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Trees on city streets cope with drought by drinking from leaky pipes

newscientist.com

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Re: Trees on city streets cope with drought by drinking from leaky pipes

#51

Post by mschuster91 »

Spooky23 wrote: post #48
btbuildem wrote: post #42

The city where I live estimates that we lose somewhere between 25% and 30% of drinkable water to leaky infrastructure. We've had something close to a drought this summer -- unseasonally long periods without rain. You can see the young trees on the streets and trees in the middle of large parks suffer from it - wilted leaves and leaves dropping earlier than usual. BUT, large old trees seem to be thriving - full canopi…

That’s really high. There’s either a big problem in your city, or they are making generous estimates to justify asking for more capital. 10-15% is more typical. In my region, the street trees are usually getting sewer water. Residential service in older houses are usually clay pipes with lead solder that the tree infiltrates. It’s not a problem until the clay pops and roots clog it. It varies a lot by region and juri…

Here in Germany, we estimate sewer infrastructure to last anywhere from 50-100 years, and water mains around 50-ish years. After that, it needs replacement or, that's the modern thing but it's a one-trick pony, re-lining.

The prudent thing would be to set aside and invest a tiny bit of money every year to fund a replacement, but unfortunately modern economic theory ("run lean") and manufactured income crises (aka, politicians going for lower taxes and utility rates) have led to a lot of infrastructure being utterly dilapidated and no savings left, and now we need to invest untold billions of euros raised from debt to keep it running.

Unfortunately, a lot of the deciders are already dead, and for those that still live, it's fallen out of favor to hold them accountable.

Re: Trees on city streets cope with drought by drinking from leaky pipes

#52

Post by mschuster91 »

londons_explore wrote: post #21

I wonder how much human health is impacted by these leaky pipes. I would like to see a city where pipes are guaranteed leak free, for example by making them double walled with high pressure air in the outer layer, and then seeing if disease levels in the city are lower.

> I wonder how much human health is impacted by these leaky pipes.

Not much, because the water mains pressure keeps nasty things from entering the pipe.

However, when the system is depressurized due to a power outage or due to running out of water, nasty things can happen (stuff entering the water pipes, oxygen from air bubbles causing rust), and that's why after such events boil-off orders are issued for a few weeks afterwards until it can be reasonably assumed that all pipes have been flushed and all air bubbles have gone.

Re: Trees on city streets cope with drought by drinking from leaky pipes

#53

Post by bluebarbet »

CalRobert wrote: post #35
x775 wrote: post #34

> Maple trees need to consume around 50 litres of water per day. Since street trees can’t get much of this from rainwater, which falls on concrete and drains into the city’s sewers, Poirier says the most likely explanation is that it is coming from Montreal’s leaky pipes, which lose 500 million litres of water per day. I feel like this is burying the lede. What can be done to reduce leakage?

Hopefully the lede, lead would be an even bigger concern.

The lede rendering is optional:

>The spelling lede (/ˈliːd/, from Early Modern English) is also used in American English, originally to avoid confusion with the printing press type formerly made from the metal lead or the related typographical term "leading".

https://en.wikipedia.org/wiki/News_style#Lead

Re: Trees on city streets cope with drought by drinking from leaky pipes

#54

Post by aziaziazi »

Spooky23 wrote: post #48
btbuildem wrote: post #42

The city where I live estimates that we lose somewhere between 25% and 30% of drinkable water to leaky infrastructure. We've had something close to a drought this summer -- unseasonally long periods without rain. You can see the young trees on the streets and trees in the middle of large parks suffer from it - wilted leaves and leaves dropping earlier than usual. BUT, large old trees seem to be thriving - full canopi…

That’s really high. There’s either a big problem in your city, or they are making generous estimates to justify asking for more capital. 10-15% is more typical. In my region, the street trees are usually getting sewer water. Residential service in older houses are usually clay pipes with lead solder that the tree infiltrates. It’s not a problem until the clay pops and roots clog it. It varies a lot by region and juri…

OP numbers aren’t only a city problem, IIRC [0] the numbers are close here in France. There’s a startup that try to tackle it : www.leakmited.com/en I applied there 3 month ago and they never responded. Can’t blame them but I’m a bit sad: it’s the dream impact-job.

[0] 20% apparently https://www.eaufrance.fr/repere-rendement-des-reseaux-deau-p...

