully in force in both the House and the Senate.  Any legislation passed by the Congress had to be paid for by a combination of tax increases and spending cuts, unless an exception is made, by a supermajority vote.  Here’s a rather complicated explanation from Wikipedia.)

I’m not sure how this would work, under PAYGO, as the tariffs are not based on legislation.  But I would bet that there’s a way for Republicans to claim the money, as they extend the Trump tax cuts.

So, to be clear, this is once again completely unlike normal tariff policy.  If these are put into place, and Republicans (at least mentally) count the revenue against the losses from the tax cuts, then these tariffs must be, for all intents and purposes, permanent.

Luckily (?), there appear to be no rules whatsoever governing the Federal government now.  So we don’t have to worry about these becoming permanent.

Post #2092: Salt rising — through 2/21/2025

 

The final post in this series is:

Post #2100: Measuring road salt in drinking water, a summary.

Original post follows:

In this post, I’m documenting the progress of my road-salt-in-my-drinking-water experiment.

Recall that:

  1. We had a half-inch of rain Friday 1/31/2025 that washed away the piles of road salt that remained from an earlier winter storm.
  2. It should take about a week for water to work its way from the Potomac River to my tap, per Fairfax County.
  3. Nothing filters salt out of the water, so the salt that got washed off the roads should show up in my tap any day now.
  4. After correcting for operator error, my tap water has shown a steady 210 ppm (parts-per-million) TDS (total dissolved solids) for the entire past week.

I am pleased (?) to report that last night’s water sample clocked in at 232 ppm.  And as of 2/8/2025, it had risen to 242 ppm.

Assuming that was not a fluke, I expect that was the beginning of the salt passing through my fresh water system.  The timing is right, in any case.

I’ll be tracking this for another few days, and will continue to document the results, here in this post.

Update 2/21/2025 sample.  The next salt spike appears in the drinking water right on time,following the ~2/13/2025 runoff of the most recent road salting.

 

Between the time of the rain, and now, my tapwater’s TDS increased by about 100 parts per million, against a relatively stable baseline of about 200 ppm baseline. The peak occurred about 10 days after the salt-clearing rainstorm.

But even if that entire increase is, in fact, due to chloride ion from road salt, we still won’t taste it in the drinking water.  The 100 ppm (presumed) chloride ion concentration in the drinking water is well below the threshold (250 ppm) above which (some?  many?) people will detect a “salty” taste to the water.  The bottom line is that, so far, this should not be a generally taste-able water saltiness event.

And that’s a good thing.

In addition, it is far from proven that the uptick in TDS of my tap water is even due to road salt.  E.g., maybe this happens after every significant rain.   But I’m betting that’s the road salt.  And even if it is driven by road salt, there has to be more in the TDS increase that just chloride ions.

It doesn’t matter.  Won’t taste this amount of salt in the water, no matter how you slice it.

In summary, there was a modest increase in my tap water’s TDS.  Timing is about right for this to reflect “salt in the tap water”, from road salt runoff of 1/31/2025.  But nothing has been proven, except that, even worst case, the ion concentration is not nearly enough to give the water a salty taste.

Edit:  As of 2/13/2025, we’re midway or better (?) through the “runoff” step of a new road salt runoff cycle.  Or, if not midway, we’ll get there and beyond today, with a predicted high in the low 50s.)  And so, we should see a smaller, smearier version of this most recent drinking water salt pulse … 2/21/2025.  It’s not clear that this simple rig, or any simple rig, would reliably let you “see” a pulse that small and ill-defined.  (And that’s assuming the measured TDS number for tap water is otherwise pretty steady from day to day.) 

OTOH, it’s no hardship to keep this going.  Just KISS.  All it takes is this cheap TDS meter, a drinking glass, and patience.

Use just one glass.  Test the water twice a day.  But you need to let that cold tap water stand a good long while, if you want a reliable reading out of a slow-read $6 meter.  So, let each sample sit half a day.  Covered.  AM and PM,  you use (and rinse) the meter, dump that water sample, run the tap and replace the water sample, and set it aside, covered. Then leave it alone.  Until it’s time to do all that again.  Repeat twice a day.

It’s idiot-proof.  And sometimes that’s a good thing.

Post 2092: These are a few of my favorite things.

 

These are three things that I try to bring to mind, as I read the news, and the Trump Takeover unfolds.

I take it as given that the reader knows this Presidential transition is not normal.

And that breaking stuff is easy.

In order, my three main points of reality-based comfort are:

The Fed

Source:  Via Wikipedia, “By AgnosticPreachersKid – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=6282818”.

It makes a nice mantra.

I chant that, in my mind, to calm the jumpies that I get, whenever I start thinking about who now has access to what, where, within the computer system that literally makes U.S. Government payments.

Sure, they’ve let the barbarians into the Treasury, and while that opens the door to all kinds of potential mischief and avoidable security issues, I should stay focused on the dollar.  Because everything I own is denominated in those.

So, who makes (creates) the dollar anyway?  And, likewise, who runs the banking system?

The answer I come up with is the Fed. Not Treasury.

At which point I breathe a sigh of relief.  And try to fix that fact firmly in my head.  The (security of) the dollar depends on the Fed, not the Treasury.

At least for now.  I think.

This, despite the Treasury being tasked with creating the physical tokens we exchange as money, in the Bureau of Engraving and Printing.  But a) don’t confuse that with real money, and b) they do that, in effect, under license and control of the Fed, as the bills themselves are Federal Reserve Notes.  It’s why even the lowly $1 bill has a unique serial number on it.

Global warming

The science there is pretty good.  We’ve got a handle on the major trends, under a business-as-usual scenario.  No shortage of credible warnings.

Without a doubt, the pro-fossil-fuel, anti-renewable, climate-change head-in-the-sand posture of the Republican party, at this moment in time, will eventually stand out as having been spectacularly dumb.

Even if I’m an optimist on this — a position that does not come naturally to me — and assume we’ll eventually get a handle on climate change, our descendants will curse us for at least the easily-avoidable costs we now impose.

Better not to burn it.  If you can avoid it.  That’s the minimal answer to fossil fuels.

By that lowest-bar criterion, Republican global warming policy flunks.

Science ain’t going nowhere.  All this anti-science nonsense, in the long run, all of that loses. 

It may take a while.  But it’s not nice to fool Mother Nature.

Medicare?

 

I read where Musk’s Team was going to identify fraud in the Medicare program.

