> I certainly wouldn't go swimming in one of the water wasn't cycled regularly
Once again speaking as someone who has maintained pools for a while, if the water was properly monitored and maintained I probably wouldn't mind. I'd absolutely take a pool that's actively properly maintained but hasn't had a full replacement in a few years over one that's poorly maintained but was fully drained and refilled a couple of months ago.
From experience while my son was swimming competitively, they had to drain most of the pools he swam in completely more than once a year because of various contamination, in addition to the ongoing cycling...
I can't imagine the state they'd be in after a year.
Once again, if its monitored and maintained properly, sure why not? Partial cycling when things that can't be filtered get too high (like TDS or CYA for an outdoor pool) but otherwise make sure sanitization is happening properly, pH and other metrics stay balanced, and good filtering is happening, I don't see a problem.
> more than once a year because of various contamination
Sounds like that falls into the "unlucky" category.
If its that you don't like thinking about tons of other bodies have touched that water you're swimming in, remember that dinosaurs pooped in much of the water you're drinking today.
> Partial cycling when things that can't be filtered get too high (like TDS or CYA for an outdoor pool)
Partial cycling in a high traffic environment seems like it is clearly ending up being a lot of water when every number I can find suggests it is generally expected to add up to several times the total pool volume per year.
> Sounds like that falls into the "unlucky" category.
To me it feels like it falls in the "expected" category somewhere that is dealing with hundreds of swimmers including small children every day.
Keeping in mind this was across dozens of pools - he swam competitively, not a one-off or rare occurrence in a pool or two.
It seems like we're mixing up terms here and miscommunicating. I thought we were talking about actually replacing the water here (as in, down the drain, fresh water from the tap), not just filtering as in recycling water through filtration systems. The total volume of the water should go through filters every few hours. I'm 100% not for the idea of only "partial filtering".
> To me it feels like it falls in the "expected" category somewhere that is dealing with hundreds of swimmers including small children every day.
Nah, that is definitely not normal to have to completely replace the water multiple times in a year because of water contamination events happening. The water can usually be sanitized. It might require a day's worth of hyperchloronation, but not often an entire drain and fill. That will happen often, probably several times a year. Usually only if your CYA is too high will it require you to actually drain a significant volume of water, which I agreed was one of the reasons to at least do a partial drain and really only applies to outdoor pools. Doing a hyperchloronation will likely increase your TDS, which won't go down until you drain those contaminates. But usually you can get those numbers back in an acceptable range without having to drain and fill the whole pool.
If the pool was properly maintained, what state do you expect the water to be in after a year without a total drain and fill? Do you have experience actually maintaining a pool?
> It seems like we're mixing up terms here and miscommunicating. I thought we were talking about actually replacing the water here (as in, down the drain, fresh water from the tap)
We are. I changed it while you were writing.
Everything I'm seeing suggests typical loss to backwash of the filters for a short course pool is in the 5k - 10k liters of water a day range, possibly less if you invest in expensive additional filters. 5k a day is ~1.8 million liters a year.
To get below a full replacement every year for a small short-course pool, you need to lose less than 1370 liters a day, or ~1.4 m^3
You're shifting things from normally needing to fully drain and fill the pool multiple times a year from specific contamination events to now talking about routine backwashing events, which I agree do happen as a part of normal routine maintenance (a part of the "partial drain" and "good filtering" I was talking about before).
I agree you'd probably use something like 5-10k liters of water for a backflush for filters that size, but that wouldn't normally be a daily thing. The amounts needed here would be highly variable depending on a wide range of factors.
I still stand by if you're having to actually fully drain and refill your pool multiple times a year (as in, an actual drain and fill, not slow partial replacement from weekly/every other week filter flushes) you're either very unlucky or you don't know what you're doing maintaining the pool.
This went into the weeds a little bit, but I've tried going over the figures again. I'm not sure if I'm missing something here or someone got some units wrong somewhere, but data centers seem to use far more water.
A medium size data center consumes 300k gallons of water per day [0]. That's over 400 million liters per year.
Even if we go with the highest estimate vidarh gave of 1.8 million liters per year for a full-size olympic size swimming pool, that's a tiny fraction of what a typical data center uses.
> A medium size data center consumes 300k gallons of water per day
Not always true. This can vary greatly based on datacenter design. A medium sized datacenter proposed near me was planned to only use 300 gallons a day for example.
Your source even points to this being highly variable, assuming you pay attention to their wording.
> Large data centers can consume up to
"Can consume", "up to". Not some hard truth that they will consume that much.
Fair point. If you divide the 163.7 billion gallons annually among the 5426 data centers, the figure does come out lower at ~30 million gallons or ~100 million liters annually. That's still far, far larger than the largest swimming pools.
Once again speaking as someone who has maintained pools for a while, if the water was properly monitored and maintained I probably wouldn't mind. I'd absolutely take a pool that's actively properly maintained but hasn't had a full replacement in a few years over one that's poorly maintained but was fully drained and refilled a couple of months ago.