There are several places to get water that most people do not think of right off. One of these is your hot water heater. You can get a special tool made only for turning off your hot water heater. That discourages it from ending up in somebody's toolbox, but a wrench will work. You can tape the special tool onto the back of the hot water heater to help keep it there for an emergency.
Another water source is the back of your toilet. The hot water heater water is fairly likely to be clean, but the water in the back of your toilet is not good to consider clean. I never use those automatic toilet bowl cleaners since I first thought of the idea of needing the back of the toilet for drinking some day. Most have instructions for accidental ingestion and the phone number of the poison control center.
If you are in an emergency, you may want to prioritize shutting the valves in and out of the hot water heater and the back of the toilet to trap the water in there. If you do that don't forget to unhook the float valve in the toilet tank so someone doesn't flush your drinking water away to the sewage plant.
If you live in a rainy or snowy area during a disaster you have an easier time getting water to drink. Snow can be melted and you will have clean drinking water. Skip the yellow snow, especially if it has someone's name written in it. They can drink that snow.
If it is raining during most disasters you can put out every container you can manage and catch your drinking water. If you want the water from your rain gutters and spouts off of your roof you will have to clean it before you drink it unless your roof and gutters are very clean.
If there is volcanic ash, a dust or sand storm, or nuclear fallout, your outside water sources are more of a problem. I will cover nuclear emergencies later. The ash, dust, or sand are just things that must be filtered to get clean water.
There are three main ways to clean water, filter it, heat it, or put something in it to kill germs. If you heat it you can either boil it to kill germs, or distill it to leave the germs and other impurities behind. Distilling can take a lot more fuel.
Iodine and chlorine are two of the most popular ways to put something in water to kill germs. You can get tablets or filters that have something in them to kill germs. I like the ceramic with silver because the silver is less hard on your body than the other things you put in water to kill germs. It kind of defeats the purpose if you kill yourself along with the germs.
If you want to filter, and you have an expensive filter or one that has a very limited amount of filtering it can do, you can protect the filter. That is done by using a pre-filter. That means something to take some of the bigger stuff out before it clogs up your expensive filter. That could be cloth. If you have a lot of big stuff in your water, you could run it through more than one pre-filter. Start with the biggest pre-filter first. That could be rocks then, pebbles, then coarse sand, then fine sand, for example.
There are some tricky military survival ways to filter or distill water, but this is too complex for this point in my blog posts.
I want to blog about storing water for emergencies next.