HomeMy Public PortalAboutFox Point Lake Water Quality Monitoring Report 2020
Fox Point Lake
2020 Water Quality Monitoring Report
Prepared for
Municipality of Chester
Fox Point Lake Water Quality Monitoring Committee
By
Coastal Action
45 School Street, Suite 403, PO Box 489
Mahone Bay, N.S.
B0J 2E0
February 2021
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Contents
List of Figures .................................................................................................................................. 3
List of Tables ................................................................................................................................... 5
1. Introduction ............................................................................................................................. 6
1.1. Fox Point Lake Background .............................................................................................. 6
1.2. Program Background ........................................................................................................ 7
1.3. Objectives and Scope of Work ......................................................................................... 7
1.4. Review of the 2019 Fox Point Lake Water Quality Monitoring Report ........................... 8
1.5. Changes to the 2020 Fox Point Lake Water Quality Monitoring Program ...................... 8
2. Water Quality Monitoring Results ........................................................................................... 9
2.1. Water Sampling ................................................................................................................ 9
2.1.1. Physical Water Quality Parameters .......................................................................... 9
2.1.2. Chemical Water Quality Parameters ...................................................................... 17
2.1.3. Biological Water Quality Parameters ...................................................................... 21
2.2. Sediment Sampling ......................................................................................................... 22
2.2.1. Metals ..................................................................................................................... 23
2.2.2. Phosphorus ............................................................................................................. 25
3. Discussion .............................................................................................................................. 26
3.1. Algae Blooms in Fox Point Lake ...................................................................................... 26
3.2. Trophic State of Fox Point Lake ...................................................................................... 26
3.3. Potential for Nutrient Enrichment of Fox Point Lake ..................................................... 28
4. Recommendations ................................................................................................................. 30
5. References ............................................................................................................................. 31
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List of Figures
Figure 1: Drainage basin and sampling sites of Fox Point Lake. ..................................................... 6
Figure 2: Single point monthly water discharge from the three streams and the South Culvert
monitored at FPL from June-October 2020 along with Environment Canada rainfall data for the
same period. ................................................................................................................................. 10
Figure 3: Mean (blue line) stream discharge rates from June to October 2016 to 2020 for
comparison. The maximum and minimum ranges of stream discharge are designated by the
grey area. ...................................................................................................................................... 10
Figure 4: Monthly water temperature from the lake and three stream sites at FPL from June-
October 2020. Red line indicates the 20oC water temperature threshold for cold-water fish
species. .......................................................................................................................................... 11
Figure 5: Monthly water temperature depth-profiles from the lake site at FPL from June-
October 2020. Note that 20oC is the water temperature threshold for cold-water fish species. 12
Figure 6: Monthly DO from the lake and three stream sites at FPL from June -October 2020. Red
line indicates the 6.5 mg/L DO minimum for aquatic organisms as set by the CCME. ................ 13
Figure 7: Mean and minimum summer DO concentrations from July-September from 2016 to
2020 for comparison. The red line signifies the 6.5 mg/L threshold for DO minimum for aquatic
organisms as set by the CCME. ..................................................................................................... 14
Figure 8: Monthly dissolved oxygen depth-profiles from the lake site at FPL from June-October
2020. Red line indicates the 6.5 mg/L DO minimum for aquatic organisms, as set by the CCME.
....................................................................................................................................................... 15
Figure 11: Monthly total dissolved solids from the lake and three stream sites at FPL from Jun e-
October 2020. ............................................................................................................................... 17
Figure 12: Monthly total suspended solids from the lake and three stream sites at FPL from
June-October 2020........................................................................................................................ 18
Figure 13: Monthly total phosphorus concentrations from the lake, three stream sites and south
culvert site at FPL from June-October 2020. Red solid line indicates the 0.03 mg/L MOECC
guideline for streams and rivers, while the red dotted line indicates the 0.02 mg/L MOECC
guideline for lakes. ........................................................................................................................ 19
Figure 14: Mean and maximum phosphorus concentrations from June-October from 2016 to
2020 for comparison. Note that the scales of the y axis are different on each of the graphs. ... 20
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Figure 15: Monthly total nitrogen concentrations from the lake and three stream sites at FPL
from June-October 2019. Red line indicates the 0.9 mg/L guideline for freshwater
environments, as set by Dodds and Welch (2000). ...................................................................... 20
Figure 16: Mean and maximum nitrogen concentrations from June-October 2016 to 2020 for
comparison. .................................................................................................................................. 21
Figure 17: Monthly fecal bacteria concentrations from the lake and the three stream sites at FPL
from June-October 2020. Red solid line indicates the Health Canada 400 CFU/100 ml limit for
primary recreation in freshwater. ................................................................................................ 22
Figure 18: Phosphorus concentrations in sediment samples from lake and stream sites sampled
on September 28th, 2020. ............................................................................................................. 25
Figure 19: Carlson TSI for FPL using the mean Secchi disk depth (transparency), mean
chlorophyll α concentration and mean total phosphorus concentration within FPL in 2020. From
Carlson, 1977. ............................................................................................................................... 27
Figure 20: Comparison of FPL TSI scores from 2015 to 2020 and trophic states, using the Carlson
(1977) trophic equations for total phosphorus, chlorophyll α, and Secchi disk. ......................... 28
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List of Tables
Table 1: Concentration of metals within site sediment samples sampled on September 28 th,
2020. Interim sediment quality guideline (ISQG) is the recommendation by CCME of total
concentrations of chemicals in surficial sediment, while the probable effect level (PEL) is the
CCME upper value in which adverse effects are expected (CCME, 2001). Nova Sco tia
environmental quality standards (NSEQS) are sediment guidelines specifically for contaminated
sites set by Nova Scotia Environment (NSE, 2014). Light yellow indicates parameters
approaching one of the guidelines, while red indicates an exceedance of on e of the guidelines.
