Good idea about that sugar, Chaplain Gregory!
The article's main focus was preparation and assessing the conditions around the proposed baptism area. Since Jesus was baptized in the Jordan after John the Baptist had already baptized many people, we can assume that any hazards had previously been removed.
When it comes to water-born disease or crocodiles, etc., I suppose if those things are known to be a hazard in the area, another venue might be chosen if available. I remember baptisms in Ethiopia taking place in a pit that was dug in the red earth, and the Ethiopians were baptized in white robes that turned red when they came up out of the red water. Perhaps it was during the dry season when the rivers were down to a trickle, I don't know. There was no baptistry ready for use at that time.
I know of some who believe that since baptism is blessed by God, "there should no evil befall you" while you are being baptized, and therefore one shouldn't worry. What do you think about that?