Question
We have an antique stone fountain that leaks at a rate of 3 gal a day.  I have caulked around all the fittings, used "stop a leak" which has slowed the leak at times, and see no evidence of water external to the fountain.  Any ideas how to find the leak and fix it or is there anything I can use to seal the inside of the fountain to slow or stop the leak.  Thank you.  Curt

Answer
First you need to identify the location of the leak. You can do this by eliminating the possibilities. Start by turning the fountain off and filling all reservoirs full to the brim. Mark each reservoir with chalk at the water line.
Let the fountain sit for a day or two and note the changes in water level in each reservoir. If the fountain level does not change significantly in any reservoirs then your leak is in the plumbing or in the movement and splashing of the water. Some active small fountains in hot dry climates easily loose this much water simply from evaporation and small amounts of splash that quickly evaporates on the ground. If one or two reservoirs/areas/levels hold water and another does not then you should be able to start to narrow down the possible sources. A big possibility is that the stone has simply become very porous and is absorbing the water. This causes it to evaporate all around the fountain so there is no obvious spot showing the leak.  You can fix this by cleaning and scrubbing the fountain and then letting it dry completely (LIKE FOR A WEEK). Once VERY dry and clean you can seal the stone on all sides with a transparent masonry sealant that penetrates the surface of the stone. If the stone is not completely dry it may cause the sealant to become milky and not stick, destroying the look of your piece. Make sure you get a sealant that is rated for full immersion and do a test area on a part of the fountain less seen to be sure you like how it will look after it dries, as sealants often darken the colors.
Other suggestions are using plumbers putty between pieces of the fountain and checking your plumbing under pressure by capping the end of the system with a valve and closing it down to see if there are any joints leaking.
Anyway, fountains can be a real pain in the neck...so good luck.


Sean J Murphy, LA,ISA, LEED AP
Please check out my blogs and articles on landscape topics like this on my websites.
http://www.seanjmurphy.com
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