....................................................................................................................................................... 23
Table 2: Summary of three years of guideline exceedances of metals in sediment samples from
SW Cove and South Inlet sampling locations. .............................................................................. 24
Table 3: The results of the 2020 TSI calculations for the 3 associated water quality parameters.
....................................................................................................................................................... 27
Table 4: Nutrient concentrations from surface and depth waters (below the thermocline) within
FPL, obtained on September 28th, 2019. ...................................................................................... 29
Table 5: Nutrient concentrations from the two South Inlet sites following rainfall events in 2019
and 2020. ...................................................................................................................................... 30
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1. Introduction
1.1. Fox Point Lake Background
Fox Point Lake (FPL) is a 1.4 km2 lake located on the Aspotogan Peninsula, within the Municipality
of Chester, Nova Scotia (Figure 1). FPL contains 11 small islands and has an average depth of 4.9
m (Beanlands, 1980). The lake drains an area of 8 km2, with two inlet streams – the north and
south - and one outlet draining into St. Margaret’s Bay. The northern inlet drains a forested
region, crossing a wetland before reaching the lake, while the southern inlet runs through the
Aspotogan Golf Course. Residential properties, both year-round and seasonal, line the lake
perimeter.
Figure 1: Drainage basin and sampling sites of Fox Point Lake.
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1.2. Program Background
In 2014, due to concerns from residents about the water quality of FPL, the Municipality of
Chester created the Fox Point Lake Water Quality Monitoring Committee (WQMC). In relation
to development around the lake by Aspotogan Ridge, a 550-acre community with original
development plans for 344 residential units and an 18-hole golf course, the rate of rainfall-
induced sedimentation plumes in FPL spiked. The sedimentation events, occurring near the
southern inlet which drains from the golf course, raised the concerns of citizens for the health of
FPL.
To monitor the water quality conditions and track changes within the lake, Coastal Action was
contracted in 2015 by the Municipality of Chester to join the WQMC and develop and implement
a water quality program. The program focuses on four site locations (Figure 1) chosen to monitor
water quality incoming, within, and exiting the lake. Monitoring activities within the program are
conducted by a small group of trained volunteers, with the support of Coastal Action staff.
Further details on the program can be found in the Fox Point Lake Water Quality Monitoring
Program (2015), and program results are found in the Fox Point Lake Water Quality Monitoring
Reports from 2015-2019; all are available on request from the Municipality of Chester.
1.3. Objectives and Scope of Work
The objective of this program is to provide a multi-year water quality baseline of Fox Point Lake
and monitor changes to the lake’s trophic state to help inform decisions made regarding
development in the region and its effects on water quality. Within the WQMC, Coastal Action’s
scope of work includes:
• Ordering and ensuring correct bottles from Bureau Veritas Laboratories (BV Labs)
(formerly Maxxam Analytics)
• Creating and printing waterproof field sheets for each sampling month
• Calibrating and caring for the MODL-MOC YSI monthly
• Coordinating with volunteers for sampling days
• Coordinating the volunteer-collected water level and rainfall measurements
• Conducting one-time rainfall-dependent sampling with volunteers
• Conducting one-time field sediment sampling with volunteers
• Conducting field water sampling monthly with volunteers
• Conducting algal bloom sampling with volunteers, as needed
• Dropping off water samples at BV Labs in Bedford, NS
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• Transferring data from field sheets, lab reports, and volunteers into a database and
analyzing data
• Attending WQMC meetings and presenting water quality results
• Preparing the Fox Point Lake 2020 Water Quality Monitoring Program Report to
summarize results and recommendations for water quality related to Fox Point Lake .
1.4. Review of the 2019 Fox Point Lake Water Quality
Monitoring Report
The trophic state of FPL was determined to be oligotrophic and approaching mesotrophic during
each sampling year from 2015 through 2019 indicating that there have not been any major
changes in the biological productivity of the lake during this period.
Thermal and oxygen profiles were conducted at one lake site in 2019 at the deepest point.
Thermal stratification of the lake was observed during the temperature profile, while dissolved
oxygen indicated a depletion of oxygen at depth, with concentrations below 3 mg/L recorded in
the bottom waters of the lake.
There was one reported algal bloom in 2019 in late July. However, the sample was lost by UPS
in transit to an out-of-province lab and therefore was not sampled for toxicity. The last confirmed
cyanobacteria bloom on the lake occurred in 2017.
