Lake Tahoe Historic Secchi depth

Historic Secchi depth (Water clarity) measurement of Lake Tahoe, CA/NV. There are two sampling stations Index (LTP, 39.0972 -120.155) and Mid-lake (MLTP, 39.1417 -120.0153 ). Observation at Index station started on 1967-07-28, and averaged sampling interval is around 14 days. Mid-lake station sampling has been started on 1980-04-29, and taken at approximately 33 days interval. See methods for details.