Report: Mild Winter No Help to Lake Hopatcong

While last year’s mild winter may have made residents of the Lake Hopatcong area happy, it may not have been the best thing for the lake itself, as clarity has suffered, according to Princeton Hydro, LLC’s mid-year water quality report. Fred Lubnow, Ph.D. presented the findings to the Lake Hopatcong Commission at its meeting earlier this week.

“Water clarity in the lake was slightly lower in July,” Lubnow said. “The mild winter and somewhat dry spring really didn’t help the lake.”

Lubnow explained that cold winters are important to kill organisms in the lake.

“Snow is important too, because snow pack kills off vegetation,” he added.

The mild winter and warm spring and summer further led to the development of free-floating algae.

Lubnow noted that the algae concentration was slightly increased at the northern end of the lake.
“This is due not only to the weather, but to run-off into the lake,” he said. “The chemicals people use in their homes runs off into the water.”

Water clarity was measured with a Secchi disk in May, June and July. According to the report, “a lake is perceived by a layperson as being ‘dirty’ or ‘scummy’ when the Secchi depth is less than 1.0 meter (3.3 feet).” All stations measured for all three months were at or above the 1.0-meter threshold.

Measurements are taken at 11 stations around the lake. The full report is available here.