Three of the four FPL sites did not exceed phosphorus guidelines in 2019. The South Inlet site
exceeded the 0.03 mg/L MOECC stream guideline as it has done from 2015-2018. Despite lower
phosphorus concentrations at the South Inlet in 2018, the maximum recorded phosphorus
concentration in 2019 was 0.2 mg/L, double the maximum recorded concentration in 2018. The
possible recovery from excessive phosphorous loading reported last year seems to be short lived.
Sediment was sampled at the Southwest Cove and South Inlet sites to test for metal
concentrations. At the Southwest Cove site, arsenic, cadmium, lead, mercury, and selenium were
all elevated; arsenic, cadmium and lead exceeded ISQG guidelines, and selenium exceeded NSE
guidelines. For the South Inlet, increases in arsenic and mercury were detected with arsenic
exceeding NSE guideline and mercury exceeding ISQG guidelines. This suggests elevated
concentrations due to erosion and disturbance in the catchment near these sites.
1.5. Changes to the 2020 Fox Point Lake Water Quality
Monitoring Program
To address the recommendations after the 2019 sampling season, a weather station has been
installed at a residential home on the lake to reduce volunteer time and to ensure continued
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monitoring of rainfall in the region. The second sample site that was added in 2019 in the South
Inlet stream was sampled again during the 2020 season following a heavy rainfall event. This
new site is located downstream of the original South Inlet site and immediately downstream of
a new residential property which has livestock and manure within the drainage area of the
stream, thus posing a risk of nutrient and bacteria contamination from overland runoff.
In addition, Maxxam has changed ownership in 2019 and is now run under the name Bureau
Veritas Laboratories (BV Labs). They use the same infrastructure and protocols as Maxxam;
therefore results are comparable.
2. Water Quality Monitoring Results
2.1. Water Sampling
2.1.1. Physical Water Quality Parameters
2.1.1.1. Stream Discharge
Stream discharge rates were monitored at the two inlet sites – North and South – and the Outlet
site monthly from June to October 2020 (Figure 2). The discharge of a secondary South Inlet
(South Culvert) site was also measured once, during the rainfall-dependent sampling event in
September 2020. As stream depth and width can affect stream discharge, each stream’s depth,
width, velocity, and discharge are measured and calculated on an individual basis. Due to the
inability to connect to the rain gauge over the summer, rainfall data was taken from the
Environment Canada historical database for the months of June through October 2020 from the
weather station in Halifax (Figure 2).
The South Inlet had the lowest and most consistent flow throughout the sampling period , while
the North Inlet had a slightly greater discharge with a noticeable increase in flow in August which
corresponds to consecutive rain events (Figure 2). The discharge from the Outlet was variable
throughout the sampling period. There is a lagged response between the rainfall event and an
increase in flow at the outlet which can be observed for the September sample and rainfall event
which were sampled three days apart.
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Overall, there is a trend of increasing variability in the rate of discharge at both the South and
North Inlet sites beginning in 2018 while the outlet has remained relatively stable.
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Figure 2: Single point monthly water discharge from the three streams and the South Culvert monitored at FPL from June -
October 2020 along with Environment Canada rainfall data for the same period.
Figure 3: Mean (blue line) stream discharge rates from June to October 2016 to 2020 for comparison. The maximum and
minimum ranges of stream discharge are designated by the grey area.
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2.1.1.2. Water Temperature and Stratification of Fox Point Lake
Water temperatures from the four FPL sites were recorded monthly during the 2020 program;
temperatures ranged from 11.9°C to 24.1°C (Figure 4) which is an increase from the 2019 range
of 8.9 °C to 22.7 °C. The South Inlet was the only site to consistently be cooler than the other
sites through the sampling period. The highest temperature recorded was at the Outlet site in
July.
Three sites exceeded the 20oC temperature threshold for cold-water fish species (Nova Scotia
Salmon Association [NSSA], 2014) in July and August. The sites with exceedances were the
Outlet, Lake and for the first time since 2016, the North Inlet site (Figure 4). Although the three
sites exceeded the threshold, the deeper waters within the lake, the deep cold-water pools
within the Outlet, and the one colder inlet stream can provide thermal refuge for fish during the
hotter months. However, in previous years the North Inlet was also a source of cooler water
refuge which might not continue to be the case during the summer months.
A monthly water profile was also constructed from within the lake during the 2020 sampling
period (Figure 5). Between July to September, the profile shows the development and
establishment of a stratified water column, with warmer waters remaining at the surface
(epilimnion) and the cooler, more-dense waters settling to the lake bottom (hypolimnion). The
thermocline, the depth at which the water temperature rapidly changes, is located at 2-m water
depth in July and 10-m depth in August. The August data was taken under windy conditions and
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1-Jun-20 1-Jul-20 1-Aug-20 31-Aug-20 1-Oct-20 31-Oct-20Water Temperature (°C)North Inlet South Inlet Lake Outlet South Culvert
Figure 4: Monthly water temperature from the lake and three stream sites at FPL from June-October 2020. Red line indicates the
20oC water temperature threshold for cold-water fish species.