Re: Trees on city streets cope with drought by drinking from leaky pipes

#55

Post by dingnuts »

buildsjets wrote: post #27
panarchy wrote: post #11

Or if you're a willow tree you make a leaky pipe.

Some genius planted a curly willow right in the middle of my house’s septic drain field. That tree cost me $20,000.

Same happened to me with a hackberry I didn't know was wild. Some genius added landscaping to make it look like a choice. You got off easy, I think after all was said and done I paid about the same out of pocket, but also was displaced for a long time due to the damages, and it cost insurance another $80+ grand that I'm sure I'll pay back over time in raised premiums.

Fun!

Re: Trees on city streets cope with drought by drinking from leaky pipes

#56

Post by closewith »

nashashmi wrote: post #32
londons_explore wrote: post #21

I wonder how much human health is impacted by these leaky pipes. I would like to see a city where pipes are guaranteed leak free, for example by making them double walled with high pressure air in the outer layer, and then seeing if disease levels in the city are lower.

Water pipes are under pressure. So outside water and pollutants do not infiltrate into leaky pipes. Unless you have a water shutoff. But those situations are minimal.

Globally they're definitely not minimal, nor are they unlikely even in developed countries.

Re: Trees on city streets cope with drought by drinking from leaky pipes

#57

Post by closewith »

likpok wrote: post #30
londons_explore wrote: post #26

Earlier quoted context omitted.

That way being 'sewage leaking into the ecosystem '? Followed by ecosystem being collected and put back into drinking water, most of which only has pretty lightweight treatment which doesn't even involve testing for any viruses which have snuck through.

The pipes are pressurized, so I would expect there to be limited avenue for infiltration. (Also, for sewage exposure, you’d need two leaks close together. Not impossible or anything, but much less likely.

Most of the world relies on drinking water collected from rivers downstream of other inhabited areas, so the impact of pollutants like sewage entering the watercourse does not have to enter a leaky water system to have a disastrous impact.

Re: Trees on city streets cope with drought by drinking from leaky pipes

#58

Post by pvaldes »

x775 wrote: post #34

> Maple trees need to consume around 50 litres of water per day. Since street trees can’t get much of this from rainwater, which falls on concrete and drains into the city’s sewers, Poirier says the most likely explanation is that it is coming from Montreal’s leaky pipes, which lose 500 million litres of water per day. I feel like this is burying the lede. What can be done to reduce leakage?

> What can be done to reduce leakage?

Do we really want that? Thousands of people are being killed each year by heat strokes. Keeping those trees alive by its environmental services is much more valuable in terms of lives and also energy saved. Maples have soft big leaves but also reduce the asphalt temperature by 5-10 degrees. If required just plant a tree species that can live with less water.

Re: Trees on city streets cope with drought by drinking from leaky pipes

#59

Post by dmbche »

Spooky23 wrote: post #48
btbuildem wrote: post #42

The city where I live estimates that we lose somewhere between 25% and 30% of drinkable water to leaky infrastructure. We've had something close to a drought this summer -- unseasonally long periods without rain. You can see the young trees on the streets and trees in the middle of large parks suffer from it - wilted leaves and leaves dropping earlier than usual. BUT, large old trees seem to be thriving - full canopi…

That’s really high. There’s either a big problem in your city, or they are making generous estimates to justify asking for more capital. 10-15% is more typical. In my region, the street trees are usually getting sewer water. Residential service in older houses are usually clay pipes with lead solder that the tree infiltrates. It’s not a problem until the clay pops and roots clog it. It varies a lot by region and juri…

My city loses about 30% of the water going through it's pipes, including leaking wastewater directly into rainwater drains ( left untreated).

I believe some of the plumbing was wood pipes in select very busy parts of the city until somewhat recently, as it was a nightmare to replace.

Re: Trees on city streets cope with drought by drinking from leaky pipes

#60

Post by bombcar »

2OEH8eoCRo0 wrote: post #20
bombcar wrote: post #18

Earlier quoted context omitted.

Cast Iron’s worse than plastic because they always leak a tiny bit and that means that the roots can “smell” the water and go for it. Plastic either is impervious or completely fucked.

I get tree root intrusion where my newish plastic sewer main joins the street sewer.

Yeah joints are always the problem.

Which is why you want the joints to be someone else’s problem.

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