I’ve been around Medicare most of my professional life. FWIW.  So this was a very comfortable topic for me.

And I said, fraud in Medicare?  I’d bet you can find some. 

There always has been, always will be, fraud in Medicare.

Ideally, you’d like to keep it to minimum. As would any insurer.  Or any sane individual, for that matter.

My point being that it’s not as if this issue of fraud has passed unnoticed.

To the contrary.  I can vaguely recall the Medicare program having, effectively, competitions among contractors, to see who could flag the most fraud.  And I vaguely recall that IBM and Watson itself took on this task, at some point.  But without anything much happening.  My memory or not, there’s too much money to be made in stopping it, if nothing else.

Thus, I see a proposal to throw de-identified Medicare claims data up against the latest AI, and … see what sticks?

Not a bad idea. 

I’d be surprised if it hasn’t already been tried. Twice over.  Perhaps Musk has access to a “better” AI?  Perhaps the Medicare claims processors were behind the times?  Or perhaps not. Or maybe it doesn’t matter, or the problem remains ill-suited to AI.

In any case, fraud in Medicare claims.  Been there.  Done that.

I’d bet they’re going to find some.

But no more than anybody else.

But if so, that would be reassuringly normal.  Everybody takes a hack at fraud in Medicare.  To the point where I’m pretty sure there ain’t no low-hanging fruit.  Or not much.

But I recall that Medicare got stung badly, recently, by a novel scam that involved buying up dying DME suppliers, and thereby obtaining the existing DME suppliers’ licensure (registration?) with the Medicare program.   Whoever bought up those dying DME businesses then abused that portfolio of strategically purchased DME suppliers’ credentials.  A lot. Billed the fill-in-the-profanity-here out of them.

Then, last I heard, successfully skedaddled with the cash. 

A notable black eye for Medicare, at the very least. That’s where I lost the thread.  But that’s a novel and well-thought-out scam.  Perhaps that was a one-off.

Separately, when you get right down to it, this Administration knows a thing or two about Medicare fraud.  Here’s a Washington Post article about the several Trump pardons of individuals convicted of serious Medicare fraud (reference).  It’s not often that you get a name to attach to a $1B Medicare fraud scheme.  In the context of “pardoned by the President”.

 

Conclusion

 

This morning, the plants in my yard are weighted down with a quarter-inch of accumulated sleet.  Meanwhile, the sleet has turned to sporadic rain.

I am sitting in front of a lit wood stove, as I write this.  Between the weather, and the way the USA is headed, I needed some fire.

Something basic.  Comforting.  But real.  Something I think I understand.

I want my life to be more along the lines of a stack of kiln-dried firewood.  And a bit less like a dumpster fire.

If that’s not too much to ask.

Post #2091: Blah blah blah blah salt blah blah blah. Part 3: Operator error.

 

Edit 2/7/2025:  One week since a half-inch of rain washed away the remaining salt on the roads … and no sign of salt in the water yet.  TDS (total dissolved solids) readings for properly aged (i.e., room-temperature) water samples are steady at 210 ppm, plus or minus some single digits.

 

Recall that, as of my last post, my road-salt-in-drinking-water experiment was floundering.  My tap water was showing far more variation in measured total dissolved solids (TDS) than seemed reasonable.

Turns out, that’s because a) my tap water is cold, b) temperature strongly affects the conductivity of water, c) this $6 meter measures and adjusts for temperature,

d) extremely slowly.  And e) I’m not exactly a patient person.

I didn’t wait anywhere near long enough for the meter to adjust to my tap water temperature.  And going forward, I’m not going to stand around for a quarter-hour holding this meter in a glass of water, waiting for the temperature adjustment to reach equilibrium.

The solution is simple.  I have to let the glass of tap water sit for a couple of hours, and come up to room temperature.   Then measure TDS.  Once I do that, these “well-aged” water samples all provide consistent readings for parts-per-million total dissolved solids.

Properly measured, my tap water TDS has been around 210-215 ppm TDS for the past three days.  A little higher than the 170 ppm I expected based on “10 grains of hardness” of the water.  But definitely in the ballpark.  And seemingly stable.

Hey, maybe I’m not crazy.  It does, in fact, take about a week for water to pass through the Fairfax County drinking water system.

The presence of a stable, measurable baseline is important for this experiment.

And yet, as I go day after day without an increase in TDS, I begin to wonder whether I just imagined the salty-tasting tap water of winters past.

I expect road salt runoff to produce a big upswing in my tap water TDS, Wednesday-ish of this week, best guess.  That’s based on last Friday’s half-inch of rain washing (almost) all the remaining salt off the roads.  And my vague memory that the salt taste showed up on-order-of a week after road salting.

FWIW, I finally found confirmation that it takes about a week for water to move through my local water distribution network.  When Fairfax flushes the water mains, they change disinfectant chemicals.  Depending on where you are in the system, those chemicals may take up to a week to show up in your tap, and a week to go away (reference).

Depending on your usage patterns and location within the distribution system, it could take up to a week for your drinking water to transition from combined to free chlorine at the beginning of the flushing program, or from free chlorine to combined chlorine at the conclusion of the flushing program.

The upshot is that a) we may still be a few days away from salt showing up in my tap water, and b) while it has taken me a while to figure out how to use my $6 TDS meter, there’s no harm done.

So far, properly measured, the TDS in my tap water has remained steady at around 210-215 ppm.  If a flush of road salt passed through the system, that ought to stand out pretty sharply against that steady background rate.

 

The full story

  • This meter measures water’s electrical conductivity.
  • That conductivity is increased by ions in the water.
  • Such ions are generated when minerals and salts dissolve in water.
  • Thus, the meter can infer the amount of ions in the water, from the water’s conductivity.
  • It then translates that into something the user can understand, such as parts-per-million total dissolved solids (TDS) or salinity.   Depending on the end-use market that is being targeted.

Source:  Mettler Toledo white paper, “Reducing Measurement Error in Conductivity Readings”.  Annotations in red are mine.

 

  • But water temperature strongly affects conductivity.  A 9F decrease in water temperature creates a more-than-10% reduction in water conductivity.
  • Hence, this measurement typically requires temperature correction. The goal is to measure the water’s conductivity, adjusted to some standard water temperature.
  • And this $6 TDS meter includes that temperature correction via a built-in thermometer (and presumably a look-up table on a chip, or something).
  • But the meter is excruciatingly slow about doing that.

