Yes, the thread was split out of an old thread that was discussing correct water temps for boas for swimming.
The only time I've seen boas soak is either when there are mites or when they are trying to cool off from too hot of a cage. Not saying some don't or won't here or there but I have never had a boa soak before that didn't have mites.
One other thing - does she have a hide? It could be the bowl is the 'safest' feeling spot but the first thing I would do is check for mites.
Hope it's not the case!
good luck