Because of the geographical/geological circumstances where lighthouses are located, the use of wells for drinking water is usually out of the question, and rainwater is collected from the roof of the keepers dwelling and stored in cisterns.
I pointed out to a guide at the Currituck Beach light that the rooftop was liberally covered by guano, and I commented aloud that I suppose they let the rain wash the roof before allowing the water to enter the cistern. The reply to that was NO... there is no provision, valve or similar, to divert the rainwater. All rainwater goes to the cistern, and any excess just overflows from the cistern.
I then asked what did they do to prevent bird feces vectored bacteria (virus) from causing illness through the drinking water.
The reply was, they put lime into the cistern to purify the water.
My questions to the Harbour Lights community who deal in real lighthouses are:
a. Is this true?
b. Did it work? Does lime really kill the bacteria/virus?
c. If lime can kill the nastys, would it take a concentration that might itself be harmful to those who drink
the lime laden liquid?
