, coordinator for the UN's Global Wastewater Initiative
, previously told HuffPost
that in the event of flood, you might not know whether your water has been contaminated by sewage or chemicals. Most likely, however, it's been contaminated by both.
“When choosing water filters for flood emergencies, the simplest approach – a passive gravity feed system – is truly the best. Through this, filtration is enough to remove chemicals and most microbes," Zennaro said.
This gravity fed water system, like all gravity systems, requires no electricity or running water to work. It has a capacity over 2 gallons and uses the process of reverse osmosis, in addition to two carbon filters, to effectively filter out a number of impurities.
Zennaro added that if you know a flood might strike, it can be good to preemptively fill clean drinking containers with purified water in case you are unable to access your tap.