I finally got the bright idea of sticking this meter in a glass of ice water and see how long it took to display a temperature of 0 C. 

I gave up, it took so long.  I got tired of holding the meter in the ice water.  I’m guessing it would eventually get there, but it would take five or ten minutes to do so.

In any case, that adjustment is so slow that what I interpreted as the meter reading “setting down” to a final value, in just a few seconds, was nothing of the sort.

And that’s what tripped me up.  With incomplete temperature adjustment, cold water registers as “cleaner” water (lower TDS), owing to the lower conductivity of cold water.

Conclusion:  Never rule out operator error

On the on hand, I could blame the meter for being so slow to adjust to different temperatures.

On the other hand, it’s up to the meter operator to use it correctly.  Or spend the big bucks on one that works faster.

In any case, for $6, I got a very smart meter.  Smart enough to do the temperature correction for me.

But the hardware?  That’s still the best that $6 can buy.  It’s fine, as far as I can tell, but there’s no expectation that $6 bought me some kind of heirloom-quality super-tool.

And, as it turns out, what I got for $6 is a meter that works, but takes forever to settle to a final reading, owing to the glacial pace of adjustment of its internal temperature sensor.

Which I consider fair, for $6.  That it works at all is kind of a miracle.  That was unkind.  What I should have said is “more than fair”.

Now that I know that the temperature correction takes forever to register,  all I need to do is let my tap water samples warm up to room temperature.

And poof, what seemed like a ridiculously inconsistent meter turns out to be … pretty consistent.

Well worth the $6.

I probably need to buy some distilled water, for another buck or two.  Not to test the meter, but to rinse it after I’m done.  By device design and by common acclaim, I get the impression that I’m never supposed to let anything touch the electrodes but water.  Which precludes wiping the electrodes dry, in any fashion.  But, I think that if I just let the little electrodes air-dry, after tap water, I risk “poisoning” the electrode surfaces over time with calcium carbonate deposits, a.k.a., water spots. This, by analogy to premature dulling of un-dried razor blades by the thickness of water spots (Post #1699).

Distilled water, by contrast, leaves nothing behind when it evaporates.  So you don’t dry them, you rinse them with pure water and then allow them to air-dry.

Otherwise, the experiment is now on track.  I have documented a stable baseline of around 215-225 ppm dissolved solids in my (room-temperature) tap water.

I just need to give it a few days for the road salt to work its way from the Potomac River to my water faucet.

Post #2090: Documenting the post-snowmelt salt spike in my drinking water. Part 2, not obviously a fool’s errand.

 

In this post, I do a back-of-the-envelope calculation on salt in my drinking water.

Is the road-salt-driven spike, in salt in my drinking water, likely to be big enough that I can detect it with a cheap total-dissolved-solids (TDS) meter?

If not, this is a fool’s errand.

Spoiler:  Yes, the increase in ions (here, part of total dissolved solids), from this hypothetical “salt spike” in the drinking water, as a result of the road salt washing off the roads, should be more than big enough to be detected using just a cheap TDS meter.

All I really need to do is stick that meter into a freshly drawn glass of water, once a day.  And record the results.  No muss, no fuss, almost no effort.

If there’s no “spike” in ions — interpreted by the meter as a sharp rise in TDS — then that’s that.  No matter what I thought I tasted in the water.

As a bonus, I get to use grains of water hardness in a calculation involving metric units.

Chapter 1:  Wherein Sodium and Chlorine, who had been bound together as Rock Salt for hundreds of millions of years, are now Released, and Go Their Separate Ways.

One of the stranger twists in this whole road-salt-life-cycle saga is that the sodium and chlorine ions from the road salt now permanently part ways.  Or, at least, in the typical case, do so.

This is usually expressed as “the sodium does not travel as far”.  In hindsight, I think this means that if you filter the salt water through dirt, the sodium ions will preferentially stick to the dirt. I vaguely sense that “ion exchange” is at work here.

This tendency for the sodium to “stay put” is also why the sodium is fingered as the cause of the localized damage to vegetation.  Apparently, that’s why rock salt (NaCl) “burns” lawn at the edge of salted sidewalk, but not so (or as much) calcium chloride (CaCl2).

For all intents and purposes, magic happens. What begins as simple salt water ends up passing along just the chloride ion, out of the salt (NaCl).

Presumably, that chloride ion is now dragging along god-knows-what ion-of-the-street with it.  Something it picked up in the dirt, no doubt.  Calcium, maybe, from the soil it passed through.  Apparently, it doesn’t matter, or something, because I can’t find a ready discussion of what takes sodium’s place.

In any case, so the story goes, what starts off as salt does not end up as simple dilute salt water.  Stuff happens along the way.  I suspect that contact with the dirt plays a major role in that.

So Chloride ion travels, but Sodium ion stays at home.  Or so they say. 

Except sometimes?  Flashy urban environment.

I noted that much of the research on road salt in the water was done in New Hampshire where a) they apparently use a lot of road salt, and b) the issue is contaminating water wells.  So that research is clearly talking about well water, which is most assuredly water that has percolated extensively through soil.  (Although, in fairness, they also manage to salt up quite a few lakes and streams.)

Here in NoVa, by contrast, I think we’re at the opposite end of the percolation spectrum.  Around here, it’s road runoff to culvert to storm sewer, to clay-banked “flashy” urban stream.  To the Potomac.  In my mind, I’m not seeing a lot of filtration of any sort take place.  As a result, I’d bet that what starts out as salt water mostly ends up salt water, sodium intact, in the Potomac.

But I don’t really know.

All I know is that, as with many divorces, the tale you’ll be told about the breakup of Sodium ion and Chloride ion can’t possibly be the full story.  Ions have charge, and charge must balance.  So that the only way chloride can drop its ex — the sodium ion — is to pick up a suitable replacement.  I can only guess that, somehow, whatever that replacement ion is just doesn’t much matter. So nobody talks about it.

They dump on the ex (sodium) for killing the vegetation at the site of application.  But nobody bothers to name Chloride’s current partner.

Either that, or I fundamentally misunderstand something about this.

 

Grains of hardness should set my TDS baseline.

Horsepower.  Tons of cooling. British thermal units.  Teaspoons.

Grains of water hardness.

There’s just something about crazy old units of measurement that simply refuse to die.

At any rate, here’s where this stands.