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thus the depth of the thermocline is an estimate, however it was around 10 m lake-depth in 2019
so the results are consistent with previous years. Although the surface waters of the lake
exceeded the 20oC threshold for cold-water fish in July and August, temperatures were below
the threshold at depths greater than this.
Due to the density differences between the epilimnion and hypolimnion, little mixing occurs
within the thermally stratified parts of the lake. By the end of September (during the rainfall
event), readings determined that stratification had begun to deteriorate (Figure 5). October
displayed a minimal thermocline, with temperatures remaining consistent down to a depth of 15
m. Fall turnover of the lake is expected to occur in October when the lack of stratification
encourages mixing of the waters at all depths.
2.1.1.3. Dissolved Oxygen and Stratification of Fox Point Lake
Dissolved oxygen (DO) within the water was recorded monthly at all four sites, from June to
October 2020 (Figure 6). DO ranged from 2.99 mg/L to 11.08 mg/L. The North Inlet consistently
had the lowest DO concentrations, while the highest concentrations were recorded within the
lake. The low velocity and minimal incline of the North Inlet stream may be factors in the low DO
measurements, as these factors limit the water’s ability to engulf oxygen from the air due to lack
of turbulence of the water.
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Figure 5: Monthly water temperature depth-profiles from the lake site at FPL from June-October 2020. Note that 20oC is the
water temperature threshold for cold-water fish species.
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The low DO in the North Inlet may negatively affect aquatic organisms. DO is a requirement for
the survival of aquatic organisms, with a minimal threshold of 6.5 mg/L (red line, Figure 6) set by
the Canadian Council of Ministers of the Environment (CCME) for cold-water species (CCME,
1999). Each site had at least one instance of levels below the threshold during the sampling
season. The Lake site recorded 6.35 mg/L in July, but otherwise remained above the threshold.
The North Inlet was consistently below the threshold except for after the rainfall event in
September and quickly fell below three days later. The Outlet and South Inlet each had values
lower than 6.5 mg/L in September (5.83 mg/L and 4.10 mg/L, respectively). Although fish can
survive in low-DO environments for short periods of time, the low-DO environment in the North
Inlet may be causing physiological stress to fish in that stream.
Although the low-DO concentrations in the North Inlet are concerning, they are consistent with
previous years (Figure 7). The reduction in DO during the summer is a consistent annual trend
due to the decreased ability for warmer waters to dissolve oxygen and the higher DO demand
during the growing season, leaving the Lake the only refuge during August.
Overall, the 2020 data compared to the previous years of monitoring demonstrates that the
North Inlet and South Inlet sites have consistently low average DO concentrations and a ll but the
Lake site have had minimum recorded DO concentrations that fall below the CCME guidelines for
each of the reporting years (Figure 7).
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Figure 6: Monthly DO from the lake and three stream sites at FPL from June-October 2020. Red line indicates the 6.5
mg/L DO minimum for aquatic organisms as set by the CCME.
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DO was also measured within the lake during the monthly water depth profiles (Figure 8). The
concentration of DO was uniform throughout the water column in June. By July, a reduction in
DO was observed in surface waters from 11.08 mg/L in July to 9.04 mg/L in August, coinciding
with the beginning of lake thermal stratification. There is also a secondary decrease in DO
concentration in July occurring between four and seven metres lake-depth where DO
concentrations range from 6.01 to 6.43 mg/L and then return to 8.0 mg/L at 9-m lake-depth. By
August, there appears to be an established stratified DO column in the lake, which remains at 10-
m water-depth for August and September (Figure 8). The reduction of DO concentrations within
the hypolimnion is associated with minimal mixing of the water column due to the presence of a
thermocline in the lake. The lack of mixing and minimal DO inputs from the epilimnion, along
with the continued oxygen demand from organisms, result s in the decline in DO concentrations
in the hypolimnion until the water column mixes again during fall turnover (Smith and Bella,
1973). By October, fall cooling and mixing has begun bringing DO deeper into the water column
with the stratification extending to 15-m water-depth.
The DO depth-profile within the lake appears to be a clinograde curve, with a negative
heterograde curve occurring in July. A clinograde curve occurs when DO decreases in the
hypolimnion layer due to high rates of respiration and an increase in decomposition as lake
productivity increases predominantly during the summer months. This type of curve was
observed from August to October of this sampling year. A negative heterograde curve can occur
when a pocket of low DO occurs mid-profile due to the accumulation and high oxygen demand
of decomposing organic matter being caught in the density boundary of the water column
(Mackie, 2004) which was observed in July (Figure 8). A negative heterograde curve has also
been confirmed in previous years in FPL.
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Figure 7: Mean and minimum summer DO concentrations from July-September from 2016 to 2020 for comparison. The red line signifies the
6.5 mg/L threshold for DO minimum for aquatic organisms as set by the CCME.
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Figure 8: Monthly dissolved oxygen depth-profiles from the lake site at FPL from June-October 2020. Red line indicates the 6.5
mg/L DO minimum for aquatic organisms, as set by the CCME.
The summer stratification of the lake may cause stress to organisms within the lake. During the
August to October monthly profiles, the hypolimnion’s DO concentrations fell below 6.5 mg/L.
