Discussion»Questions»Environment» If over a period of time I overwater my lawn or garden, am I inviting the possibility of creating a sinkhole under my property? ~
I don't think so. The ground water works to dissolve certain types of rock below the surface which allows the sinking to happen. You watering the surface doesn't play into it, as far as I have ever known or read. They are pretty common here in Florida. We are only eight feet above sea level.
Have you read something to suggest surface watering can cause sinkholes?
This post was edited by Thriftymaid at July 22, 2017 11:42 PM MDT
You would have to pour a huge amount of water onto the land for a very long time to have any effect.
I can amplify what Thriftymaid has written.
The "certain type of rock" she mentions there is limestone or chalk, possibly gypsum; and these are very slowly soluble in fresh water. In Florida it is limestone; and the altitude there is not the governing factor.
Over tens or hundreds of thousands of years water percolating through the limestone's natural joints (tension-cracks), bedding-planes (the discontinuities between each layer of rock) and faults slowly dissolves it away, creating subterranean conduits - caves if large enough for humans to explore.
The process does need the "hard" water to escape, and it does, through springs, so fresh, soft water from rain or snow-melt can recharge the conduits to continue the dissolution. Eventually various spots in the rock's structure are weakened enough for them to collapse, usually with a helping hand such as flooding or a minor earthquake. Obviously added weight such as a house on the weak spot will risk earlier failure.
You may have heard of the "Blue Holes" in the Bahamas, and similar features in Florida - these very deep springs are entrances to the flooded caves below; often well below sea-level because the caves developed particularly well when sea-level was much lower, during the present Ice Age's last one or two glacial spells.
So continue to water the lawn, but don't over-water it. That only wastes water and may damage your plants!