I’ve ordered a cheap TDS (total-dissolved-solids) meter.  Assuming it works, it’ll give me good information on the density of ions on my drinking water.  Expressed in parts-per-million (ppm).

I’m going to draw daily samples of water for the next N days (like, 14 or boredom, whichever comes first).  By samples, I mean fill a mason jar with water and give it a labeled plastic top.  Kitchen faucet (so I know it’s well-used every day).

Plus, no at-home science project is really complete if it doesn’t use a mason jar.

Then I’m going to do the obvious things.  Test the water, using the meter.  And, with the aid of my wife, taste the water, blinded as to which mason jar is which.  Hoping that “ion count is up” and “tastes like salt” days a) exist, and b) coincide.

This, assuming that TDS is normally slow-varying, and doesn’t just like spike at random times all year long.  (Or, for that matter, does not spike following rainfall, regardless of salt on the pavement, something I would in theory need to test for.  These are things that I hope are true — basically, that my water’s TDS does not normally have short-term intense spikes of ions.  But this is something that I hope is true, not something that I know or have shown to be true.

But how big a blip can I reasonably expect?  Will I even be able to register it, with this cheap meter? 

That’s what this post is about.

The commonly-stated standard for drinking water taste is that water should not exceed 250 ppm (parts per million) chloride ions.   At least, this seems to be what Google’s AI tells me, expressed as 250 milligrams chloride per liter of water.   Above this level, a salty taste is evident.  (To some, I guess.  Salt sensitivity varies across individuals and over time, but 250 ppm is what gets cited as a common standard for avoiding salt taste in the drinking water.)

So if I can taste the salt in my water, that ought to correspond to that level of chloride, or higher, in the water.

That’s going to add to the total dissolved solids that are routinely in my water, that is, my “baseline” TDS.  Which my town’s legally-mandated annual water quality report helpfully lists as being in the range of 5 to 10 grains of hardness.  By weight, I believe that’s almost entirely calcium carbonate.

And 10 grains of hardness works out to be 640 mg of dissolved minerals (mostly harmless calcium carbonate) per gallon of water.

(So “a grain” is weight, now equal to about 64 milligrams.  The answer above is what you’ll get from Google’s AI.  And a grain of water hardness is a grain of dissolved minerals, per gallon of water.)

The term grain comes from exactly where you’d think.  Its supposed to be the weight of an idealized grain of wheat.  Or so they say.  But it is widely listed as equaling 1/7000th of a common (avoirdupois) pound, and so it doesn’t play nicely with standard U.S. units.  Aside from the fact that a grain is tiny, I think this explains why grains are not used in the U.S. (outside of ammunition and water hardness, and I guess alchemical receipts.  But never in the day-to-day.

To put those two numbers on common footing, note that a gallon is four liters.  So ten grains of water hardness is (640 mg/4 liters =~) 160 ppm dissolved solids.

Or close enough.  (When I ask Google, it helpfully tells me that a grain of hardness works out to be 17.1 ppm, or ten grains of hardness is just over 170 ppm.  Plenty close enough to the prior estimate, for this work.

And, because, by weight, calcium carbonate makes up the vast majority of what’s dissolved in my drinking water, that should be my baseline TDS reading.

Which means that the expected minimum taste-able chloride spike (250 ppm) should easily show up on top of my background TDS of around 170 ppm (10 grains of hardness).

Things could still go wrong.  Perhaps the day-to-day TDS level of my drinking water is erratic, spiking up and down all the time.  Perhaps it kicks up after every significant rainstorm (so that the expected coming spike might have nothing to do with salt.)  Perhaps this $6 meter is so unreliable that random meter errors will swamp the expected salt-driven increase in TDS.

But if none of that is true, then if I can taste the salt in the water, the concomitant jump in ion concentration in the drinking water should easily register on a cheap TDS meter.

Conclusion

So far, this is not a fool’s errand.

A cheap TDS meter should be good enough to document the expected salt spike in my drinking water.

Addendum:  Initial impression of cheap TDS meter.

My $6 TDS meter arrived.  Worked right out of the box.  At any point in time, it seems to give a consistent reading.

But glasses of water drawn three hours apart differed almost 10% in their measured TDS.  I don’t know whether that’s the native uncertainty of the meter, poor water-draw technique on my part, or actual hour-to-hour variation in my tap water’s TDS.

After a little poking about, I find a few things.

First, weirdly enough, there are different procedures for drawing water to test the water, as opposed to drawing water to test the plumbing.  If you’re testing the (incoming) water, common advice is to let the tap run full-on for five minutes, then take a sample.  By contrast, if you’re (e.g.) testing for lead in the pipes, apparently, you want to catch and test what’s sitting in the pipe, and you don’t want to flush the pipe at all.

I’m only letting the kitchen tap run 30 seconds.  (But, honestly, if the difference across readings is due to stuff coming out of my pipes, I’d kind of like to know that.)  I may try some five-minute flushes to see if that gives me more consistent readings.

In any event, change of plan.  I’m just going to measure the TDS of my kitchen tap water several times a day, over the next couple of weeks, and record the results.

With luck, my $6 meter will last the full two weeks.

Post #2089: Documenting the post-snowmelt salt spike in my drinking water. Part 1.

 

Major snowstorms in my area (Northern Virginia) are often followed by salty-tasting tap water, some days later.  Salt that was spread on the roads gets dissolved by the melting snow (or rain), runs off into the creeks, down to the Potomac, and from there, into our drinking water.

This is a well-known phenomenon across the northern U.S.

Here in Northern Virginia, sodium and chloride levels in the drinking water have been rising for decades, as documented by the Washington Suburban Sanitary Commission:

Source:  WSSC.

As the WSSC states:

The levels peak in the winter months and are higher in years where we experience more winter weather events. Because there is no economically feasible way to remove salt during filtration, higher levels end up in the drinking water.

Those annual averages are interesting, but here I want to document the short-term increase in salt in the drinking water following a big snowstorm.  Right now, all I have to back up my claim that road salt makes the water taste salty is a) my taste buds, and b) my recollection of salty-tap-water events of the past.

So this time, I’m going to try to capture that post-snow-melt salt spike in my tap water, in hard data. 

Measure it.  Day-by-day.  As it flushes through the system.

Cheap water quality testers are all water conductivity testers.

