OWL WATER SAMPLING DATA ANALYSIS REPORT 2004
INTRODUCTION
During 2004 we again ran two water quality sampling programs simultaneously.
One was the Lake program similar to past years and the second dealt with
Inlet sites all the way to the source near Freeville as had been done in
2003. The Inlet program was again made possible through the assistance of
Jim Hotaling of Cayuga County Soil and Water Conservation District and Anthony
DeCaro of the City of Auburn Water Treatment Plant. They provided Kelly Crossett
who was an Americorp volunteer working with them for the year. Kelly collected
the samples at the various sites on Tuesdays, transported them to the laboratory
at the Auburn Sewage Treatment Plant, and did the actual testing under Andy
Roche's supervision. She collected samples starting on June 15th and ended
on August 31st. All of the data were entered in a computer spreadsheet for
later analysis. Rainfall data was obtained from Cornell University for Ithaca
since it was recognized that the southern tier had distinctly different rainfall
compared to the Auburn area and the majority of the Inlet was closer to Ithaca
than to Auburn. The daily data was converted into weekly totals and entered
into the database this fall.
Lake water quality samples were collected from June 2nd through September 1st. Twenty volunteers collected twenty-five samples weekly for testing at the City of Auburn Waste Treatment Plant for Coliform and turbidity. The volunteers also measured air and water temperatures and noted wind direction and relative strength. They recorded the sky condition and also reported any unusual observations during the week. All of the information was entered in a computer spreadsheet for later analysis. In addition, the City of Auburn provided data on six sites they monitored at the North end of the lake and in the Owasco River to the State Dam near the Lake Avenue Bridge, which was also entered into the database. Rainfall data was provided by Tony DeCaro from the Auburn Weather Monitoring Station at the Water Filter Plant on Swift Street. The daily data was converted into weekly totals and entered into the database this fall.
SUMMARY
The overall conclusion reached from an analysis of the two data sets is that
the water quality in Owasco Lake remains good. The summer of 2004 was extremely
wet with record rainfall recorded in many areas throughout the Finger Lakes.
The high rainfall numbers may have contributed to lower overall fecal Coliform
numbers although some sites such as the Emerson Park Bathing Beach actually
recorded higher numbers resulting in the Beach closure for several weeks.
Turbidity numbers were generally higher this season and water temperature
was depressed. Weed growth in the Lake appeared to be less vigorous than
previous years and milfoil appearance was delayed by several weeks. The Inlet
was very murky throughout the season and most streams feeding the Inlet and
the Lake never dried up this year in contrast to most years.
DETAILED ANALYSIS
To aid in the analysis of data that was collected in 2004, it was again decided
to break the analysis into two portions, the Lake data and the Inlet data.
The Lake data will be addressed first.
PART 1 - Lake Data
As has been done in recent years, selected sites were plotted comparing fecal
Coliform and weekly rainfall over the course of the collection period. The
actual data is attached as Data Sheet 1 and the plots are presented as Charts
1, 2, and 3. The first thing that is revealed is that this past summer had
a lot of rain with most weeks recording an inch or more of rain. Conversely,
the fecal Coliform numbers generally were less than in previous years with
only occasional numbers TNTC signified by a value of 5000 on the graphs.
With exceptions for the Inlet sites, Sucker Brook, and the Bathing Beach
at Emerson Park, the numbers were generally less than 200. One is tempted
to conclude that the rather continuous rainy summer kept the streams washed
out with less accumulation of fecal Coliform. Long Hill Road and Rounds Lane
mimicked each other and closely followed rainfall changes. Sucker Brook and
Dutch Hollow showed a tendency to follow the rainfall data but at a much
more suppressed manner than in previous years. The East Bathing Beach did
not follow the rainfall data very closely. It was sampled both on the East
side and the West side of the Beach area in front of the Pavilion. The data
is shown graphically in Chart 3. It is clear that the East side of the bathing
area has much higher counts than the West side when both are sampled from
the shore. Gary Duckett found that during heavy rain events that the area
behind the Agricultural Museum flooded and large quantities of water were
dumped into the Lake just East of the Bathing area by two large drainage
pipes running under Route 38A. He further learned that the water coming out
of the pipes had TNTC fecal Coliform values. The high readings found in the
Bathing Beach area resulted in the closure of the Bathing Beach for several
weeks in 2004. Effort to isolate the main source of the fecal Coliform entering
the Lake from the drainage pipes has not been successful to date. Additional
work will be needed in 2005 to further address this problem.
