Hacker News new | ask | show | jobs
by ethbr0 1797 days ago
Does California do reclaimed water?

I ask because experience in Florida (of all places, did not expect but was pleasantly surprised by!). They reprocess waste water back to non-potable, but sterilized standards, then run it out a parallel pipe system for irrigation use.

Makes perfect sense, especially since you effectively get (1) geologic filtration & (2) lower discharge volume treatment effort for free.

4 comments

Santa Monica has a dry-weather runoff recycling facility SMURFF, many millions of litres/day. Sells/trades it back to other LA cites, and locally for landscape irrigation and toilet flushing. They do guided tours, well worth going.
In ny hometown near San Diego the water from the local sewage treatment plant gets used by some nearby avocado farms.
Monterey county uses reclaimed water for agriculture, I'm sure there are others as well.
Irrigating non food crops hopefully? Idk anything about water filtration so maybe it’s fine?
Depends on the initial use. Water treatment is a surprisingly interesting (to me at least) rabbit hole.

You don't really control the upstream: someone flushing their toilet, or a laundromat dumping solvents down the drain?

But it's a solved problem to continually test the incoming water supply for the basics (pH, TDS). Plus intermittent checks for full workup (heavy metals, etc).

After that, it's a question of working it through the appropriate steps to get it to the state you want. Sort of like a continuously operating manufacturing line, except you get to blend the product at the end and only have to QA the blended result.

As someone quipped, "Dilution is the solution." Given enough volume and time, you can dilute even an arbitrarily large amount of lead to safe levels.

I've got news for you: wild animals shit on your food crops all the time.
My father was in livestock pathology and always had a chuckle whenever spinach or (insert product here) would claim field contamination.

His verdict: 9/10 it's rat feces at the processing or packaging plant.

But from a marketing perspective, field crop contamination is an act of God. Can't be helped.

Plant contamination would actually mean someone was at fault. And would require (expensive) changes.

The issue when it's people is it let's parasites enter a lifecycle which isn't complicated. Human feces is more likely to have parasites infectious to humans
Right but apparently that doesn't kill me. The question is what happens to industrial runoff in the water stream and if that has any effect on food safety.
I think (someone correct me if I'm wrong) US stormwater / runoff systems have to be isolated from sewer systems. Maybe an EPA requirement?

So reclaimed water is typically dealing with "anything anyone puts down a piped drain in their house."

(That said, I think there are also runoff processing requirements before discharge into waterways too)