If you look on (say) Amazon, you can buy cheap little meters to measure total dissolved solids (TDS) in water.  As above.  These are often included with high-end countertop water filters, so you can see that something has been removed from the water, in passing it through the filter.  (My understanding is that consumers use the TDS reduction as a marker for when to change the water filter cartridge.)

You can also buy remarkably similar-looking meters to measure water salinity.  These are often targeted toward (e.g.) aquarium owners, and pool owners, either of whom may need to keep water salinity within a defined range.

You can even buy meters labeled for measuring the electrical conductivity of water.  Need I say that those cheap water-conductivity meters look almost identical to the first two?

Turns out, those are all the same meter.  They all measure the electrical conductivity of water.  They just label the resulting output on different scales.

Maybe — I haven’t quite figured this out one way or the other — there may be non-linear adjustments linked to the named use (salinity, TDS).  Maybe not.  I don’t think my $5 is going to buy me a lot of sophistication.  But these days, you never know.

Starting off with a DIY flop

 

So, assuming I have deciphered the technical stuff right (below), to capture the salt spike, all I need to do is measure the electrical resistance of my water.  Day after day, in a repeatable fashion.  For, I’m guessing, a couple of weeks max.

The salt, passing through the system, should show up as a temporary spike in the conductivity of the water.

To be clear, I don’t think I’m looking for some little hiccup in the data.  Back-of-the-envelope, I’m hoping for roughly a doubling of the conductivity for the days in which the salt spike passes through.  Which I have already predicted will be this coming Wednesday, based on my hazy recollection of the past.

I’ve got an ohm meter.  Somewhere.  It can measure resistance (ohms).  How hard could it be, to rig up some way to use my VOM (volt-ohm meter) to track the resistance (the mathematical inverse of conductivity) of my tap water.

Long story short, this DIY water-conductivity meter failed.  I was unable to make a reliable measurement.  After assembling the hardware (two bolts, stuck to a plastic lid, in a mason jar of water, connected to a VOM), the estimated electrical resistance of the water wandered all over the place.  Substituting stainless bolts for the galvanized bolts shown above did nothing to correct the problem.  I think that, perhaps, my VOM was just not up to the task.

After giving it a couple of tries with this DIY approach, I gave up and ordered the $6 meter pictured above.

I still don’t really know why my DIY water-resistance meter didn’t work.   Might have been as simple as a bad battery in the meter.  Not worth pursuing, when I can buy a meter for $6.

It really is this simple?  The theory.

Pure (distilled) water is a poor conductor of electricity.

But if you add ions to the water — from dissolved salt (Na+Cl-) or calcium carbonate (Ca++ C03–) or baking soda (Na+ HC03-) or hydrochloric acid (H+ Cl-) or whatnot — the ions act as charge carriers, and so allow electricity to flow more easily in the water.

The more ions you add, the better the water conducts electricity. (Within reason or at modest dilution.)   All the ions in the water contribute to the increased conductivity of the water.  Those could be “dissolved solids” ions, as from calcium carbonate in hard water.  Those could be “salt” ions, as in, the salt in a salt water aquarium.

In fact, all of these super-cheap TDS/salinity/conductivity meters measure the conductivity of the water.  Period.  They just put a different label, and perhaps a different scale, on that measured conductivity.

The first thing to note is that these meters can’t distinguish salt from other ions.  All they do is tell how conductive the water is.  That depends on the concentration of current-carrying ions in the water.  All ions of all types contribute to that.

The bottom line is that, strictly speaking, my $6 salt meter does not measure salt in the water.  It measures the total ion concentration in the water, of which salt contributes a part.  It does that by measuring the conductivity of the water.  And then it displays the result in units that match salt-concentration units (like ppm NaCl and such).  (I am also pretty sure it makes a temperature correction as well, as water conductivity varies with temperature, and the standard for reporting is conductivity of water at 25C.)

But, while these meters react to all ions in the water, they are blind to dissolved non-ionic compounds.  Like, sugar, say.  Sugar molecules remain intact (and carry no charge) when dissolved in water.  Dissolved sugar does not materially affect the conductivity of water, and so a cheap “TDS” meter will not respond to dissolved sugar or other dissolved non-ionic organic matter in the water.

The upshot is that the thing that’s sold as a “TDS” meter … isn’t.  Not if “total” includes things like sugar — dissolved organic material that is not ionic in nature.  It’s blind to that stuff, because that stuff doesn’t affect the conductivity of the water.

But that’s only fair, because the “salinity meter” version of it doesn’t measure salinity, either.  For example, I’m pretty sure that adding vinegar to the water will cause the conductivity to increase. On a meter labeled as a “salinity tester”, that increased conductivity would be labeled as increased saltiness.

As far as I can tell — and certainly at this price-point — the only way to measure the different ions separately is through chemistry.  Old school, you add reagents to react with certain ions, precipitate them out of the water.  You then filter out, dry, and weigh the precipitate to infer the quantity of the selected ion in the batch of water.  (Or you buy a meter with exotic-material electrodes that react chemically with certain ions and not other.)  Either way, that level of effort and expense is way beyond what I contemplate here.

Separately, and well known, the fact that these meters react the same to all dissolved ions means that “TDS” isn’t a good measure of drinking water cleanliness.  For most drinking water, TDS is simply measuring the total dissolved mineral content.  For me, here in the Town of Vienna VA, almost all the dissolved solids are from a water hardness of around 5 to 10 grains (per our mandated water quality report.)  This is almost entirely from harmless calcium carbonate, dissolved in the water.  The relatively high TDS in this case doesn’t mean that my tap water is bad, just that it has dissolved minerals in it.

Conclusion

I hope this has been clarificatory.

There is only one underlying type of cheap water quality meter.

Cheap (sub $10 on Amazon) TDS meters, salinity meters, and water conductivity meters all measure the electrical conductivity of water.  Water conductivity is driven by the concentration of ions present in the water.  All ions are lumped together by this measurement.  And these meters are blind to dissolved non-ionic material, because (e.g.) stuff like sugar doesn’t materially affect water conductivity.

So, really, at least at this price point, there are no salinity meters or TDS meters.  There are only water conductivity meters, and the labels placed on them.

The situation isn’t as dumb as I’ve painted it.  If you know what’s going into your water — say you are trying to adjust the salt level in a swimming pool — then yeah, that meter will function for you as a salt meter.  Because you know that it’s your salt that’s increasing the ion count and pushing up the conductivity of the water.