August results are uncertain due to the windy day they were taken , which caused the probe not
to descend straight into the water column (Figure 8). It does however provide values that were
present in the lake. The decline in DO concentrations below the CCME threshold occurs at 11 m
for September and does not become hypoxic (<2 mg/L) until below 21 m. October DO
concentrations did not fall below the CCME guideline until after 15-m water-depth; however, did
reach hypoxic conditions at 16 m and anoxic conditions (<1 mg/L) below 18 m (Figure 8). These
low dissolved oxygen conditions can reduce the ability to support aquatic life (United States
Geological Survey [USGS], 2014; Brylinsky, 2004).
2.1.1.4. pH
pH, a measurement of the acidity of a liquid, was measured monthly at each of the four FPL sites
(Figure 9). Although most pH measurements fell below the 6.5-pH threshold set by the CCME
(CCME, 2002), the acidity of the FPL waters is not a significant concern. As Nova Scotia has
experienced high amounts of acid precipitation in the past, and its geology limits the
replenishment of base cations to soils (NSSA, 2015), surface waters within the province are
generally lower than the 6.5-pH threshold. In addition, though the FPL sites’ pH values are lower
than 6.5 pH, many fish species can survive in waters >5.0-pH (NSSA, 2014) and therefore it
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appears that most of the time (save for the low sub-5.0 pH measurements in the Lake in August,
and North Inlet in September and October, Figure 9) the acidity of the waters at FPL pose minimal
threat to organisms.
Generally, the year-to-year pH trends demonstrate that they are rising at all the stream sites;
however, there is a slightly decreasing trend in the pH of the lake (Figure 10).
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Figure 9: Monthly pH from the lake and three stream sites at FPL from June-October 2020. Red line indicates the 6.5-pH
minimum for aquatic organisms, as set by the CCME.
Figure 10: Mean and minimum pH values from June-October 2020 at the four sites, with 2016 to 2019 results for comparison.
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2.1.1.5. Total Dissolved Solids
Total dissolved solids (TDS) from the four FPL sites sampled monthly from June-October 2020
ranged from 23 mg/L to 44 mg/L (Figure 11). The highest TDS concentrations were consistently
measured within the North Inlet, while the remaining three sites never exceeded 30 mg/L.
Although TDS concentrations within FPL are higher than other locations and previous years, TDS
does not appear to be a problem for aquatic organisms. There is no guideline for TDS set by the
CCME for the protection of aquatic health; however, Hinch and Underwood (1985) found that
pristine Nova Scotian lakes had an average of 20 mg/L. The lake site within the FPL program had
an average of 29 mg/L in 2020, suggesting that the lake is not pristine and to some extent affected
by sedimentation. However, the average is less than the 33.3 mg/L recorded in 2019. The
presence of high TDS is not necessarily harmful as dissolved materials can be from both
anthropogenic and natural sources. As TDS does not have a guideline for the protection of
aquatic organisms, TDS concentrations do not appear to be detrimental to FPL.
Figure 9: Monthly total dissolved solids from the lake and three stream sites at FPL from June-October 2020.
2.1.2. Chemical Water Quality Parameters
2.1.2.1. Total Suspended Solids
Total suspended solids (TSS) were measured as the value of solids suspended in a water column
which do not pass through a 45 µm glass fiber filter. For FPL, TSS ranged from <1 mg/L to 14
mg/L (Figure 12). The average monthly TSS concentration was 7.58 mg/L for 2020, up from 4.25
mg/L recorded in 2019 and 2.09 mg/L in 2018. The South Inlet had consistently higher recorded
levels of TSS compared to the other sites than in previous years which may be associated with
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overland flow influences adding sediment to both the stream and the lake. The TSS at the Lake
site has remained low for 2020 with a mean concentration of 1.32 mg/L, well below the average
3.0 mg/L background concentration of Nova Scotia lakes repo rted by Hinch and Underwood
(1985). TSS concentrations are not a concern and are consistent with Nova Scotian lakes and
previous FPL sampling years. As the CCME has a guideline of a 10 mg/L allowable increase from
baseline in waterbodies with TSS ≤ 100 mg/L (CCME, 2002), the increases observed in FPL do not
appear to be a threat to aquatic organisms.
Figure 10: Monthly total suspended solids from the lake and three stream sites at FPL from June-October 2020.
2.1.2.2. Total Phosphorus
Total phosphorus within FPL, monitored and analyzed at BV Labs monthly from June to October
2019, ranged from <0.005 mg/L to 0.09 mg/L (Figure 13). The highest phosphorus concentrations
were consistently measured at the South Inlet, and were significantly different from the North
Inlet, Outlet, and Lake sites. The phosphorus concentration obtained at-depth, below the
thermocline in the lake, was 0.012 mg/L.
