Cleetwood Cove Trail
Cleetwood Cove Trail is one of the only trails that leads directly to the water. Believe it or not, the water in Crater Lake is cleaner than the water that pours from your faucet at home. That’s because roughly 83% of it comes from rain and snow falling directly on the lake’s surface. (The rest is runoff from precipitation landing on the slopes inside the caldera.) No rivers or creeks carry silt, sediment, or pollution into Crater Lake. The other reason the lake is so pure is that its volcanic basin is currently dormant. The last eruption here occurred some 4,900 years ago. Since then, activity has ceased. Dissolved gases and minerals enter the lake through hydrothermal vents on the lake’s floor, but in very small amounts. With so few particles suspended in the water, Crater Lake is exceptionally clear: certainly one of the clearest lakes in the world. When an 8-inch (20-cm) Secchi disk is lowered into the water, the average depth at which it disappears is nearly 102 feet (31 meters)!
On average, they find that 1% of the sun’s visible rays persist to a depth of 330 feet (100 meters).Even at 1% of the sun’s visible rays are more than enough to support the survival of aquatic plants. Moss, for example, hangs from underwater cliffs as deep as 460 feet (140 meters) below the surface. Nowhere else in the world has moss been found thriving at such tremendous depths.
The ultraviolet (UV) part of the spectrum also pierces deep into Crater Lake. In fact, in 2003 scientists were amazed to discover that UV rays penetrate deeper in Crater Lake than was believed to be theoretically possible in even the purest of water. A benchmark of physics had to be reset!
Crater Lake is becoming important to scientists as a barometer with which to measure changes happening on a regional and global scale, such as changes in climate and atmospheric pollution.