Similarly, if dissolved organic non-ionic compounds are not an issue for you  — no sugar in your water, that you know of — then the same meter may well serve as a useful TDS meter.  For drinking water — where dissolved organic matter is assumed to be minimal — these simple conductivity meters work well as total-dissolved-solids meters.  In other contexts — such as sampling raw water from a lake or stream — that would not be true.

For the moment, all I need to do is take a water sample a day, from my kitchen faucet.  Just a mason jar, rinsed and filled.  Store that away.

And then, if the story is as I think it is, in a couple of weeks, I should be able to go back through the samples and identify the “salty” days through blind taste-test.  And, if all goes well, my $6 TDS meter will highlight the same days as high TDS days.

If it all goes to plan, I’ll have documented the post-snowstorm salt spike in our drinking water by both blind taste test, and by measured dissolved solids.

Post #2088: Why are there always little piles of salt left in the road?

 

It’s going to rain all day today.  The forecast is for half an inch or more.

Today, therefore, I must appreciate the little piles of salt that are left in the roadway.

Because tomorrow, they shall all be gone.

They will have begun their journey to return to Mother Ocean.  Whence they originated, back when dinosaurs roamed the earth.

Think of it as a salty circle-of-life kind of thing.

Observation:  There is (always!) excess salt left on the roadway.

We have reached the ugly end stage of this last snowstorm.  Patches of white snow remain, but only here and there, on lawns and roofs.  Parking lots remain clogged with great dirty piles of snow.

And roadways are littered with ugly little piles of salt.  As they always are, after a snowstorm in this area.

Call those ubiquitous little piles of left-over road salt the “excess salt”.  (Which is kind of judgemental, but for now, I just need something to call them).

I’m not talking about private parking lots, or walkways, or whatnot.  Places where the property owner spreads salt in some catch-as-catch-can manner.  I’m just talking about little piles of leftover salt, on the public roadways.

If you think about them, at all, it’s not as if VDOT set out to leave a bunch of salt lying around, when they salted the roads last week.

For one thing, those piles of excess salt are a deadweight loss.  It takes money to buy and spread that salt.  But the left-overs didn’t do anything useful.  They just add to the subsequent salt burden on local rivers and, in my case, the water supply.

In fact, it’s fair to say that every state DOT is aiming to use less salt.  Not just for the environmental impact, but because it rusts out cars, bridges, rebar embedded in concrete, and so on.

Paradoxically, part of this push to reduce the use of road salt is the now-common practice of “brining” the roads ahead of a snowfall.  That is, spraying everything with salt water, which then evaporates to leave a microscopically thin, uniform layer of salt.  This is used for anti-icing (to prevent snow from sticking to the road), as opposed to traditional de-icing (un-sticking already-frozen snow).  That preventive approach to disbondment (see prior post) results in less salt being used, in total.  In Virginia, brining the roads only came into general use in the 21st century, and was relatively uncommon as late as the mid-1990s (reference, .pdf). 

Finally, as far as I have been able to tell, VDOT (and similar) aim for a uniform application of salt, just sufficient to achieve “debondment” between ice/snow and pavement.

And yet, little piles of salt in the “corners” of the roadway remain a fixture of the urban winter landscape.  Post-snowstorm, we always end up with deposits of rock salt in the dead space next to the curb, sometimes between the lanes, and in general, on the road surface wherever tires do not routinely roll.

So that’s a little bit of a puzzle, isn’t it.  Everybody involved is trying their damnedest to use as little road salt as possible.  The salt is applied by professionals using the best known techniques.  They aim for a uniform application of salt sufficient for debondment.  But we still end up with little piles of excess salt everywhere.

 

Why?  Mere carelessness is not an adequate explanation.

Why is there always excess salt, in little drifted piles, on the road, after a snowstorm?

This is a surprisingly hard question to answer.  Around here, the excess salt piles show up at intersections.  There’s no obvious explanation for that.

My best guess is that this occurs because a) the pavement of an intersection gets double-salted (one salt-truck pass for the main street, one for the side street), and b), as a matter of geometry, larger intersections effectively result in higher piles of excess salt at the curb.

Other explanations do not seem to hold water.

Mere sloppiness?  No. 

Naively, you might think that we see these excess salt piles because VDOT went at it with too heavy a hand.  Or spilled some extra in those spots.  You can try to dismiss it as the result of mere sloppiness.

But attributing those ubiquitous piles of excess salt to “good enough for government” work does not stand up to scrutiny.  For one thing, even a bit of research shows you how seriously VDOT (et al.) take the the timing and calibration of their salt spreading and spread rates.  It’s as close to a science as they can make it.  For another, those little excess salt piles show up everywhere, pretty much, regardless of which government entity or contractor put the salt down on the public road.   No matter which year.  And they have done so, ever since I can remember.

Nor does the excess salt pile up everywhere, as it would if VDOT simply applied it with too heavy a hand.  Around here, I see those excess salt piles at intersections, on highway overpasses, and where lanes merge.  I specifically see none — no visible salt crystals whatsoever — along sections of road between intersections.

But what would be the systematic reason for them?

So, to the contrary, I’m going to start from the notion that there’s probably a reason that we always end up with little piles of left-over road salt.  A reason those show up in the intersections.  And I’m betting it’s something inherent about salting the roads that leads to this.

In other words, I’m betting that we always end up with little piles of excess salt because that’s an inherent and unavoidable part of salting the roads.

I can’t prove that, but here are my best guesses as to why we only see those excess salt piles in certain locations.

Guess 1:  All VDOTs, everywhere, put extra salt down at intersections?  And always have.  Presumably on purpose, as a safety measure?  To roughly the same level of excess.  So, in effect, the excess salt was put there, on purpose by VDOT.

If so, they have all, collectively, been pretty quiet about doing that.  I have found exactly zero evidence to suggest this is true.  No directions to do so, no mention of doing that in a “best practices” manual, and so on.

(There may be some governments that only salt intersections, but VDOT is not one of them.  Nor is the Town of Vienna.  Near as I can tell, every street in Vienna got salted.)

In addition, most truck-mounted salt spreaders aren’t set up for a lot of fine-tuning on the fly.  Like, turning them up, as you cross an intersection.  For the simplest salt-spreader rigs, the only in-cab control is an on-off toggle switch (top, below).  More modern ones let you control the flow of salt, on the fly (bottom, below).  Neither style looks like it’s set up to encourage the truck driver to fiddle with it, while driving a piece of heavy equipment.  Say, at night, in a driving snow, with traffic.

