Water in the Bilge

My strange luck...I have a much bigger problem with water in the bilge when the boat is on the hard than I do when we are sailing! This is an especially pesky problem up north here because of the water then freezing in the bilge. This itself is a puzzle to me as I do fill the bilge with a gallon or two of anti-freeze. The water that gets in seems to freeze on top of this anti-freeze. As you can see in the photo below there is about 2 inches of very hard ice on top of this anti-freeze that I had to chip out with hammer and screwdriver. What good is antifreeze if it is just going to sit under the water and not freeze itself but allow a hard freeze above it?

At any rate we now believe that water gets in through the stern locker. The only thing big enough to catch the amount if water we find in the bilge is the cockpit which we had not covered. Water that drains aft on the seats should enter the channel around the stern locker and then drain forward to the cockpit floor and down the scuppers. I think the boat is sitting with a lean that is too far aft so that the water actually goes up and over the channel and into the locker itself. From there it can go around the vent hose and find its way into the bilge. So a better tent type cover for the cockpit was in order. We used 1" pvc pipe, duct tape, and blue tarp to put a complete dome over the cockpit. Hopefully, this will keep the water out! We'll go up and check again after the next hard rain.