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Lake Tahoe Restoration Underway By Will Hart LAKE TAHOE, California, October 5, 2002 (ENS) - Not that long ago Lake Tahoe looked like the quintessential alpine lake; a pristine jewel set in a thick blanket of green forested mountains. But looks proved deceiving. The forest was hiding a vulnerable side that would soon be revealed when a seven year drought struck from 1988 to 1994. Fir trees began dying in increasing numbers every year. As the forest habitat quickly unraveled due to a drought triggered bark beetle infestation, history began to catch up to Tahoe and the tarnishes became more apparent.
Limnologist Charles Goldman, who had been studying the lake's clarity since the late 1950s, reported that Tahoe had been losing about a foot of clarity a year since the late 1960s. At 99.99 percent purity, Lake Tahoe is one the purest, clearest lakes in the world. It is famous for its sky blue waters and they are one of features that attract four million visitors to the lake every year. In the 1950s a white plate was visible to a depth of about 115 feet; today that same plate is only visible to about 70 feet. According to Goldman the problem is the growth and spread of alga, a natural aging process called "eutrophication" that eventually turns every lake into a pea soup green color. But this natural process was being speeded up by human activity. "We may only have about 10 years to arrest the problem. If we don't the lake will become murky in about 30 years," Goldman says. It was in the 1950s that a real estate and commercial development boom exploded. These were the so called bad old days before environmental awareness had dawned and impact reports were not required. One of the worst ecological disasters was engineered at the Tahoe Keys development. Developers decided that turning the lake's largest wetlands into a housing tract and marina would be a very lucrative and grand idea. A vast wetlands spread out across the southwest corner of the lake. It covered thousands of acres and acted like a huge natural filter. This was the most important wetlands ecosystem in the Tahoe Basin.
Developers dredged right into the heart of it as they created a housing tract giving each homeowner his own personal backyard dock. In the process the relatively shallow meandering stream that had emptied into the wetlands was changed into a deep, straight ditch. Human engineering completely undid the threads of the natural tapestry. The wetlands had been a crucial piece of the vastly complex and amazingly diverse Tahoe ecosystem. The shallow, slow flowing stream overflowed during spring runoff. The overflow created a marsh that attracted waterfowl and many other wildlife species. The water became trapped in the marsh and the sediments and nutrients it carried were slowly filtered into the soil. The ditch that replaced this natural system was fast flowing and deep and its nutrient rich and sediment filled waters were dumped right into the lake. From the 1950s to the 1980s about 75 percent of Lake Tahoe's natural wetlands were destroyed. Nutrients also entered the lake as a result of poor road drainage, erosion and from golf courses and other developments. Ten years ago the lake seemed to be going to hell in hand-basket. But things changed on a dime.
The public, business owners and government officials finally reached a critical turning point when they realized that for Lake Tahoe to have a healthy economy it must have a healthy ecology. In the past decade a number of important corrective programs have been initiated. Under the inspiration of the Tahoe Restoration Act a consortium of 50 public and private agencies are in the process of implementing the Environmental Improvement Plan, a 500 project capital improvement program that is estimated to have a total cost of $1.5 billion. Streams have already been restored, road banks stabilized, the highway improved and parts of the forest thinned of tangled undergrowth and sickly trees. This past summer a group of scientists from China came to the lake to study the restoration program. Saving the environment is often a matter of local grassroots activism spawning a broader awareness that can be turned into a regional or even a national campaign. Copyright Environment News Service (ENS) 2002. All rights reserved. |
Lake Tahoe (Photo courtesy 
Tahoe Keys development (Photo courtesy 
Emerald Bay, Lake Tahoe (Photo courtesy 