Secchi Records
While the idea is to get accurate Secchi depth readings, not try to break records, the Secchi disk lends itself to claims of being the record maximum (or minimum depth). We welcome other Secchi records as well. We accept claims with some evidence of documentation; "official" records must be from a published article. Submit any claims to rcarlson@kent.edu
Theoretical Maximum Secchi Depth
If you could lower a Secchi disk into absolutely pure water, the theoretical maximum value would be between 70-80 meters (230-262 ft).
Deepest Recorded Secchi Depth
80 meters on October 13, 1986 in the Weddell Sea, near Antarctica (W.W.C. Gieskes, C. Veth, A. Woehr-mann, and M.Graefe, EOS, 1987). Citation courtesy of Hendrik Buiteveld
"about 70 meters:" is reported in the Sargasso Sea, using a 1.2 m disk. Mahon Kelly, (Personal Communication)
66 meters (217 feet) in the Sargasso Sea (Taber and Dubach, 1972)
53 m (174 ft) in the eastern Mediterranean (Berman et al. (1985)
44 m (144 ft) was obtained in Crater Lake, Oregon, using a 1 m diameter disk. Larson (1972) At the same time, Doug recorded 39 meters (128 ft) with a 20 cm disk.
33 m (108 ft), Lake Tahoe, John LaConte using 9.5 inch (24 cm) dinner plate in 1873
Smallest Secchi Depth
1-2 cm (0.4-0.8 in) in Spirit Lake, Washington, after the eruption of Mt. St Helens (Doug Larson, Personal Communication). The water of the lake was colored black by the decaying trees in the lake.
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Disk disappearing under an algal scum in Crystal Lake, Ohio |
3-5 cm (1.2-2 in) in "puddles" in Kenya (Orlando Sarnelle, Personal Communication)
8 cm in a Nebraska reservoir made turbid by suspended silts and clays (Chris Holdren, Personal Communication).
10 cm in aquaculture pond, Delaware State University by R. Carlson (Personal Communication). The chlorophyll concentration was 558 ug/L (J. Shalles, Personal Communication).
Perhaps the strangest unofficial record for shallow Secchi depths should be given to Bob Kortmann (Personal communication), who, lowering his disk through foam generated by a blue-green die-off, reported a Secchi depth of minus 5 inches; the disk disappeared before ever reaching the water!
Smallest Secchi Disk
2 cm used by R. Carlson to measure strength of coffee
2.5 to 5 cm used in small puddles (Richard Hill, Personal communication).
10 cm by E. A. Birge and C. Juday, in Lake Mendota, Wisconsin in the fall of 1900 (Hutchinson, 1957; Lathrop, 1992).
Largest Secchi Disk
1.2 m (Mahon Kelly, (personal communication)
Most Secchi Depth Readings in a Day by an Individual
532 measurements in a single day by a single volunteer by Gerrit Vershuur (Vershuur, 1997)
Most Secchi Depth Readings in a Year by an Individual
3,510 readings (October, 1994-August, 1995) Garner Lake, Tennessee by Gerrit Vershuur (Vershuur, 1997)
Most Sites Sampled by a Single Individual
1,007 lakes in a single county (Itasca County, MN) by Mary Shideler, MN Citizens Lake Monitoring Program volunteer
Mary Schideler,
Not known Literature Cited Berman, T., P.D. Walline, A. Schneller, J.
Rothenberg, and D.W. Townsend. 1985. Secchi disk depth record: a claim for
the eastern Mediterranean. Limnol. Oceanogr. 30: 447-448. Gieskes, W.W.C., C. Veth, A. Woehrmann,
and M.Graefe 1987. Secchi disc visibility world record Shattered. EOS,
Transactions, American Geophysical Union. 68:123. Hutchinson, G.E. 1957. A Treatise on
Limnology. Vol. 1. Geography, Physics, and Chemistry. John Wiley & Sons. Lathrop, R.C. 1992. Nutrient loadings,
lake nutrients, and water clarity. In: J.F. Larson, D.W. 1972. Temperature, transparency, and phytoplankton productivity
in Crater Lake, Oregon. Limnol. Oceanogr. 17: 410-417.
Le
Conte, J. 1883. Physical studies of Lake Tahoe. Part 1. Overland Monthly 2: 506-516. Taber, R.W. and H.W. Dubach. 1972. 1001 Questions Answered about the Oceans and Oceanography. Dodd, Mead. Vershuur, G.L. 1997. Transparency
relationships in Garner Lake, Tennessee: the relationship between Secchi depth
and solar altitude and a suggestion for normalization of Secchi depth data.
Journal of Lake and Reservoir Management. 13(2):142-153. Return to the Secchi Disk Page For more information on The Secchi
Dip-In, contact us at: rcarlson@kent.edu or write
The Kayak Lady, sampled
1,007 lakes(htttp://marythekayaklady.com)
Kitchell. Food web management: A case study of Lake Mendota . Springer-Verlag
1091 Munroe Falls Kent Road
Kent OH 44240