Sometimes what seems to be a good idea can wind up being terrible in hindsight.

Take, for example, an effort in the 1970s to create an artificial reef off Fort Lauderdale, Florida using old tires. It would have been great if the tires, 700,000 of which were sunk in bundles, hadn’t broken apart over a 35-acre/14 hectare area and settled on existing reefs and eventually killing parts of those reefs.

To remedy that, so far divers have removed about 130,000 of those tires over the past nine years, with an additional 30,000 expected to be hauled up by this coming autumn. After that, the Florida state government will be looking for contractors to continue removing a chunk of the remaining tires, according to the Florida Sun-Sentinel.

Industrial Divers Corp. is the company currently under contract to get rid of the tires. Company Vice President Rocco Galletta told the newspaper:

“What we’re doing is removing the tires that are the biggest threat to the reef, which are the most mobile ones. There’s still plenty out there, stacked two or three or four on top of each other and very loose. There are no corals growing on them. Marine organisms will grow on tires. The issue is the tires that move, and once they move, those organisms are not going to do well on an unstable surface.”

For more info, check out the Sun-Sentinel article here.