Many municipal water supplies are disinfected with chloramine now, not chlorine. (That's Texas law, for example.) The difference is that chlorine evaporates, while chloramine does not. It can only be removed by chemical reaction or charcoal filtration. For that reason, I avoid tap water as much as possible. But one nice thing about it in a survival situation is that, based on personal experience at least, it does not go bad.
I think in addition to dry beans, rice and such, that I would have some home canned versions of these in case water is at a premium. Beans, rice, quinoa, etc., require lots of water, and if it is in short supply you are going to be in trouble. Having HOME canned versions of these will mean that until water is more readily available, you can eat and have protein available to you. I’ve heard of others ‘canning’ water, too!

Not to mention the “year without a summer” that happened after the eruption of Mt. Tambora in the Dutch East Indies in 1815. The resulting ash and smoke plume blocked the sun enough to lower the average temperatures only by a few degrees. It was enough to trigger famines in North America and Europe for several years until temperatures gradually normalized. If the Yellowstone caldera erupts the smoke and ash would block the sun much as would a nuclear winter and would trigger even worse famines and suffering from people trying to cope with minimum if any infrastructure for heat, water, medical, etc. just for the simple reason that we’ve got way more people now and more of us live in urban areas.

For global catastrophic risks the costs of food storage become impractical for most of the population [54] and for some such catastrophes conventional agriculture would not function due to the loss of a large fraction of sunlight (e.g. during nuclear winter or a supervolcano). In such situations, alternative food is necessary, which is converting natural gas and wood fiber to human edible food.[55]
It's reported that US and British “advisers” and “instructors” to the  Syrian opposition forces are trapped in Idlib. There are frantic  attempts by the USA and Britain to ask Turkey or Russia to help evacuate these troops. But Britain has refused to co-operate with the Russians. The fall of Idlib would be the end of the last rebel held province and  would open up the main highway through Syria from Jordan to Turkey.  Syrian Government troops are massing for an attack, Russian ships have  gathered off the coast at Tartous and the final phase of the Syrian war  looks imminent. There are 200 British and US instructors, doubtless with important  weaponry and intelligence, are trapped and the UK wants the Turks to  evacuate them to the Incirlik airbase In Turkey. This was apparently  refused.
Shields said that the company noticed an uptick in sales in the months leading up to the 2016 presidential election, and, again last year, amid fears of nuclear escalation with North Korea. Like Wise Company's former CEO Aaron Jackson, whom Bloomberg previously dubbed “America’s Survival Food King,” Shields said he likes to think of Wise’s products as “an insurance policy.”