SELF-HELP MONITORING

— A WISCONSIN LAKE —

SELF-HELP MONITORING

— A WISCONSIN LAKE —

Mary Jane BumbyGreen Lake

Green Lake CountyWisconsin

Graph of Secchi & Temperature Readings

Graph of Secchi & Temperature Readings

2002 pier thick with aquatic plants! No swimming here!2002 pier thick with aquatic plants! No swimming here!

Mats of Oscillatoria sp.Mats of Oscillatoria sp.

Map:East & West Deep-waterMap:East & West Deep-water

Monitoring EquipmentMonitoring Equipment

Collecting Sample of Plankton after 17 Ft. vertical pull.

Collecting Sample of Plankton after 17 Ft. vertical pull.

Some Green Lake Plankton Deep-Water

Some Green Lake Plankton Deep-Water

2004 Monitoring Record Sheet and Data Collected

June 3

2004 Monitoring Record Sheet and Data Collected

June 3

G L Subwatershed AcreageG L Subwatershed Acreage

1992 Map of Watershed1992 Map of Watershed

1980-2003 Secchi Ave 1980-2003 Secchi Ave

SAME SECCHI “SMOOTHED” SAME SECCHI “SMOOTHED”

EAST & WEST MIN & MAXEAST & WEST MIN & MAX

RAINFALL MAY - OCT(MONITORING DATES)RAINFALL MAY - OCT(MONITORING DATES)

CLOSE TO LAKE SURFACE: SECCHI AT 1/2 M (2 FT) &

1/2 SECCHI READING

CLOSE TO LAKE SURFACE: SECCHI AT 1/2 M (2 FT) &

1/2 SECCHI READING

2003 WEST DEEP-WATERSTATION COLORS

2003 WEST DEEP-WATERSTATION COLORS

East Basin ‘86-03 WiDNRJuly and August

East Basin ‘86-03 WiDNRJuly and August

PARAMETERS SAMPLED:PARAMETERS SAMPLED:

WATER CLARITY

TEMPERATURE

DISSOLVED OXYGEN

TOTAL PHOSPHORUS

CHLOROPHYLL

Green Lake’s yearly data from 1980-2003 show:

Green Lake’s yearly data from 1980-2003 show:

valid differences in Secchi data recording droughts and rainy times;

“smoothed” readings reveals cyclic lake responses;

from 1980 - 2003 trend shows some improvement in lake clarity and

lake’s east end is more turbid than west and includes about 68% of the 114 sq mi watershed.

NONPOINT POLLUTION IS OF MAJOR IMPORTANCE

AROUND THIS LAKE

NONPOINT POLLUTION IS OF MAJOR IMPORTANCE

AROUND THIS LAKE

ONLY IN VERY SMALL SITES CAN

SEDIMENT THAT ENTERS THIS LAKE

EVER BE REMOVED. ESTIMATED “FLUSHING TIME” OF

LAKE IS 17 - 21 YEARS ( 2 STUDIES).

SECCHI DATASECCHI DATA

ARE NOT J UST COLLECTED EMOTIONALLY AND THEN THEY BECOME SCIENTIFIC AND

SHOW THE HEALTH OF LAKES WHICH GIVES AN INDICATION OF HOW WE DO ON LAND WITHIN THE WATERSHED.