Source:  A couple of installation manuals for truck-mounted salt spreaders.

So, while it’s not out of the question that VDOTs around the country somehow turn up the salt flow at intersections, this seems unlikely.  I can find no mention of this as a standard practice, and it runs contrary to the fundamental notion that salt, for road use, is for disbondment of ice/snow on pavement.

Plus there’s no obvious way to do it, other than asking the salt truck drivers to slow down at every intersection.

Guess 2:  The pavement of the intersection gets double-salted (once for salting the street, once for salting the cross-street).

That’s a fact.  If you’ve set the salt spreader to provide X salt per 1000 square feet of road, then road intersections get 2X.  Once for the main street, and again for the cross street.  And, really, you might end up laying down extra salt anywhere salt trucks have to make multiple passes to completely salt a stretch of pavement (e.g., where there are an odd number of lanes, or where lanes begin or end, or merge areas.)

Guess 2A:  Large intersections should generate more noticeable piles of salt  at the curb line (compared to small intersections). 

That’s also more-or-less a fact, owing to geometry.  The area of an intersection increases with the square of the number of lanes.  Salt is spread over the entire area.  But the length of curb line is … roughly constant, at least until you get to the point where there’s a divider between the lanes.  The upshot is that an intersection between six-lane roads ought to give curb-side excess salt piles that are nine times higher than you’d find at the intersection of a pair of two-lane roads.

Guess 3:  Salt is applied uniformly on the roadway, but somehow migrates to the intersections?  I don’t think this is true, but I can’t prove it.

For sure, salt migrates short distances on the roadways.  It moves out of the path of actual tire contact, which is why the excess salt piles are always in the “dead” spots in or around the roadway.  But that would account for salt moving a few feet, not hundreds or thousands of feet down a typical suburban street or arterial roadway.  Which is the only way this hypothesis would explain salt at the intersections.

In addition, VDOT puts a lot of thought into keeping the salt where they put it.  It is common practice to pre-wet the salt, both so that it stick better, and so that it starts melting snow faster.  In addition, best practices call for applying road salt only after some snow has fallen, specifically so that the salt will stay put.

Finally, I think the contrast of intersections and surrounding roadways is too pronounced to have been produced by such a sloppy process as salt being pushed around by tires.  With this last snowfall, I see no salt crystals at all on the road, until I’m literally at the intersection.

Upshot:  Of the three mechanisms that would generate salt piles at intersections (only), and particularly at large intersections, I think it’s due to the inherent double-salting of the intersection pavement, coupled with simple geometry that results in higher excess salt piles at larger intersections.

Drinking water contamination, or, why do I even care about road salt?

I care because I’ll be tasting salt in my tap water sometime next week.  Based on past experience, I’d bet that’ll start around Wednesday or so.  That, as a result of the road salt being washed into the Potomac River by today’s rains.

There are enough reports of road salt contaminating drinking water that I’m pretty sure I’m not fooling myself about the salty taste of the water.  This, even though my wife can’t taste the salt.  Sensitivity to the taste of salt varies substantially across individuals.  And, for an individual, it varies considerably with the amount of salt in the diet.  (Unsurprisingly, the more salt-deprived you are, the more sensitive you are to the taste of salt).

Of more scientific interest, the fact that I can taste the snow-melt salt in my drinking water suggests that post-snowfall salt (chloride ion) content of my drinking water routinely exceeds 250 parts-per-million, the lowest threshold at which some people can taste the salt.  At least a quarter-teaspoon of salt, per gallon.  Not a health hazard for most, but enough that I can taste it.

But is that plausible?  Do we really put down enough road salt to make the drinking water salty?

Yep.  A simple and conservative back-of-the-envelope calculation says that if the Town of Vienna, VA applies road salt a standard rate, it would plausibly generate a brine salty enough to taste, as that salt mixes with half-an-inch of rain.

Further research shows that in a big snowfall, Vienna applies orders of magnitude more salt.  The Town newsletter reported 600 tons of salt used for a January 2016 snowstorm that dropped about 30 inches of snow (Vienna Voice, March 2016, page 6).  Or roughly 60 times as much salt as was assumed for the calculation above.

The upshot is that yes, a single application of road salt, at a middle-of-the-road rate, followed by half-an-inch of rain, should result in runoff from the Town of Vienna that has a noticeably salty taste.  And that exceeds current EPA water-quality standards for salt in the water.

I may or may not be able to taste the salt, with this modest snowfall.  After all, that will depend on the rate of salt use across the entire Potomac watershed.

I may yet invest $20 in a cheap salt meter, and track the chloride ion content of the water.  Just to see if that’s accurate enough to document the wave of road salt that will be passing through my local water supply next week.

Conclusion?

This is a bit of an odd post, even for me.

You’ve probably seen little piles of excess salt on the roadway all of your life.  And yet, each time, if you thought about them at all, you probably just tut-tutted them away.  Dismissed them with some sort of ad-hoc explanation.  Maybe your local DOT (or alternative) is just sloppy, or something, and over-applies the salt.  Or maybe cars effectively sweep the salt along, until it gets to the intersections, where it stops.  Or maybe VDOT specifically and purposefully over-salts intersections.

I don’t think any of those simple explanations is correct. They do not explain the consistency and ubiquity of these little piles of excess salt.  No matter the year, or the jurisdiction, if they salt the roads, little piles of excess salt are a normal and expected part of the urban winter landscape.

My best guess is that the ubiquitous piles of excess salt are an inherent and inadvertent part of salting the roads in winter.  The most plausible explanation of why the excess road salt is consistently where it is, around here, is a straightforward double-salting of the intersections.  If you are salting the pavement adequately in all directions, then you are salting the pavement of each road intersection twice adequately.

And for larger intersections, that over-salting-rate gets amplified, as the salt strewn over the collection area of the intersection (which rises with the square of number of road lanes) gets squeezed against more-or-less the same length of curb.  So that an intersection with twice the lanes should yield four times the concentration of excess salt pushed to the curb.

But in the end, it comes down to whether or not there’s anything actionable.  Is there any way to avoid those piles of excess salt?  And would it make any material difference, if you did?

And there, I think the answer is no.  No, you can’t avoid over-salting intersections, with manually-controlled salt spreaders.  For most, the driver simply turns the salt spreader on when the truck is moving, and off when the truck is stopped.  (Having salt spreaders that are synced to vehicle speed is considered a big step up from the standard setup.)

