The Tahoe Divers Conservancy’s (TDC) greatest strength is centered on a grassroots, community-based focus, 
and it’s ability to advocate for the protection of Lake Tahoe and other marine environments of the Sierra Nevada. The marine environment is the most neglected ecosystems in the Sierra Nevada.
Most people may never experience the underwater world in marine environments but our divers play and work in marine environments all year around. Divers see first hand the garbage, pollution, and near-shore destruction.
The mission of the TDC is to document, study, investigate and conserve the complex marine environment that defines Lake Tahoe. Data collected by divers is utilized by numerous agencies in their planning efforts.
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Protect Lake Tahoe is about protecting all resources of Lake Tahoe; the environmental, historical and cultural resources of this spectacular region.
The Tahoe Divers Conservancy is working with divers of New Millennium Dive Expeditions on their current project to document the S.S. Tahoe which lies over 400 ft. beneath the surface of Lake Tahoe.
The steamer Tahoe was the longest and most beautiful ship ever to grace the waters of Lake Tahoe. The steamer Tahoe was commissioned by lumberman Duane L. Bliss, constructed in San Francisco in 1894, it was then disassembled and transported in sections by train and horse drawn wagons to the lakeshore at Glenbrook, Nevada. Under the Bliss family’s supervision the 169 foot steel-hulled steamship was reassembled and launched with great fanfare on June 24, 1896. The two wood-fired 
steam engines each drove a huge, three-bladed propeller and developed a combined total of 1200 horsepower.
Outfitted by period craftsman quality work, the steamer sported many polished brass fittings, a teak and mahogany trimmed deckhouse, and interior appointments which included leather upholstery, hand-woven carpeting, and marble lavatory fixtures. It also boasted some of the latest technological advancements of the day, including hot and cold running water in the lavatories, electric lights and bells, and steam heat. In addition to a dining room which could seat 30 people was a gentlemen’s smoking lounge.
The vessel was designed to accommodate 200 passengers in luxurious comfort as well as their baggage and other freight. She carried a crew of seven, including captain, purser, steward, fireman, engineer, and two deckhands. Beginning in 1901, following completion of the new Tahoe Tavern railroad pier in Tahoe City, the Tahoe departed from that pier every summer morning carrying passengers, mail and freight that had arrived by train. The steamer made a complete circuit of the lake stopping at all the major landings and returned to Tahoe City by late afternoon.
Following the loss of much of its
passenger traffic to the automobile as well as the loss of a lucrative federal mail contract in 1934,the steamer became too costly to operate and lay unused at dockside until 1940. Dismayed at the once proud steamship’s deteriorating condition, William S. Bliss, son of the original owner, bought the vessel back from the company he had sold it to, and ordered it to be scuttled as a memorial to the bygone era of steam traffic on the lake. The S.S. Tahoe went to the bottom of the lake off Glenbrook in the early morning hours of August 30, 1940. The present project by New Millennium Diver Expeditions will focus upon the completion of their work began back in 1999 on the shipwreck of the S.S. Tahoe. The Tahoe Divers Conservancy will help reinvigorate their efforts to complete their work on the Tahoe and bring back to the surface important historical and cultural documentation of this Maritime Icon that rests stoically 400 feet below the surface of her sapphire waters.
Visit the website at: www.nmde.org
Shifting Ecosystems
Under Lake Tahoe
When we are asked by tourists, “What do you see under there?” the most common response by divers with the Tahoe Divers Conservancy is “not much”.
Swimming among beautiful waves of granite boulders the size of houses, bright reflections of light from mica studded sandy lake bottom and a generally stark but surreal crystal environment.
We often describe diving in the Lake Tahoe as Zen Diving. In Tahoe we use diving as instrument of discovery, a mental discipline by which one attempts to get beyond the conditioned, “thinking” mind into a deeper state of relaxation or awareness. It is a psychophysical practice which leads to a greater focus and a more relaxed and peaceful frame of mind. 
But now the underwater world of Lake Tahoe is disturbingly full of strange, new life.
In just a few years, vast sandy nearshore that for centuries covered the bottom of Lake Tahoe have disappeared under a carpet of invasive plants.
The change is not merely cosmetic. Invasive species will upend the ecology of Lake Tahoe, shifting distribution of species and starving familiar fish of their usual food supply.
Eurasian watermilfoil, Curlyleaf Pondweed and the Asian Clam are all found in Lake Tahoe now.
And it is not just invasive plants. This summer scores of Brown Bullhead Catfish were found in Emerald Bay. Once confined to the Tahoe Keys and Taylor Marsh, non-native fish are propagating all over Lake Tahoe.
Asian Clam
Signs of the shift will be hard to ignore in the future. Mats of dead, smelly plants are already washing ashore on Lake Tahoe’s beaches, castoffs of a vast underwater expanse.
Multiple strains of E. coli bacteria and botulism spores will thrive in the new underwater garden, contributing to beach closings and the widespread deaths of migratory birds.
