Drinking Water Is Staying in Pipes Longer
citylab.com
citylab.com
>A utility in North Carolina serving 300,000 customers with 1,100 miles of main calculated water ages ranging from 2 to 75 hours throughout the distribution system using a fluoride tracer study (DiGiano, Travaglia and Zhang 2000).
> A Midwest utility with a service population of 800,000 and 2,750 miles of main recently found based on a hydraulic model that the water age in the distribution system was typically less than 80 hours while several sites exhibited a water age up to 150 hours (Vandermeyden and Hartman 2001).
> One California utility found water ages exceeding 400 hours in certain areas of the system, particularly dead end areas, under minimum day and average day demand conditions (Acker and Kraska 2001).
> A Canadian utility serving 24,000 people with 86 miles of main estimated water age using a hydraulic model and found that dead-end nodes had a water age ranging from 300 to 600 hours under average day demand conditions (Prentice 2001).
"How long is too long?" It depends, apparently, on what the pipes are made of, how old they are, how corrosive the water is, (Which is what caused the Flint disaster) etc.
https://en.wikipedia.org/wiki/Chloramine
The main problem is that they are potentially more carcinogenic.
The rarely talked about, but potentially more serious problem, is that chlorine and chloramine are difficult to remove from water by letting it stand or boiling it:
https://www.sfwater.org/Modules/ShowDocument.aspx?documentID...
https://www.physicsforums.com/threads/does-boiling-water-rem...
https://www.morebeer.com/articles/removing_chloramines_from_...
It looks like activated charcoal filters are the best way to neutralize it, but I'm having trouble finding numbers for how effective they are at it.
https://homebrew.stackexchange.com/questions/3447/what-are-t...
> Despite the challenges posed by shrinking federal investment and rising costs, America’s water systems strive to maintain affordability. As such, many water systems have historically underpriced the services they provide to keep water rates low.
The result is a backlog in investment approaching a trillion dollars.
See complaints about how rooftop solar customers don't pay their fair share of fixed grid overhead. Wouldn't be a problem if you billed people an accurately priced fixed charge, plus usage charge.
Even worse, the fixed cost varies enormously depending on the particulars of any one residence (older infrastructure costs more to maintain, for example). So it's really hard to come up with a truly fair scheme for distributing these costs— pretty much no matter what you do, some households will be subsidizing other households. If not on their water bill, via their income taxes.
The true(st) fixed costs are things like the last mile to your house, that only you benefit from.
Though, i suppose showering habits have changed. Oh, but toilet flush and low flow stuff has happened to everything.
Public supply usage hasn't changed meaningfully for a few decades.
Automatic clothes and dishwashers are far more common now, and today’s models are more efficient than than manually performing the same task by hand. Simple automated drip irrigation systems can be had from any local hardware store, customizable to deliver the exact amount of water needed to plants at the most optimal time to minimize wasted water from evaporation. And low pressure shower heads are everywhere now; the ridiculous hurricane bathroom shower of the 70s and 80s is only fond childhood memory.
I've lived places where the fixed amount of my water bill was maybe $10-$15/mo while a unit (~750 gallons) of water was about $5. My current home, at the other extreme, has almost $90/mo in fixed charges while a unit of water runs about $1.
Not nearly the same incentive to conserve water but I am much more confident that my city will still be able to service the infrastructure 20 years from now.
Our population density is very much lower so transmission costs per connection are very much higher.
I grew up in an area where the length of transmission line per home would easily have been calculated in miles. I currently live in an area where transmission line per home would be measured in feet or maybe inches.
One can imagine a different model, which does not require the government to set prices. But that doesn’t mean the government isn’t bad at setting prices. And it would be a dramatic and fundamental change to the wide variety of government services based on usage fees. There are also intensely good reasons to have usage fees. Otherwise, you encourage waste and sprawl.
Federal funding is a red herring. Water is an archetypal municipal issue, like local roads. The federal government has targeted programs for disadvantaged communities, but in general cities (and certainly states) should be able to handle their own water and sewer systems.
[1] You see similar problems in governments determining public pension contributions. That's effectively the government setting a price required to buy into a pension system that guarantees certain benefits. Governments universally set that price too low, resulting in the public pension disaster we have today.
