Published: September 25, 2020 - by Larry Weingarten

Categories: Domestic Water

health nation

Clean, safe water is what we expect and need running from our taps, but there are a number of things that can get in the way of that goal. I’m not a scientist, just a plumber who brings field experience to the discussion of safe water. There are good resources out there to help us understand water quality issues and how to deal with them. It includes some of those resources for those who want to take a deeper dive.

So, what are the ways water can become unhealthy? First, water, (also called the universal solvent) can pick up some of whatever it touches. Water is creative and has a number of ways it can do this. If it’s running through copper pipe for example, it can pick up some copper and give that to you. If it sits in copper pipe for a long time, it can deliver more, even unhealthy amounts of copper in your water. Let’s say you soften your water. This basically is replacing calcium and magnesium hardness with salt. Too much softening can strip the protective layer of hardness off of the copper pipe, or prevent it from forming, exposing the copper. The water itself might be “hungry”, which means it’s so clean and free of hardness or other stuff in it, that it’s more aggressive in wanting to dissolve what it touches. Distilled and rain waters are good examples. So, both over-softened and naturally soft waters speed corrosion of the pipe, and you know where that loose copper is going… straight out of the tap into your drinking glass!

If you’ve just remodeled, put in new copper pipe and you soften the water, wait for about six months before using the softener again. This will let a thin film of scale build-up on the pipes and protect them. The National Association of Corrosion Engineers suggests leaving 60 to 120 parts per million of hardness in the water after softening, to prevent pipe damage. Also, if the copper pipe was soldered years ago using leaded solder, that lead might make it to your tap. If water runs too fast or too long in the copper line; for example, an always-on recirculation line with an oversized pump, you’ll get erosion corrosion, where the copper is abraded away. Acidic or corrosive water itself can eat up copper. There are a number of interesting ways to damage copper plumbing and put the residue into your water glass! The Copper Development Association has lots of good information. Treated nicely, copper is amazingly durable and long lived. We just need to know how to be nice to our copper pipes.

If the brass fixtures in your home are older, the water can pick up lead from that brass. First thing in the morning is always a good time to let water run for a few seconds before filling your glass, as that water has been sitting in contact with brass all night, and testing repeatedly has been shown the first flush of water can have high lead levels in it. Guess what, galvanized pipe, which is steel pipe coated with zinc, can have some lead in it too. Lead helps the molten zinc flow better, to coat the pipe nicely. I understand that some jurisdictions no longer allow galvanized pipe to be used for water lines because of this.

Another interesting way bad stuff can get into the water is by traveling through the walls of the pipe! This can happen with PEX pipe that’s buried in the ground. If the prior owner of your house used lots of weedkiller or loved working on cars, the pesticide or automotive fluids could leach through the plastic pipe into the water. It’s a good reason never to directly bury PEX, but always to run it in conduit. That can make servicing the line in future easier and keeps the sun’s UV rays away from the PEX as well, where it comes up out of the ground. Also, plastic pipe like PVC has “plasticizers” in it which can get into the water. And PVC cement can often be smelled and tasted in the water after working on the pipes. Yummie!

Let’s imagine you have hot water in your house. It’s not that uncommon. The hot water comes from a water heater (not a hot water heater… it’s really a cold-water heater!). If it’s a glass-lined tank type heater (most are) there will be a sacrificial anode in the tank to keep it from rusting. If that anode is made of aluminum, (many are) it will be putting aluminum corrosion byproduct in your water. Being a curious person, I had water from the center of an undisturbed tank tested for aluminum and found double the California State EPA limit for aluminum. I have yet to see aluminum pills in the health food stores, so think about replacing that anode with a magnesium one or even a power driven one. Being cautious also, I like to think about health-related things as guilty until proven innocent. See discussion of the “Precautionary Principle”, below. Magnesium pills are available because of the health benefits they bring. Yay! This is a little hint that magnesium anodes might be safer to use.

So far, I haven’t said a word about bugs. Bacteria and other bugs really like the insides of pipes! And we are getting better at building plumbing systems that encourage the bugs to live long and prosper. This is in part because we oversize the lines for the actual use they get. Plumbing codes and energy codes don’t seem to talk with each other, so we size pipes by code, for flow rates the pipes never see. There are circumstances where a 1/8” tube would meet flow requirements yet ½” lines get put in. With big lines and low flow, biofilms and the bugs that live in them have every chance to flourish.

One reason why the plumbing codes are so out of whack with reality may be that long ago, we realistically had only steel pipe to play with. Plumbers knew that over time it would fill with rust, so they would increase the line one size. This way their clients would still get decent water flow years into the future. This was done before there were any plumbing codes and likely shaped how code was written. We have different plumbing materials now and low flow fixtures. It actually would cost less and be easier to install smaller plumbing that is safer, works better, and conserves resources. Hmmm!