Ontario’s Ministry of Environment and Climate Change (MOECC) has established two guideli nes
for phosphorus in waterbodies: ≤ 0.02 mg/L for lakes, and ≤ 0.03 mg/L for rivers and streams
(Ontario’s Ministry of Environment [MOE], 1979). The South Inlet was the only site to exceed the
phosphorus guidelines for streams in 2020 as well as the South Culvert site. The phosphorus
concentrations of the lake never exceeded 0.01 mg/L. There was one sample from the North
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16
1-Jun-20 1-Jul-20 1-Aug-20 31-Aug-20 1-Oct-20 31-Oct-20Total Suspended Solids (mg/L)North Inlet South Inlet Lake Outlet South Culvert
Fox Point Lake 2020 Report | Municipality of Chester | Coastal Action | 2020
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Inlet on September 25th after the rainfall which approached the 0.03 mg/L threshold with a
concentration of 0.028 mg/L.
As mentioned above, the South Inlet site exceeded the 0.03 mg/L MOECC stream guideline for
phosphorus during the entire 2020 sampling season. This sample site has exceeded the MOECC
stream guideline for phosphorus for each sample obtained during the 2015, 2016, 2017, and 2018
field seasons. As there are few natural phosphorus inputs into the environment, elevated
concentrations indicate an anthropogenic source.
Although the South Inlet exceeded MOECC stream phosphorus guidelines, phosphorus
concentrations within the stream appear to be relatively steady and decreasing slightly over the
past three years (Figure 14). Although phosphorus concentrations in the South Inlet are the
highest of the four FPL sampling sites, the reduction in phosphorus concentrations suggests that
the stream may be slowly recovering from nutrient enrichment and that the control measures
placed along any developments feeding the South Inlet are helping.
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.10
1-Jun-20 1-Jul-20 1-Aug-20 31-Aug-20 1-Oct-20 31-Oct-20Total Phosphorous (mg/L)North Inlet South Inlet Lake Outlet South Culvert
Figure 11: Monthly total phosphorus concentrations from the lake, three stream sites and south culvert site at FPL from June-
October 2020. Red solid line indicates the 0.03 mg/L MOECC guideline for streams and rivers, while the red dotted line indicates
the 0.02 mg/L MOECC guideline for lakes.
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2.1.2.3. Total Nitrogen
Total nitrogen analysis was performed by BV Labs monthly from June to October 2020 for all four
FPL sites along with the one South Culvert sample (Figure 15). Total nitrogen ranged from 0.020
mg/L to 0.771 mg/L; the highest nitrogen concentration was recorded at the North Inlet, while
the highest mean nitrogen concentration was recorded at the South Inlet (Figure 15). The
nitrogen concentration obtained at-depth, below the thermocline in the lake, was 0.288 mg/L.
0.000
0.020
0.040
0.060
0.080
0.100
0.120
0.140
0.160
2016 2017 2018 2019 2020Dissolved Oxygen (mg/L)Mean P
North Inlet South Inlet Outlet Lake
0.000
0.050
0.100
0.150
0.200
0.250
0.300
0.350
2016 2017 2018 2019 2020Dissolved Oxygen (mg/L)Maximum P
North Inlet South Inlet Outlet Lake
Figure 12: Mean and maximum phosphorus concentrations from June-October from 2016 to 2020 for comparison. Note that the scales
of the y axis are different on each of the graphs.
Figure 13: Monthly total nitrogen concentrations from the lake and three stream sites at FPL from June-October 2019. Red line
indicates the 0.9 mg/L guideline for freshwater environments, as set by Dodds and Welch (2000).
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1-Jun-20 1-Jul-20 1-Aug-20 31-Aug-20 1-Oct-20 31-Oct-20Total Nitrogen (mg/L)North Inlet South Inlet Lake Outlet South Culvert Lake Depth
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Overall, the nitrogen levels in the lake have remained consistent since 2016 (Figure 16), while
there is a slight decrease at the South Inlet and a slight increase at the North Inlet site. The Outlet
showed a spike in 2019 and returned to similar concentrations that were present in the previous
sampling years.
2.1.3. Biological Water Quality Parameters
2.1.3.1. Fecal Bacteria
In 2019, the FPL Monitoring Program switched from monitoring fecal coliforms to monitoring
Escherichia coli (E. coli) to align with Health Canada’s recommended use of E. coli as the primary
indicator of fecal contamination in freshwaters. Health Canada has set primary and secondary
recreational contact guidelines for E. coli in freshwaters, ≤400 CFU/100 ml and ≤1000 CFU/100
ml, respectively (Health Canada, 2012).
Fecal bacteria samples were collected from each FPL site monthly during the 2020 field season
(Figure 17). Samples ranged from <10 CFU/100 ml to 200 CFU/100 ml. The South Inlet had the
highest E. coli concentration for each of the sampling dates including October (Figure 17) where
it had the same value as the Outlet site (20 cfu/100 ml). The Lake site had a mean of 10 cfu/100
ml throughout the sampling period.
During the rainfall-dependent sampling event, bacteria concentrations spiked in the South Inlet,
however values were higher at the same site three days later which might suggest a lag in the
response between the rain event and the resulting run off into the stream. There was no increase
in bacteria at each of the other sites after the rain event.
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
2016 2017 2018 2019 2020Dissolved Oxygen (mg/L)Mean Recorded N
North Inlet South Inlet Outlet Lake
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
2016 2017 2018 2019 2020Dissolved Oxygen (mg/L)Maximum Recorded N
North Inlet South Inlet Outlet Lake
Figure 14: Mean and maximum nitrogen concentrations from June-October 2016 to 2020 for comparison.
