Viewing a single comment thread. View all comments

ErroneousRecipe t1_iwh6h70 wrote

Reply to comment by gunplumber700 in Recycled wastewater is not only as safe to drink as conventional potable water, it may even be less toxic than many sources of water we already drink daily by giuliomagnifico

I'm assuming you operate a CAS system?

I work on potable-reuse membrane plants and we see turbidity easily less than 0.1 NTU, and a lot of WW plants are seeing IPR.

DPR isn't far off, and was recently approved by Colorado regulators in that state.

26

gunplumber700 t1_iwhn5t5 wrote

I’ve worked at several plants and used most major system types.

Relative to DISTRIBUTION systems. There is a huge need for system upgrades to combat water loss. Having worked all over the US I can say that, imo, we should be focused on upgrading leaking/ crumbling distribution systems first.

Recycled water for drinking is a hard sell. I’ll believe it when I see it, when it’s being used in any significant amount.

11

scotus_canadensis t1_iwibvd4 wrote

I'm currently looking into recycling our wastewater effluent (kind of a background project right now). It's certainly not as clean as our well water, but it's feasible for use.

As you say, the first hurdle is people saying "ick".

The second hurdle is that our effluent goes into a reservoir used for irrigation, and the reservoir users would likely object to any new diversion.

3

gunplumber700 t1_iwiymd2 wrote

Im not really sure what are you getting at. Just because we can doesn’t mean we should.

Why make potable water from recycled water from wastewater when you can more than make up for slight demand increases with addressing water loss?

4

scotus_canadensis t1_iwizhnf wrote

I run a small system, with minimal loss. We go from a regular summer high of 1800-2000 m3 daily to around 700 m3 daily at this time of year. I'm comparing effluent recycling to the cost (and load on our local aquifer, which I worry about during dry years) of drilling new wells. There is not enough loss in our distribution system to offset the need for a new water source if any of our wells drops off.

2

outofideastx t1_iwjeco4 wrote

The obvious answer would be that treating wastewater more is cheaper than replacing hundreds, if not thousands of miles of mains. Treating wastewater more is also forever, while you're going to have to replace all the mains again in 50-75 years if you want to prevent water loss from skyrocketing again.

The city I work for is doing proactive leak detection (the program I run), DMAs, transient monitoring, meter calibration, etc. to lower water loss. We've been doing some of these programs for years now, and we were one of the first in the state to do proactive leak surveying. We still have high water loss. We're talking thousands and thousands of leaks over the course of a year. Our system is old, and we don't have the money to replace it all at once, nor the physical resources.

As I said, I run the proactive survey program, so I'm a big proponent of reducing water loss. That being said, cutting 1-2% of water loss is difficult to do, and very costly. Any city that needs to drastically reduce consumption in the next decade will only be looking at water loss as a longer term plan.

2

gunplumber700 t1_iwjkqeq wrote

And what’s the life of a wastewater plant? It’s not forever…

Failing to replace distribution systems pipes is failing to properly maintain a system. When customers complain about main breaks they have a point. When they complain about their bill being skyrocketing because they have to pay for upgrades because of managers that neglect their systems they have a point.

I don’t get why the industry is so ok with wasting such large volumes of water but “it’s hard” is the excuse I guess.

If you went to the gas station to fill up your cars 20 gallon gas tank and paid 25 but received 20 would you think it’s ok?

0

outofideastx t1_iwjr7uq wrote

I completely agree with you.

The people in power don't care, and they don't intend to spend more money on main replacement. And they'd rather spend a few million here and there, so they can put off spending a couple billion until they are no longer in office. At the end of the day, recycling wastewater would be cheaper than replacing the mains, especially when you add in the fact that many cities have to buy their raw water from an outside entity. In Texas, we buy raw water from water districts. There are cities here that built reservoirs before the water districts ever existed, but now they have to pay for raw water coming out of their own lakes. Recycling wastewater means you pay for it once, and use it over and over. If I discharge it into a river and then pick it up again downstream, I get to pay for it all over again.

Another thing to add perspective to the main replacement thing: Chicago alone has over 400,000 lead service lines. These lines are an active, major health risk and they are only removing dozens of them per year, when they should be doing thousands. If death and lawsuits aren't bringing replacements, they definitely aren't going to go replacing mains over some water loss.

Lastly, forcibly reducing irrigation is the lowest hanging fruit, as we can see on the west coast right now. Irrigation use is much more than 10% of the treated water in the south. Eventually, I'm hoping we will get on board with mass-scale desalination, hopefully powered by nuclear power.

1

gunplumber700 t1_iwjt5kj wrote

Nah that’s too smart for CA.

They’ll continue to take water from farms to send to a place with 10 million people to feed that has no farms. Then they’ll continue to allow pg&e (the big electric company out there) to start wildfires and burn down cities amidst water shortages all while not installing one of the safest and most reliable forms of power (nuclear).

0