The turbidity data for selected Lake sites are presented in Charts 4, 5, and 6. The turbidity seems to follow the rainfall data more closely than the fecal Coliform data did. This is not surprising since higher rainfall amounts would tend to cause more erosion and thus result in higher suspended solids in the run-off. The higher numbers seen for the East side of the Bathing Beach compared to the West side (Chart 6) are another indicator of the strong influence that the pipes under Route 38A are causing on the Bathing area. Overall the turbidity numbers were generally higher in 2004 than in previous years. The water clarity continues to be high probably largely due to the action of the Zebra mussels. Surprisingly, this year the weed growth did not appear to be as prolific as in the past few years. This may be related to the higher cloud cover and lower water temperatures. The emergence of Eurasian milfoil seemed to be several weeks later this year. Again, the variability of the results from observations on the Lake demonstrate how inter-related all of the factors are with climate and weather and what a truly complex entity the Lake is..
The water temperature data are shown in Data Sheet 3 and presented graphically in Charts 7 and 8. The shape of the curves is similar to previous years with the values starting out lower in the beginning and rising to a peak in early August before slowing receding. There is a reverse correlation to rainfall as would be expected. Also, the peak values are lower than in previous years with 25 C. being the top temperature reached. As was noted in previous reports, the Inlet water temperatures measured at Long Hill Road are noticeably lower than the sites in the Lake.
Again this year rainfall data were tabulated both for Auburn and Ithaca and are shown in Data Sheet 4 and plotted in Chart 9. It is apparent that the rainfall data are noticeably different in these two areas with Auburn occasionally receiving more rain than Ithaca. The Lake data were presented with the Auburn data and the Inlet data will be used with the Ithaca data as was done with last year's report. The total rainfall over the period of study was 20.08 inches in Ithaca and 18.99 inches in Auburn.
Part 2 - Inlet Data
The discussion will again follow the format established for the Lake data.
Fecal Coliform results are recorded in Data Sheet 5 and selected sites are
shown graphically in Charts 10, 11, 12, and 13. Several sites gave high fecal
Coliform results on the first sampling date of June 15th. Looking back at
the rain history before the 15th (Chart 9) showed considerable rain at Cornell
the two weeks before the sampling started. This may have contributed to the
high values recorded. The other high values in the main stream on July 13th
and August 31st correlated well with the rain history. The results for Hemlock
Creek and Pine Creek are somewhat different. There is a spike for all the
sites on June 22nd that may be related to a spill or some other contamination
source. It seems that something was introduced above our last sampling point
on Hemlock Creek and Pine Creek which caused high readings all the way down
to the main Inlet stream. The magnitude of the numbers is lower in the Hemlock
Creek and Pine Creek area so that their overall contribution to the fecal
Coliform in the main stream is minimal but the data does show that events
can be isolated by a careful review of good data.
The turbidity data for the Inlet is recorded in data Sheet 6 and presented graphically for selected sites in Charts 14, 15, and 16. As was noted with the Lake data above, the Inlet data does seem to mimic the rainfall trend lines with a couple of unexplained spikes on August 24th at Rt. 38 behind Mineral Springs Rest. And Rt. 38 S. Stevens Rd. near Peru and also on August 17th at Creek Rd. in Hemlock Creek. The turbidities between Locke and Moravia are a bit higher than the points further South toward Freeville and the Pine Creek and Hemlock Creek samples are also lower.
Comparing the overall results for the Inlet in 2004 to 2003, it is clear that the fecal Coliform numbers are lower in 2004 throughout the Inlet section of the watershed. It is certainly possible that the higher amounts of rain in 2004 kept the sources of fecal Coliform washed out and as a result the weekly numbers were lower. As far as I know, no other changes have been made in the watershed such as curtailed manure spreading or reduced fecal coliform discharges from the Sewage Treatment Plants that might help to explain the above observation. Continuing to monitor the Inlet over different weather pattern years will eventually help to explain the overall interactions and variations which are emerging from yearly studies.
ACKNOWLEDGEMENTS AND RECOGNITION
Each year OWL hopes that it can learn a little more about the complex factors
that are impacting Owasco Lake while at the same time realizing that there
are inherent year-to-year variations superimposed on these study parameters.
The invaluable assistance of the OWL Water Quality Monitors allows OWL to
produce a vast amount of data to be studied and evaluated in an attempt to
better understand our watershed. Only with the continued dedicated efforts
of this special class of volunteers can OWL hope to achieve the level of
knowledge and understanding that is sought. The additional assistance from
Cayuga County Soil and Water and the Auburn Water Filtration Plant with the
Americorp volunteer to do the Inlet sampling and testing greatly increased
the data and information that has been generated about the overall watershed.
Andy Roche's invaluable assistance with the testing at the Sewage Treatment
Plant in Auburn is also gratefully acknowledged. On behalf of the OWL Board,
I want to personally thank both the OWL and the Americorp volunteers for
all of their fine efforts and to assure them that their contributions are
deeply appreciated.
Submitted by:
Dick Coalson
Water Quality Coordinator
OWL Executive Board
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