Dr. Ladner was invited to present to a community and church group on water purification and treatment. This will be held at the Church of Jesus Christ of Latter-day Saints, 200 Hayworth Dr., Simpsonville, SC, on Saturday, August 24th. All of the materials will be uploaded to this blog post by the date of the event.
For starters, here is a Google Map of Environmental Engineering locations. Several of the sites indicated on the map are drinking water treatment plants. Satellite views of those sites will be used to show how water is purified on the municipal scale. That knowledge helps us understand how we can purify our own water on a small scale.
Water Purification
We’ll do a demonstration of coagulation and flocculation, similar to this video:
We’ll also have a demonstration of reverse osmosis (RO) similar to this video:
We’ll talk a lot about size of water contaminants. This poster is useful for helping to understand the size of various things that could be in water.
- A water molecule is about 0.3 nanometers. (Another size term is “Daltons”. Water is 18 Daltons).
- A sodium ion is about 1 nanometer, or 23 Daltons. (But sodium attracts a lot of water in a “shell” around it, so it behaves like something bigger).
- Caramel color has molecules probably about 130 Daltons. (It’s harder to find info on the nanometer size, but probably a few nanometers).
- Fructose is about 180 Daltons.
- Viruses (like adenovirus, a common water-borne pathogen) are 70 to 100 nanometers.
- Bacteria are about 2 microns, or 2,000 nanometers; bigger than the whole poster! Clay particles can be about that size, too.
- Cryptosporidium are about 4 to 6 microns, or 4,000 to 6,000 nanometers.
- Giardia are about 8 to 21 microns, or 8,000 to 21,000 nanometers.
Water Storage
The Center for Disease Control website has concise, useful information: https://www.cdc.gov/healthywater/emergency/creating-storing-emergency-water-supply.html#print
Here is a PDF of that page, with some highlights and notes: https://cecas.clemson.edu/ladnergroup/blog/wp-content/uploads/2024/08/Storing-Water-CDC.pdf
Cases of bottled water can be a good method. CDC recommends one gallon of water per person per day. Since a gallon is 128 ounces, and a typical water bottle size is 16.9 ounces, that’s 7 water bottles per day. It’s recommended the minimum storage amount last three days. That’s 21 water bottles per person, or almost one case of 24.
For a family of five, that’s five cases of water. Seems doable!
Now then, if we want more security, we could store enough for a two-week period. That would be 70 gallons for a family of five, or 22 cases of water. Round that up to 24 cases. Then, if I use one case per month in normal activities (leave in the car for outings, etc.) I’ll rotate through my water storage in two years. And two years is the typical expiration date for store-bought bottled water!