Thanks @papa-pepper! We will definitely use it. And your instincts on the water purification tables was correct. Here's a source: https://www.amazon.com/Taharmayim-Israeli-Water-Purification-Tablets/dp/B0077TB65U

and here's the verifying text:

One tablet purifies a whole liter of dirty stream/river/lake/well/pond water in just 30 minutes. May also be used to clean fruits and vegetables or disinfect wounds in emergencies