Good plumbers have known for a long time to eliminate “dead legs” in plumbing. That’s because water can stagnate in these areas and make swamp water that bugs just love growing in. Oversizing pipes accomplishes the same thing while also wasting water, which may have been heated, so it’s wasting energy as well. That’s O for three. What a deal? Additionally, galvanized pipe is rather rough on the inside and only gets worse with time. Copper is fairly smooth and PEX is smoother yet. The roughness gives a toehold for the biofilms to hold onto, making it harder to disinfect the system. Better is to use smaller diameter piping or tubing so that flow is faster, scouring walls of the pipe. A trick for doing this with PEX is to avoid the use of 90s or other fittings that force water to turn sharply, and use bend supports, and fittings that get inserted into expanded tubing. These measures reduce friction loss and pressure drop, giving better flow. Also, hot water will arrive faster if there is less volume of water in the system between the heater and tap. Gary Klein has written extensively on these subjects here. Having smooth piping and no dead legs uses up the chlorine residual or other water treatment more slowly, so bugs are less able to grow in the lines in the first place.

One place in plumbing that often encourages bugs to grow might be surprising… it’s the water filter! Water flow slows down in the filter and there are plenty of places for bugs to hang out, party and snack! This is because the stuff the filter is intended to filter out, that accumulates on the filter surface is largely organic food the bacteria enjoy. If your filter has a clear housing, sunlight can also help power the bugs. You’ll often see these filters looking green, like algae is growing there, because it is! Filters commonly don’t get changed for long periods of time. That makes the bugs even happier, because then, they can build entire cities, rather than just campgrounds. So, if you need to filter your water, try using an opaque filter housing and changing filter elements regularly.

With all this talk about bugs, Legionella comes to mind. It’s a growing concern as cases diagnosed yearly have increased about fivefold in the last twenty years. This may be in part due to better testing and in part because of plumbing design. This bug is primarily a concern for the old, young or those with weak immune systems. Legionella has long been a difficult discussion for plumbers and engineers. This is because a good way to control it is to turn the water heater up to 140 degrees F., which greatly increases the scalding risk. It’s a tough balancing act.

In Europe, they are far more cautious about adding chemicals to the drinking water than we are here in the US. They abide by a thing called the “Precautionary Principle”. From Wikipedia: {In economics, the Precautionary Principle has been analyzed in terms of "the effect on rational decision-making", of the interaction of irreversibility and uncertainty.} Irreversibility and uncertainty; what an interesting pairing!

We don’t know the long-term effects of our actions, like chemical water treatment, yet the risk of doing irreversible damage to people’s health must be taken seriously, even though it might be years in the future. The incidence of Alzheimer’s disease has increased. Stats I found say that between 2000 and 2013, the rate of death from this disease has increased by 71%. If you’ve ever been up close and personal with Alzheimer’s, you know what a thief and a nasty disease it is. That’s why I remove aluminum anodes from new heaters and install magnesium. I don’t know with certainty that the aluminum is damaging people’s health or contributing to Alzheimer’s, but I don’t ever want to learn that I could have helped stop folks from getting that disease and didn’t act.

Years ago, I found an interesting booklet from a doctor advising no aluminum cookware. It’s sobering.

Now, getting back to water treatment in Europe, they seem to use guidelines from the World Health Organization, which has made available a book on many aspects of water treatment. From a quick skimming of it, although they understand the benefits of chemical water treatment, they do a lot with filtration and seem to have less trust in chemical disinfectants than we do in the US. We do know that there are unhappy byproducts of chemical treatment and it might be that the WHO is trying to protect people from those nasties.

There is a lot to understand and keep track of in the quest for good water. Water that comes from a municipal water supply used to be thought of as pristine, or something we could simply trust with no further consideration. It was seen as our right as citizens of the USA, and everybody knew it! Since Flint, Michigan made headlines, that perception has changed. Politics got in the way of physics, and if it happened in Flint, where else might trouble be brewing? As citizens we also have responsibilities. Why not check up on your water? Get a “Water Quality Report”. Water purveyors are required to produce these yearly. Read through what’s in your water and if there’s anything you don’t understand, ask around and research it. If you want to go a step further, have your water tested, both where it comes into your home and from a tap inside, preferably first use in the morning. Now you’ll be able to see if the plumbing in your home is creating a problem.

If the water is found to be lacking, there are lots of things you can do to make it better. Maybe just putting a reverse osmosis system under the kitchen sink will suffice. That way you’ll have clean water for cooking and drinking. In many parts of Great Britain, they have cisterns in the attic. This is where water from the main line goes and then drains down to the taps by gravity. It’s open to the atmosphere, very much like a toilet tank, so nothing prevents airborne things from getting into it. Everybody knows that the only tap in the house you should get drinking water from is the cold kitchen tap, because it is piped directly from the main, rather than coming from the cistern. If they can learn that in Great Britain, we can learn to use a reverse osmosis tap in the US for any water that we take internally. And, really, what’s the problem with having different qualities of water in the home as long as they get used appropriately? We likely don’t need to use drinking quality water to flush toilets!

There are lots of other water treatment options available if needed. A few places to find more information include; The American Water Works Association (AWWA), the US Environmental Protection Agency (EPA), and Consumer Affairs.

So, water is pretty interesting stuff! It can do all sorts of interesting or even surprising things. I’ve given you a lot of research/work to do, so should you want a fun and interesting break from your labors, here’s a completely different perspective on water and what it does.

Food for thought.