Lake Tahoe clarity increases 6.4 feet
By Kathryn Reed
For the second year in a row the water in Lake Tahoe is clearer than the preceding year.
As noted last year by the UC Davis scientists who take the measurements, the lake’s clarity has been stable for the last decade. Still, the last time the white dinner plate looking Secchi dish could be seen more than 70 feet below the surface was in 2007.
The Secchi disc is ready to be used to test Tahoe’s clarity. Photo/LTN
The 2012 reading of 75.3 feet is a 6.4-foot improvement from 2011. The disc is dropped over the side of a boat and eyeballed by the scientists on deck. Twenty-two readings are taken throughout the year to come up with the average clarity figure. In 2012, 107 feet was the best reading and 57 feet the worst.
“We are very excited about the results from 2012, especially within the context of the long-term record for annual and winter clarity,” John Reuter, associate director of the UC Davis Tahoe Environmental Research Center, said in a statement. “It is particularly encouraging to see clarity improve during wet years when the amount of fine sediments and nutrients going into the lake is high.”
In the world of science a trend is established at about the five-year mark, according to Kristi Boosman with the Tahoe Regional Planning Agency.
- Lake Tahoe clarity readings
- • 2012: 75.3 feet
• 2011: 68.9 feet
• 2010: 64.4 feet
• 2009: 68.1 feet
• 2008: 69.6 feet
• 2007: 70.1 feet
• 2006: 67.7 feet
• 2005: 72.4 feet
• 2004: 73.6 feet
• 2003: 71 feet
• 2002: 78 feet
• 2001: 73.6 feet
• 2000: 67.3 feet
— Source: UC Davis
A concerted effort has been under way since 1997, when then President Bill Clinton visited Lake Tahoe for the first environmental summit, to restore the lake’s clarity. That summit led to the environmental improvement program being created and the Lake Tahoe Restoration Act providing money for the program. In the past 15 years more than $1 billion has been spent on various projects in the basin with the primary focus of reducing sediment that clouds the waters of Tahoe.
While monitoring is in place at many of the projects to test what is reaching the lake, it is not possible at this time to point to one thing that is responsible for the improvements.
Researchers say they need more data on stormwater to make more definitive conclusions about why the numbers are changing. Another troubling thing to scientists is the summer clarity numbers continue to decline and they don’t know why.
The Secchi disc has been used since 1968, when the apparatus could be seen to an average depth of 102.4 feet.
That’s great but means nothing if you are standing on the shoreline, algae, algae and more algae.
no rain,no snow,no weather!
Even tea gets clear if you let it sit!
How deep did the lake mix??? Anyone….
I would suspect that right now the Lake is VERY Clear.
It is nice to know that its not getting worse This decade.
Although additional resources have been available since 1997, serious efforts to restore the then rapidly declining clarity have been going on since the 1970s.
If you make $29,000 a year, and don’t spend a single penny of it, it will take you 34,482 years to save a billion dollars .
At this point I’m most concerned about water level. When the snow doesn’t come the water drops. Two years of drought can threaten our launch ramps around the lake. Anyone around in the 90’s must remember how bad it got then. If we could slow down the release of water from the dam in Tahoe City, we could reduce the impact of drought years. What has happened is that down stream water rights are granted to people on the Truckee River. So a federal court has ruled that the dam in Tahoe City must release water in drought years. I don’t think this is justified because if the dam was never built, a drought year would result in little or no water flowing out of Lake Tahoe. We should be allowed to reduce the flow of water during drought years. This would allow some water flowing out of the lake, but not so much that the lake drops so fast. To understand my point, you need to understand what would happen without the dam. We need the dam to help regulate the water. But we also need to hold back more water during drought years. The people down stream should not be entitled to the same large amount of water during drought years. We need that water so that our launch ramps remain open. I think we need to go back to court and address drought years more fairly. Of course three or four drought years will close launch ramps. But if the water was regulated fairly we could keep all of launch ramps open during two drought years. We may be facing this situation again soon.
I remember a few years when the Truckee flooded hwy 89 and many many other points east.
This clear weather does suck for Skiers. But its awful Purdy right now.
AND we all know it could dump 10 or 20 FEET of snow in a matter of a couple weeks. Fat Skis waxed and waiting!!
Mid March, April? May?
It will come
Right now I think you just have to make lemonade out of
Lemons?
I just I am sayin, It not time to freak out just yet
tahoe Pizza eater,
Yes I do remember those drought years of the 90’s. The lake was so low off El Dorado beach you could walk out to the shelf and be fishin’ in the deep blue with a short cast.
I agree we need to retain more water in Tahoe during drought years.I know the people down stream would raise a ruckus but I believe we could come to a reasonable compromise with the powers that be, or at least I hope we could.
Many years ago down at Bridgeport reservoir the ranchers down stream demanded that the water gates be opened at the dam for their pastures. The ranchers had water rights and wanted “their” water. They all have well water but this was an old agreement that they still enforce.
Opening day of trout season for Calif. be damned they said. Low water in the reservoir? You bet, big time. They dang near drained the place. Boat ramp closed to many that didn’t have a 4-wd to back up your boat waay out there to launch.
Opening day is a big money maker for the little town of Bridgeport. They suffered a big blow to their economy that year as many fishermen just turned around and went back home.
The water wars have been going on for a long time and will just get more intense with time.
I’m glad to see a bit of clarity has returned to the lake, hope it’s an ongoing trend. Old Long Skiis