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During the 2018 field season, construction of a house and barn occurred just below the South
Inlet sampling site. Livestock and manure on this property increase the risk of fecal bacteria
contamination of the South Inlet due to the increased presence and potentia l leaching of animal
feces into the water from overland flow. This site continued to be monitored in 2020 during the
rain event and the 2020 results did not have appreciable levels of E. coli in the sample from that
location.
2.1.3.2. Microcystins and Algal Blooms
There was one report of a possible algal bloom at Fox Point Lake in 2020 on July 27th. A sample
was collected and sent for analysis however, it was lost in transit by UPS. The potential
cyanobacteria bloom remains unconfirmed.
2.2. Sediment Sampling
Sediment sampling from the Southwest side of the lake (known as ‘SW Cove’) and from the South
Inlet occurred on September 28th, 2020. The substrate from both sites was analyzed for metals,
phosphorus, and orthophosphate, to assess the risk of internal nutrient loading within the lake
and potential risk from accumulation of metals within the sediments (Tables 1 & 2).
0
50
100
150
200
250
300
350
400
450
500
1-Jun-20 1-Jul-20 1-Aug-20 31-Aug-20 1-Oct-20 31-Oct-20E. coli (cfu/100ml)North Inlet South Inlet Lake Outlet South Culvert
Figure 15: Monthly fecal bacteria concentrations from the lake and the three stream sites at FPL from June-October 2020. Red
solid line indicates the Health Canada 400 CFU/100 ml limit for primary recreation in freshwater.
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2.2.1. Metals
Table 1: Concentration of metals within site sediment samples sampled on September 28th, 2020. Interim sediment quality
guideline (ISQG) is the recommendation by CCME of total concentrations of chemicals in surficial sediment, while the probable
effect level (PEL) is the CCME upper value in which adverse effects are expected (CCME, 2001). Nova Scotia environmental quality
standards (NSEQS) are sediment guidelines specifically for contaminated sites set by Nova Scotia Environment (NSE, 2014). Light
yellow indicates parameters approaching one of the guidelines, while red indicates an exceedance of one of the guidelines.
Sediment Sample
Concentrations
Sediment Concentration
Guidelines
Metals UNITS SW Cove
2020
South Inlet
2020 ISQG PEL NSEQS RDL 2020
Acid Extractable Aluminum (Al) mg/kg 14000 6600 10
Acid Extractable Antimony (Sb) mg/kg ND ND 25 2
Acid Extractable Arsenic (As) mg/kg 9.1 9.8 5.9 17 17 2
Acid Extractable Barium (Ba) mg/kg 69 46 5
Acid Extractable Beryllium (Be) mg/kg 2.2 ND 2
Acid Extractable Bismuth (Bi) mg/kg ND ND 2
Acid Extractable Boron (B) mg/kg ND ND 50
Acid Extractable Cadmium (Cd) mg/kg 0.48 ND 0.6 3.5 3.5 0.3
Acid Extractable Chromium (Cr) mg/kg 12 5.4 37.3 90 90 2
Acid Extractable Cobalt (Co) mg/kg 3.3 2.9 1
Acid Extractable Copper (Cu) mg/kg 18 7.3 35.7 197 197 2
Acid Extractable Iron (Fe) mg/kg 11000 11000 47,766 50
Acid Extractable Lead (Pb) mg/kg 61 21 35 91.3 91.3 0.5
Acid Extractable Lithium (Li) mg/kg 20 13 2
Acid Extractable Manganese (Mn) mg/kg 420 420 1,100 2
Acid Extractable Mercury (Hg) mg/kg 0.23 0.17 0.17 0.486 0.486 0.1
Acid Extractable Molybdenum (Mo) mg/kg ND ND 2
Acid Extractable Nickel (Ni) mg/kg 8.1 4.2 75 2
Acid Extractable Phosphorus (P) mg/kg 1200 660 100
Acid Extractable Rubidium (Rb) mg/kg 16 13 2
Acid Extractable Selenium (Se) mg/kg 2.1 0.71 2 1
Acid Extractable Silver (Ag) mg/kg ND ND 1 0.5
Acid Extractable Strontium (Sr) mg/kg 16 17 5
Acid Extractable Thallium (Tl) mg/kg 0.18 0.15 0.1
Acid Extractable Tin (Sn) mg/kg 3.7 1.3 1
Acid Extractable Uranium (U) mg/kg 11 7.5 0.1
Acid Extractable Vanadium (V) mg/kg 25 9.4 2
Acid Extractable Zinc (Zn) mg/kg 48 35 123 315 315 5
Orthophosphate (P) mg/kg 0.30 0.33 0.05
*RDL = Reportable Detection Limit; ND = Not Detected
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Three guidelines are used for comparison for the sediment analysis; the CCME’s recommended
interim sediment quality guideline (ISQG), the CCME’s probable effect level (PEL), and the Nova
Scotia Environmental Quality Standards (NSEQS) contamination threshold. The results for 2020
at SW Cove indicate that arsenic and lead exceeded the ISQG guidelines again this year and for
the first time, mercury also exceeded these guidelines, while selenium exceeded the NSEQS
guidelines (CCME, 2001; NSE, 2014) for the second year. Arsenic, lead, and mercury levels were
greater than 2019 concentrations while selenium, which was still high, had lower levels than 2019
(Table 2). Cadmium, which exceeded the ISQG guidelines last year, fell below the threshold in
2020. Due to the increase of metals exceeding these guidelines, the impacts of pollution have
increased in the lake and may begin to pose a risk to aquatic life.
