Post on 25-Jul-2020
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Cazenovia Lake: Monitoring Groundwater PhosphorusDaniel Kopec
SUNY Oneonta Biological Field Station, Cooperstown, NY
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Introduction Cazenovia Lake is a 1,184 acre lake located in
Madison County, NY (20 miles east of Syracuse, NY)
Nutrient enrichment has caused the lake to be
placed on the NYS Priority Waterbodies List as
“threatened” due to excessive aquatic macrophyte
growth and algae. These are symptoms of
eutrophication, suspected to be anthropogenic
The primary goal of this study is to provide the
Town of Cazenovia with an updated comprehensive
lake management plan, with the main focus of
monitoring groundwater nutrient influx and updating
the phosphorus budget for Cazenovia Lake based on
findings. The old 1992 budget is presented in Figure 2Figure 3. Image of an installed
piezometer while another is being
installed adjacent.
Piezometers
What are they?
A metal tube, with a pointed tip at the end
that has holes pre-drilled for entry of
groundwater, and is driven into the sub-surface
What do they do?
They allow the installer to successfully
retrieve groundwater samples from a desired
depth
Why do you need groundwater samples?
To accurately measure nutrient levels going
into a waterbody that may be associated with
residential septic systemsFigure 1. Installation of a piezometer on a
residential property.
Figure 4. Total phosphorus isopleths for the
year of 2014.Figure 6. Dissolved oxygen isopleths for
the year of 2014.
Lake Nutrients
Phosphorus is of greatest concern due to
Cazenovia Lake being phosphorus limited
Water samples were taken at 4 meter
intervals down to 12 meters. 2014 profile
data are plotted in Figure 4
Watershed Nutrients
Main concern with residential septic
systems and obtaining empirical data
Figure 7 displays that the majority of
residential land associated with lake
shoreline
Piezometers were installed at the edges of
5 residential properties with septic systems
to monitor phosphorus concentrations in
groundwater
Calculation of a nutrient budget using the Lake
Loading Response Model (LLRM)
Conducting a spring electrofishing survey to
obtain newer data on the fish community
Rhodamine dye testing to confirm the assumed
relationship between elevated groundwater
phosphorus and septic systems
Continued monitoring of the lake and
piezometers to obtain further data
Nutrient Monitoring
Figure 7.
Land use
attributes of
the
Cazenovia
Lake
watershed.
Figure 8.
Sub-
watershed
boundaries
of the
Cazenovia
Lake
watershed.
Current Work
Figure 5. Preliminary data indicate extreme
variation between sites and dates, with occasional
concentrations in the range of raw wastewater
effluent.
Figure 2.
Phosphorus
budget developed
in 1992 by Coastal
Environmental
Services
8/20/2014 8/30/2014 9/23/2014 10/7/2014 10/18/2014
Pro
pe
rty
1
1920 226 62 113 635
10450 682 39 146 610
4675 410 39 142 143
1160 504 38 467 202
4205 564 42 393 645P
rop
ert
y 2
227 147 20 72 143
171 416 34 49 24
107 17 47 35 32
227 44 89 34 36
4500 812 33 189 700
Pro
pe
rty
3
121 25 26 109 26
91 130 68 25 24
544 488 16 63 37
194 56 47 90 45
126 112 71 80 NA
114 92 161 84 70
3490 102 135 335 80
487 510 86 40 51