Many SW Florida pool services will get the age-old question today “Is my pool going to overflow in this heavy rain?” ? Your pool probably would have overflowed a LONG time ago if that was possible or likely to happen.
More importantly, know where your overflow is or where it runs to. That area will have to usually have to flood before your lanai does. Actually, one of your concerns could be that your pool will actually drain! This isn’t very likely either, but if the overflow is in an area that will flood, it could cause a siphon, based on the relative levels of both the pool and the end of the overflow line! This is why we always recommend drilling a ventilation hole in the overflow line, if you are in a situation where there is a significant possibility of that happening. If there is a break between one end of the line and the other, it will prevent the vacuum from ocurring.
There are numerous methods by which your pool could be fitted with an overflow to drain excess water. Most will fit one of two categories:
1: a grate in the waterline tile that leads to a pvc line, running into the ground and out into the yard.
2: a line running from either a vacant fixture in the pool wall or somewhere in the skimmer (often the second hole in the bottom that does not provide suction). This will often lead a 90 degree fitting somewhere outside the lanai, cage or yard.