How do we protect our interlock driveway from water damage?
During this summer, we have installed interlock in our driveway and on the walkway. We have also created garden beds with interlock walls. One of my concern is that we live in the country and the water in our area contains sulfur and also iron. We use a softner system for our in-house water. However this is not the case for the water used outside. We were informed that the water can damage our interlock by turning it white and we have noticed that it's definitely the case by looking at some of our neighbor's interlock. I would like to know if there is a way to protect our interlock and our big investment from getting damaged by the water? Please note that we have a sprinkler system to water our lawn and that it has been set up already to minimize the contact of water with our interlock. However, the water is still touching our interlock in some areas, especially in the interlock walls of the garden beds.
There are three approaches that you can take, none of which is ideal. Only you can decide which is the lesser of three evils. You can soften the water for an exterior use. This eliminate the minerals and the problem, but it increases your operating costs and trace elements of salt in the water is not great for your plants. You can periodically acid wash the interlock with mild hydrochloric acid. This will remove the mineral deposits, but again not very good for your foliage. You can seal the interlock with a sealer to prevent moisture absorption, but despite claims of long life, I suspect you'll be sealing it on an annual basis or semiannual basis.