If you use a pool cover over the winter, you likely watch it fill up with water and snow as the season goes by. You should take care to drain this water off the cover once in a while. Of course, there are countless ways to drain the water, such as using a garden hose, a sump pump, and bucketing it out to name a few.
Chances are you have come here because you have googled how to drain the water off the pool cover. As a result, you likely have come across something like this:
These pool cover pumps/drains work well enough. They drain is filled with sand to keep them weighted down and they have enough surface area to prevent them from getting clogged easily by debris, such as leaves. Even so, they have a critical flaw in my opinion. Typically you might be inclined to use these over the winter. They can take a while to drain a pool cover and if the temperature is fluctuating between freezing and not, then of course they may stop working. More significantly though is that the hand pump itself is rather brittle and they don’t fair well in the cold weather. Also, I believe the sun takes a beating on the plastic they are made with. In short, unless you are watching the weather more carefully and packing yours up each and every time you use it, then you may have them fail on your as well. I have had two of this style of drain fail on me due to the hand pump.
As a result, I opted to find an alternative solution. At first, I found a siphon with a rubber pump (ie, aquarium pump), like this:
The problem with this style of pump was that the diameter of the tube was too narrow at 0.31 inches. It drains entirely too slow and the hose is too wound up in circles. As a result, it freezes even more easily.
Lastly, I stumbled upon a shaker siphon pump. This is almost perfect. It comes in a 10 foot option, 1/2″ diameter hose and is honestly easier to operate than the hand pump. All you have to do is get a fair amount of the hose under water and shake it about until it completes the siphon.
I admit this siphon is not perfect either though, as it needs weighed down in the water to keep it from curling back out. I simply used the weighted filter from the first pool cover pump. I estimate I was able to drain hundreds of gallons of water off my pool cover in less than a day.
pool cover full of water 
pool cover drained of water with shaker siphon pump
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