Did you know … Scientists have been measuring Tahoe water clarity since 1968? | SierraSun.com
YOUR AD HERE »

Did you know … Scientists have been measuring Tahoe water clarity since 1968?

Sierra Sun file photo
ALL |

Scientists have been measuring Tahoe water clarity by lowering a 10-inch white disk into the lake since 1968.

Called a Secchi depth test, researchers record the maximum depth before the disk disappears from view.

Annually, scientists take about 25 readings throughout the year.



While researchers have observed increasing clarity in some years, on average visibility has been dropping by one foot per year since the 1960s.

Depths of over 120 feet were recorded in the early years, but in 2006, visibility had dropped to an average 67.7 feet, a reduction of 4.6 feet from the year before.



Tahoe’s low point for clarity so far came in 1997 at 64 feet.

Years with high runoff wash larger amounts of material detrimental to lake clarity, predominantly nutrients and fine sediments, into Lake Tahoe.


Support Local Journalism

 

Support Local Journalism

Readers around Lake Tahoe, Truckee, and beyond make the Sierra Sun's work possible. Your financial contribution supports our efforts to deliver quality, locally relevant journalism.

Now more than ever, your support is critical to help us keep our community informed about the evolving coronavirus pandemic and the impact it is having locally. Every contribution, however large or small, will make a difference.

Your donation will help us continue to cover COVID-19 and our other vital local news.

For tax deductible donations, click here.

Start a dialogue, stay on topic and be civil.
If you don't follow the rules, your comment may be deleted.

User Legend: iconModerator iconTrusted User