The hydrophones at Lime Kiln State Park are located just southwest of the Lighthouse in about 7 meters of water. The two hydrophones were attached to moorings by scuba divers. There is a long history of hydrophone deployments, repairs (after winter storm damage), and acoustic research at the Lighthouse.
The current two hydrophone system began streaming live sound through a computer in 2007. Dr. Val Veirs wrote custom software for the computer which automatically detects unusual sounds (like orcas) and measures the average sound levels for the area.