(Actually, I see no reason why market forces would get the price "right" here, but even if they did it misses the point--there is no reason to allocate water to people based on how much money they can pay for it. If you cared about this sort of thing a rationing system would make much more sense. The idea that the infrastructure has to be funded directly and primarily by water usage is just baffling to me, especially when--as numerous commentators have already pointed out--it doesn't really work that way in a lot of cities).
The water/sewer infrastructure crisis is on the same order of magnitude as the public pension crisis (into the single-digit trillions of dollars).
> What exactly is the benefit of getting pricing "right" here? Avoiding water wastage? Environmental benefits?
All of the above. For example, when connection charges are too low, people are incentivized to engage in greenfield development rather than infill development. Having the federal government further subsidize things only exacerbates that problem.
> I'd wager that a group of environmental scientists could find a "correct" price that addresses these concerns much more accurately than could market forces.
They have. And elected municipal entities uniformly ignore those results.
(0.5% of the US economy over 10 years is a massive amount of resources but would have ~0 negative impact if diverted from other economic activity to water infrastructure)
Why does everyone seem to take this for granted? I've drank tap water my entire life, living in 5 different states. It tastes good, is cheap, healthy, and environmentally friendly compared to any other option.
Sure, there are examples of failure. Are they significant examples of the model being bad? Any system with thousands of examples is going to have a few failures. It doesn't mean the system is bad.
That's like saying "cities and states are able to pay retired teachers now, so what's the problem?" The problem is that the government under-invested in the infrastructure for decades and now those problems are coming to a head: https://www.bbc.com/news/world-us-canada-39410561 ($1 trillion needed to shore up "aging" water infrastructure). It's the same problem that is pervasive in municipal infrastructure. You can get away with under-investing, until you can't. It's the same reason NYC's subway has melted down, DC's subway is on fire, etc. Nationwide, infrastructure--which is mostly a municipal responsibility--is underfunded to the tune of $5 trillion by 2040: https://www.reuters.com/article/us-usa-infrastructure-idUSKC.... That is the direct result of policies that give people what they want--more infrastructure at low prices. It works until it doesn't.
> Sure, there are examples of failure. Are they significant examples of the model being bad? Any system with thousands of examples is going to have a few failures. It doesn't mean the system is bad.
Pretty much every major city is an example, from D.C.'s inability to upgrade civil war era sewers that are polluting the Potomac to Chicago's inability to upgrade lead piping that is poisoning children.
Characterizing this as categorical failure, with the implication that the whole system should be thrown out and drastic measures taken, seems wrong to me.
That’s just water. Other infrastructure has been neglected by state and local governments, leading to a $5 trillion backlog (including water). That’s 10x total US annual spending on infrastructure. Trains have to slow down when it rains in the DC/Baltimore area because the 100+ year old tunnels under Baltimore are leaky. DC’s metro trains were self driving when they were built in the 1970s. They had to shut off that system because the supporting track infrastructure had been allowed to degrade so much. New York’s subway has basically melted down. Ridership in DC and New York, the two biggest transit systems in the country, has been declining despite population growth because the system can’t provide the level of service it did even 20 years ago, due to decades of neglected maintenance.
Meanwhile, lead pipes are poisoning kids in Chicago, and DC’s civil war era sewers dump untreated raw sewage into the Potomac when it rains. These systems needed to be upgraded decades ago.
I’m not advocating getting rid of the entire system. I’m pointing out that it goes far beyond a “few examples of failures” as you claimed in your earlier post. It’s a systematic problem that affects almost every municipality that allows political bodies to set prices for services. They systematically set them too low to allow long term sustainability.
Estimates of long-run demand elasticity are over 0.5: http://www.allianceforwaterefficiency.org/uploadedFiles/Reso... (p. 3). That means say doubling water/sewer rates could reduce demand significantly, while raising revenue to address maintenance back logs. The effect on the poor can be mitigated by, e.g. regulated pricing for the first X gallons per month.
Good point about the elasticity, I should have said it's very inelastic up to the point where the necessity is met, and then it becomes much more elastic.
The last thing a city wants is a bunch of people who can't afford water, and decide to drink from the local stream, and the city has to pay to treat cholera or some other outbreak.
There are other ways of paying for infrastructure. Not everything needs to be fully paid with usage fees.
Heavy users of water currently pay far less than what they should and are receiving taxpayer subsidies.