Fishermen will take notice that the lake trout, salmon and other fish will get skinnier each season.
Divers inputting milfoil survey data
How widely will the impact will be felt?
Will the lake will change faster than the researchers can study it?
Lake Tahoe may adapt as it has in the past, from mans intervention in the natural processes, such as logging and well meaning but destructive introductions of Lake Trout, crayfish and mysis shimp. But the invasive species are fueling change in the lakes at a rate far faster than we have ever seen.
Having dove and trained in the Great Lakes over the past decade and have witnessed the changes first hand, the Tahoe Divers Conservancy doesn’t necessarily know all the impacts, but we have seen enough to know that they are going to be catastrophic to the lake environment and to the regional tourist industry.
Is the ecological balance of Lake Tahoe at a tipping point?
And can it recover? Can we act quickly enough to help it recover?
None of the key species leading the change—like Eurasian Watermilfoil—are new arrivals. They were The zebra mussel famously invaded Lake Michigan two decades ago, and its cousin, the quagga mussel, wasn’t far behind.
But in the last two years the Eurasian Watermilfoil has taken off with alarming speed, exploding across the lake floor. Quickly followed by Curleyleaf Pondweed, 
which we only saw colonizing a season ago, spreading throughout the south-shore of Lake Tahoe growing to four feet in height.
And all this while the greatest threat to Lake Tahoe and the Western States are knocking on our door with the quaggas and zebra mussels which like to attach themselves to rocks and man-made structures, the quaggas can colonize sandy bottoms deeper in the lakes. Between them, the species filter lake water ceaselessly, making it so crystal clear that light can penetrate far deeper than before.
This change may allowed native species of algae to run rampant. In the Great Lakes algae species once relegated to shallow waters can now grow in 30 feet of water, twice as deep as a decade ago, and its waving tendrils cover vast offshore areas.
Together, these species can not only altered the clarity of the water but also devoured and filtered out the nutrients that used to sustain species at the base of the lake’s food chain, starving what larger fish are left.
Unfortunately, Lake Tahoe ceased to be a wholly native ecosystem long ago. Prior to large changes in the lake environment, Lake Tahoe’s aquatic ecosystem was relatively simple.
Beginning in the late 1800’s, species introductions combined with logging for mining started to alter the lake’s ecology.
Quagga trap set by Tahoe Divers Conservancy in 2007
The native food chain was dominated by a single predator, Lahontan cutthroat trout (Oncorhynchus mykiss) that fed primarily on pelagic tui chub (Siphateles bicolor pectinifer) and zooplankton. However, by 1939 cutthroat trout were extirpated from Lake Tahoe, and a large lake trout (Salvelinus namaycush) population replaced them as the top predator. Crayfish (Pacifastacus leniusculus) were introduced multiple times to Lake Tahoe and established by 1936. Found in large numbers (55 million in the late 1960’s and 65-75 million by early 2000.
After the introduction of Mysid shrimp in the 1960’s, again there was a shift in Lake Tahoe’s again the food web structure. After Mysis establishment the annual length and weight of returning spawners decreased. 
Finally, in the mid to late 1970’s and again in the late 1980’s, a variety of nonnative species were found in the nearshore environment. These warmwater fish introductions were illegal. Up to this point warmwater fish species were rarely found while native minnows remained abundant.
By the end of the 1980’s, largemouth bass (Micropterus salmoides) were common while redside shiner and speckled dace populations declined or were virtually eliminated from the Tahoe Keys.
The change in fish structure was substantiated by fishing guides operating out of the Tahoe Keys. Within a decade they could no longer collect minnows commonly used as bait during fishing charters on the lake.
Preliminary studies conducted at 16 sites around the lake by the University of Nevada- Reno and the UC Davis, Tahoe Environmental Research Center (TERC) in 1999, 2003, and 2006 demonstrate that 50% of these sites contain nonnative, warmwater fish species. 
Also, bass found in the nearshore often correlate with the presence of the nonnative plant species, water milfoil (Myriophylum spicatum) which produces favorable habitat for these fish.
What will the new aquatic order be?
The Great Lakes the food chain, as it was known, is gone.
“To be exact, a new food chain has settled”, said Brenda Moraska Lafrancois, aquatic ecologist in Minnesota with the National Park Service.
From 20 deep feet of water out to 40 feet or more, mussels cover the lake floor in a crunching layer as brittle as breakfast cereal. On their shells fronds of algae wave in the water, forming a carpet the lush green of a tropical forest.
In dives in the Great Lakes and specifically off the shores of Milwaukee, divers enter the shoreline stepping over razor sharp shells of the quagga mussels, slicing hard rubber reinforced booties. We saw families laying thick canvas tarps on the beach to picnic on, to spare the kids from the sharp shells. Swimming in tennies was the attire du jour.
We can’t fathom that scenario at Lake Tahoe.
To learn more about how we are working to PROTECT LAKE TAHOE click on the following link:
