People who have pools are used to adding several inches of water every few weeks to keep the pool water level constant. In the peak of summer, you can lose over 1/4″ of water to evaporation daily. Does the same logic apply to backyard ice rinks in the winter? Does the water in my rink evaporate? What happened to my ice rink water level?
While working towards my engineering masters degree at the University of Illinois, I had coursework focused on thermodynamics, fluid mechanics, and heat transfer. The underlying science to what I am about to share, with respect to backyard rinks, is founded in that subject matter. I promise to keep this simple and hopefully, my advice can help you prevent water loss for your rink this upcoming season.
Natural water loss due to evaporation does occur in the winter, but it is minimal compared to the summer months. In Chicago or Toronto, for example, winter evaporation averages less than 0.03 inches per day. Let’s put that in perspective. It will take standing water 10 days to lose a bit more than ¼”. That is quite significant when you consider that rinks may have as little as 3” inches of water. The good news is that when that the top layer of water becomes ice, the ice acts as a lid and helps prevent evaporation. The water underneath your ice is like water in a closed jar. It has no way out for evaporation. Furthermore, there is also a very rare circumstance of air temperature and pressure where ice skips the water phase and jumps directly to vapor. This process is called sublimation. Sublimation is a near non-factor for ice volume loss. The moral of this story is very simple. PRACTICE PATIENCE! Wait until it is cold enough outside for water to freeze before you fill your rink!
Once your rink is filled and you have ice, you are likely doing regular maintenance to your rink. With maintenance/resurfacing you are likely gaining water, not losing it. If you consider a 30′ by 50′ rink, a 30 gallon coating with the Iron Sleek Resurfacer or just 6 minutes evenly sprinkled from your hose will more than make up for 0.03 of an inch loss. Basic rink maintenance is enough to keep your water levels from dropping.
Here is the truth about your water level problem. It’s not evaporation! You probably have some small leaks around your rink. Small leaks are not necessarily the end of your season or the end of your backyard rink. They are simply a nuisance and a frustration which equate to more maintenance and more work to keep healthy ice. When it comes to small leaks in liners, the best intervention is prevention. Take your time before putting out your liner or tarp to make sure that you have removed all of the stones and pointy twigs from your rink. Check your rink boards thoroughly to insure there is nothing pointy that could contribute to small leaks by creating tiny holes.
The most common place where people forget to protect their liner is at the board bottom where the liner, the land, and the board meet. Since the board edges can be especially sharp, you should mound some topsoil or sand against the bottom corners to protect the liner. Iron Sleek offers Ice Rink Base Cove, which is designed to protect your liner from the bottom, where the water pressure is the highest and the boards are sharpest. The base cove will also prevent the liner from ballooning under the boards. Base cove fully replaces the “mounding” exercise and better protects your rink. Take it from the pool industry professionals who use wedge shaped foam at the pool bases for even the toughest of liners at 25 mil. Even if the board looks snug onto the grass, people will still run into the boards, pucks will be blasted and heavy adults will sit on the rink boards; the boards will move. Prevent leaks by a thorough inspection of your land, inspection of your sideboards, and by taking the proper measures with your board bottoms with either sand, top soil, or the innovative Iron Sleek Ice Rink Base Cove.
The mystery is solved! Why am I losing water? It is not evaporation or sublimation. You have leaks. The best way to fix tiny leaks is to avoid them. Consider taking some of the measures described to prevent liner leaks. Good luck and let’s hope for a cold winter.
See you on the backyard ice!