If anyone here has contemplated using pool water for emergency drinking, I've done a fair bit of research on it.
I'm not what you'd consider what folks these days are calling "preppers," however I am a very pragmatic, conservative degreed mechanical engineer, that also happens to be an Eagle Scout.
More than 36 years ago, when I earned my Eagle Award (Scouting's Highest Achievement and Honor), little did I know what I learned back then, about Emergency Preparedness, would be mocked, or over-looked as some sort of doomsdayish sort of thinking. I don't particularly like the labels of preppers for a lot of reasons. But we learned simply about being prepared for a lot of things that are frequently over-looked by people in an every day rush to "live their lives" gets you into the sort of trouble that can be easily avoided with some planning and preparation. Its what some of us call common sense, growing up, and being responsible citizens and adults. For example, many flood aftermath victims of Sandy, could be avoiding a lot of the problems they face, via basic emergency preparedness.
Thinking about having pure and clean drinking water is just not something that comes top of mind, unless you've been through a disaster or gone to some country like Mexico, drank their water, and then experienced painful diarheeria or worse total dehydration. We take clean water for granted here mostly in the US.
But just like having health insurance, car insurance, or homeowners insurance, being prepared to have pure and safe drinking water, no matter the situation is simply sound and practical thinking. Why ? Because if you wait until you need it most, when you don't have it, your life can become quite the disaster and make ANY natural disaster 100 times worse for you, than your neighbor(s).
Anyway, there are a number of credible sources on the topic, but if you have the right purification (not just filtering and there is a huge difference between those two words when it comes to drinking water), your pool is able to be used as any other water source the government, Homeland Security, and other credible and informed sources recommend.
Probably the most practical purification for emergencies, particularly if you have a family, is a gravity fed water purifying system, that can also be used for daily drinking during non-emergency situations. Berkey and its predecessor Doulton, provide systems that purify up to Log 7 water quality, remove chlorine, and many harmful chemicals including flouride, MTBE, VOC's, arsenic, and all sorts of bacteria and viruses down to micron levels and make the water far cleaner than what you get out of your tap, even with your own separately purchased common carbon or RO filtration.
Flouride is a major contributor to a lot of illnesses and health problems, yet people accept drinking it everyday. Tap water and toothpaste being your biggest source of exposure.
Anyway, when I prepare or plan for the unexpected, I look for useful 'tools' or devices that have multiple everyday practical uses. (as much as possible). That way, its no big deal to using them when disaster strikes, and the family takes it all in stride, and hardly notices much in the way of lifestyle changes. Of course some changes are going to happen, but why have the most important element for the human body's survival, be up in the air and in jeopardy at any time ? Having a Berkey system (or other appropriate gravity fed, with appropriate purification) can provide you with the best and most pure potable water, economically, for everyday drinking, coffee, and cooking, while also being perfect to filter your pool water if that day were to ever come. Their Black Burkey's (cartridges) will last 6000 gallons or longer, and the replacement costs are going to be less than any other system or especially bottled water that most people buy, and then pollute the planet with plastic bottles. You can add separate PF2 flouride and arsenic filters within the same system.
For around $300 for an entire system, (which mostly looks like a large cafeteria style stainless coffee pot) (and most of you pool owners drop $300 or more in a heartbeat on many pool related items) the value of pure and safe drinking water at all times is absolutely priceless.
And you will likely never need it for an emergency depending where you live, but using it everyday might still actually save your life, since it purifies water to levels most people rarely ever experience.
After something like Hurricane Sandy where it's evident they are having problems with getting everything from water to fuel for vehicles, power to heat their homes, while its top of mind and you see the desperation, now is probably the best time ever to actually act, and do it. Otherwise you will procrastinate, put it off, and never take action. Make the investment in your health and safety. Its water related. You LOVE water. You know its value ! You are a pool owner !
And I know pool owners like here at this forum are very health and safety conscious, especially the ones concerned about chlorine on the EXTERIOR of their bodies, who use the BBB method. As always, do your own research, and don't exclusively rely on what I am suggesting here.
P.S. and your pool might also become known as a valuable neighborhood preparedness resource in a time of emergency, and not just for being the best people on the block who have awesome pool parties. ! (of course you'll have to educate your neighbors to invest in their own gravity feed purification system). That's not a bad thing either.