I don't think we need to do anything so extreme, just charging by usage will result in regular water users paying less overall, and heavy water users paying more.
https://www.latimes.com/socal/glendale-news-press/news/tn-gn...
https://lbpost.com/news/city-settles-lawsuit-over-water-rate...
https://www.sdcwa.org/adoption-illegal-mwd-rates-forces-four...
https://www.sfchronicle.com/bayarea/article/Millionaires-sue...
Another, related problem, is the issue of maintaining state pensions and other entitlement programs.
Social Security in the USA, for example, has a negative ROI. For it to work the government has to take money from younger working people in order to pay for older retired people. As the population shrinks you have less and less young people being forced to support the larger number of retired people.
All these sorts of programs have the same problems. They were designed in a era were it was assumed that people died off as a higher rate and people were born at a faster rate. As those trends gradually reverse then all welfare/entitlement programs are becomingly increasingly insolvent.
....
This sort of stuff is why the Soviets had to institute travel restrictions and a sort of passport system in the USSR; you can't have effective long term government planing with a rapidly shifting population.
My old grand mother city is one of them: streets are full of closed shops, but the infrastructures are in perfect shape. Roads are pristine. Water is clear. Electricity is never ever missing.
The general decay in France is going to be at a much slower rate then some place like Detroit. This means that the increasing tax burden, crumbling infrastructure, and financial crisis not only are much less noticeable, but governments have more time to react and mitigate the issue.
The reason why places like Flint are impressive in their decay is because the rate of change in population is so extreme.
And from experience, a lot of US roads suck, even in rich and dense area such as the Bay.
So while I agree with the logic of your point, I think the core of the problem lies elsewhere.
You can solve that entire problem with a few years of inflation. There's nothing, in principle, wrong with a guaranteed return-until-you-die investment, as part of a retirement strategy.
It's a smart part of a diverse retirement portfolio (Especially when compared with a 100% commitment to the guaranteed-contribution, variable-return investments of 401ks). I wish I could invest more than 3% of my income into SS - and I expect to take a haircut on that investment.
The thing is, all the same risks of Social Security (People living longer than expected, investment returns being lower than expected, a prolonged recession emptying out the fund, inflation turning your guaranteed returns into 'only-good-as-toilet-paper-money') apply to them, but even moreso (Because they cannot count on continued buy-in, unlike Social Security).
How can they know what the necessary level is?
Perhaps they should institute higher prices for those further away from the distribution point.
I don't think it's that simple. If it were, then why do we see similar problems in the areas where the population is growing?
In the UK, pipes are sized based on the needs of the domestic demand, while capacity for fire flow is not considered. While in North America the opposite is done, where the network, including capacity in tanks and pressure within the network, must take into account fire flow requirements. (The attached EPA document goes into this in more detail)
While a UK residential street may be supplied by a 100mm main, the same street in the US may need a 200mm main. That's a four-time increase in volume that needs to be turned over in the pipe for just a little street!
I have seen design documents for North American towns requiring flow rates of 50-90l/s to protect a single house. When I tell my colleagues in the UK about this they laugh and ask if I'm joking and if the fire bridge is aiming to simply flatten the house to stop the fire.
Pressures in North American networks are also higher than in the UK, once again to meet fire flow requirements, which leads to higher background leakage and bursts within the network.
High age of water is an issue that will affect most North American water systems regardless of if they are shrinking or growing.
The only graphic in this article is "city shrinkage", which is then conflated with water age, which is then related to water problems. But I suspect these things may not be as linearly connected as the authors imply, specifically because of factors like the chemistry of incoming water, as exemplified by the Flint situation.
Also, water systems can have vastly different flow rates, pipe sizes, and other parameters that influence water age, not just population change.
So, is there better data? Can we actually show a relation between city shrinkage, water age, and water problems? If this data exists, why wasn't it presented? If this data doesn't exist, why is a relationship suggested?
And you will still have to maintain the pipes. Your solution would reduce costs per mile, but you still have a lot of mileage to maintain with a shrinking population.
To keep from running out of fresh water, we'd need to stop growing the population, or stave off the amount of water used for agriculture, or re-engineer all our wastewater systems for treatment and reuse, or build massive amounts of expensive desalination plants along with a massive global distribution network. All of these are possible, but we also have to actually start the process before it becomes too painful.