When you get down to it, the problem is the use of road salt.  Full stop.  Modest over-use on intersections adds trivially to that problem, for the simple reason that intersection area is a small fraction of total road area.  So the problem of excess salt in the intersections is not worth addressing, particularly if that would require use of more sophisticated (e.g., GPS-run) salt spreader controls, to avoid dumping salt twice on the same intersection.

My guess is that as long as we salt the roads, we’re going to see little piles of excess salt in the road intersections.  I think that’s an inherent and unavoidable part of the process.  But that, empirically, that additional salt in the intersections is a drop in the bucket, compared to the total amount of salt spread on the roads.

End of story.

The only followup will be to try to document the spike in salt in my drinking water, as a consequence of the runoff from this most recent storm.  And that will depend on whether or not I feel like shipping $20 off to China, via an American oligarch, by the purchase of a cheap salt tester on Amazon.

Post #2087: Vienna pool, vote deferred until at least August 25, 2025.

 

I got a hot tip from some email correspondence that the scheduled 1/27/2025 vote to raise the meals tax … would be deferred.

That turned out to be a true rumor.  Took TC all of four minutes to raise, discuss, and vote to defer.

About half of the four minutes consists of a single long comment by Council Member Brill, regarding the uncertain outlook for the Federal workforce.  This was met with a smattering of applause, which the Mayor then immediately quashed, per TC SOP.

Here’s the four minutes of audio, starting just a few seconds before this item came up:

I gave that four minutes of audio to the AI lurking within notebooklm.google.com, to summarize.  Here’s how the AI summarized it, primarily based on a lengthy comment by Council Member Brill:

AI summary from notebooklm.google.com

1 source

A town council meeting transcript reveals a discussion regarding a proposed 10-year increase in the meals tax from 3% to 4%. A council member motions to defer the decision until August 25th, 2025, citing uncertainty surrounding potential federal telework policy changes that could impact local residents’ employment and, consequently, tax revenue. The motion passes unanimously. The deferral allows for more time to gather information and consider the implications of the evolving federal situation. This postponement is intended to ensure a well-informed and appropriate decision for the community.

Conclusion

That AI summary is close enough for me, and I listened to the whole four minutes.

If there were any specifics mentioned, about what’s supposed to happen between now and August 25th, both I and the AI missed them.  Just some boilerplate about getting more information, being responsible for this big decision, and so on.

Plus the notion that they can always defer a vote again, on August 25th.

The decision to defer a vote was unanimous.  Almost as if it had already been decided, outside of the public’s view.  Which it almost surely had.

The original recording can be found on Granicus, about 49 minutes into the recording of that Town Council meeting.

https://vienna-va.granicus.com/player/clip/1667?view_id=1&redirect=true

Any notion that Town Council Must Act NOW! has been quietly dropped down the memory hole (Post #2055).  So we’ve gone from “now or never” to “mañana”.  With zero comment on the change in the story being told to Town Council.  And zero repercussions for telling it.

Just another bit of mindless irrationality from the Town of Vienna.

Post #2086: Disbondment, my next road salt lesson.

 

The big boys — VDOT and its road-plowing bretheren — they salt the pavement when it snows.

So, why can’t I do the same, with my driveway?

Turns out, the reason VDOT salts the roadway is completely different from the reason I salted my driveway.

Huh.  Maybe you knew that, but I sure didn’t.

And as a corollary, recommended salt spreading rates for salting roadways have nothing to do with the amount of salt I needed melt the snow off my driveway.

Let’s not belabor this.

VDOT clears snow off the roads by plowing the snow off.  Their goal is to plow down to bare pavement when possible.  But they can’t do that if the snow and ice is stuck fast to the pavement.  VDOT uses salt to keep snow/slush/ice from adhering to the roadway.

Hence, disbondment.  The act of taking ice and snow that are frozen hard to the underlying pavement, and getting them loose.  Dis-bonding them from the underlying pavement.

Typically, VDOT’s goal is to use salt to melt just the very bottom layer of the snow/ice pack, where that touches the pavement.  They want to weaken that interface, so that the snow/ice can be scraped off with a normal snowplow.

I, by contrast, was using salt to clear the pavement.  That is, I wanted to melt the entire predicted thickness of the coming snowfall.  That, because I specifically didn’t want to scrape the snow and ice off the pavement.  I wanted them to run off, as salty water.  (I admit that I was right tired of shoveling, at this point in our most recent winter storms.)

Guess what?  If you’re only trying to melt that very thin interface between snowpack and pavement, a) you’re happy to use snow-melt pellets that just melt a little hole in the snow, until they get down to pavement, and b) overall, disbonding-then-plowing uses a lot less salt than melting the full thickness of the snow pack with salt.

A typical manufacturer recommendation for home use of de-icers (e.g., rock salt, calcium chloride pellets) works out to around one 50-pound bag of salt for every 1000 square feet.  Whereas the (reportedly) most common recommended rate for VDOT salting the road is about five pound per 1000 square feet.

 

Conclusion

There are a few fairly big conclusions, from the simple observation that VDOT’s use of salt and my use of salt are not at all the same.

First, just because VDOT salts the roads doesn’t mean I have an excuse to do it.  If for no other reason, what VDOT is trying to do with salt (disbondment of snow/pavement interface) has nothing what I’m trying to do (melt the entire thickness of the falling snow).

Second, you can’t take recommended salt spreading rates for road use, and apply those to melt the snow off your driveway.  It’s not nearly enough salt.  You will end up committing homeopathic ice melting, as described two posts back.

Third, using salt to melt snow in bulk — say, the full thickness of a light snowfall, off my driveway — that may be a remarkably stupid thing to do.  Again, per square foot, it takes vastly more salt to do that, than it does to treat the roadways.

While my road salt is but a minor contributor to the problems caused by society’s reliance on road salt, there’s no point in my adding fuel to the fire, needlessly.  Maybe in some climates, some locations, you absolutely have no choice but to use road salt on your driveway and walkways.  But Virginia, USDA Zone 7B, ain’t one of them.

I may take one more stab at this topic, trying to assess environmental safety of various road salts/ice melters.

And I may not.  Environmentally, the best choice is to use nothing.  So I’m not really feeling compelled to suss out various road salts’ claims of environmental friendliness or minimal impact on machinery and the built environment.

I may be done with salt.