Deploying mats underwater is nothing new; gabion mattresses or articulated concrete block mats are often used for stabilization. However, mats of a different type are being used in Lake Tahoe in an attempt to improve water quality.
Last week, divers placed rubber mats over half an acre of the lake bottom with the goal of smothering an invasive species. The Asian clam, researchers say, is causing excessive algae growth in the lake, changing the color of the water from blue to green in some places and altering the lake’s chemistry, possibly making it vulnerable to other invasives. The tiny clams—which are found as densely packed as 5,000 per square yard—are believed to have been brought in by boaters about eight years ago.
Another half-acre of mats will be added soon. The mats will be removed at the end of the summer and the lake monitored to see whether the clam population returns.