Table 2: Summary of three years of guideline exceedances of metals in sediment samples from SW Cove and South Inlet sampling
locations.
SW Cove South Inlet
UNITS 2018 2019 2020 2018 2019 2020
Acid Extractable Arsenic (As) mg/kg 6 6.1 9.1 10 22 9.8
Acid Extractable Cadmium (Cd) mg/kg ND 0.8 0.48 0.4 0.37 ND
Acid Extractable Lead (Pb) mg/kg 2.6 50 61 33 31 21
Acid Extractable Mercury (Hg) mg/kg ND 0.16 0.23 0.21 0.17 0.17
Acid Extractable Selenium (Se) mg/kg ND 2.7 2.1 1.1 1 0.71
Within the South Inlet, arsenic and mercury concentrations continue to pose a risk to aquatic
organisms. Arsenic concentrations did improve however and now only exceed the ISQG
guidelines, while mercury concentrations remained the same as last year, exceeding the ISQG
guidelines. Organisms living within this stream should be considered at-risk for bioaccumulation.
Any fisheries should be limited to the lake, where the inputs from the South Inlet are diluted and
do not appear to affect the overall sediment quality within t he lake.
As discussed in Section 2.1.3.1, development along the South Inlet may be detrimental to water
quality. The development of the residential property near the stream may pose issues with water
quality within the remaining stretch of the South Inlet. As the South Inlet’s sediment has been
contaminated with heavy metals previously, disturbance of the sediment and additions of more
pollutants to the sediment can result in the release and contamination of metals into the water,
thereby affecting water quality and organisms. Overall, the metals are increasing at the SW Cove
location while concentrations seem to be improving at the South Inlet site compared to last year.
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2.2.2. Phosphorus
Concentrations of both acid extractable (total) phosphorus and bioavailable orthophosphate
were analyzed within both sediment sites’ substrates. Within the SW Cove, the concentration of
orthophosphate was 0.3 mg/kg in 2020, 0.025 % of total phosphorus, slightly increasing from
2019 (0.022 %). The increase in the fraction of orthophosphate for 2020 coincides with an
increase in total phosphorus concentrations (Figure 18a). Within the South Inlet,
orthophosphate concentration was 0.33 mg/kg, 0.05% of total phosphorus which is a decrease
from 2019. Total phosphorus in the South Inlet also decreased in 2020 (Figure 18b).
Although there is a decrease in the fraction of orthophosphate in the sediment of the South Inlet
and only a slight increase in SW Cove, the overall continued increase in total phosphorus
concentrations suggests that there is more bioavailable phosphorus within the lake, which can
result in nutrient enrichment during fall turnover if the available orthophosphate stores increase
and are not assimilated.
The total phosphorus concentrations within the sediment of both sites suggest marginally
polluted sediment. According to Ontario’s provincial sediment quality guidelines, pollution can
range from clean/marginally polluted (‘lowest effect level’) at 600 mg/kg of phosphorus to
heavily contaminated (‘severe effect level’) at >2000 mg/kg of phosphorus in sediment (Ontario
MOE, 2008). Both the South Inlet and SW Cove have marginally polluted sediment, exceeding
the 600 mg/kg boundary by 60 mg/kg and 600 mg/kg, respectively. The decrease in total
phosphorus at the South Inlet site is promising as it is close to achieving the 600 mg/L boundary;
however, the continued increase in total phosphorus at SW Cove indicates an increase of
pollution over the past year into the lake.
Figure 16: Phosphorus concentrations in sediment samples from lake and stream sites sampled on September 28th, 2020.
0
200
400
600
800
1000
1200
1400
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
2018 2019 2020 Total Phosphorous (mg/kg)Orthophosphate (mg/kg)South Inlet
Total Phosphorus (P)Orthophosphate (P)
0
200
400
600
800
1000
1200
1400
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
2018 2019 2020 Total Phosphorous (mg/kg)Orthophosphate (mg/kg)SW Cove
Total Phosphorus (P)Orthophosphate (P)
a) b)
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3. Discussion
3.1. Algae Blooms in Fox Point Lake
There was one potential bloom sampled at FPL in 2020 however, the sample was lost in transit
from BV Labs to their contracted lab by UPS. The suspected bloom was associated with a large
flock of Canada geese (Branta canadensis) at the location therefore it is difficult to determine if
the water was discoloured due to a bloom or the geese.
Although no blooms were confirmed in 2020, FPL remains vulnerable to blooms in the future.
Chlorophyll α levels at all locations have increased since 2019. As algal blooms can be induced
and intensified by increases in nutrients to ecosystems (whether naturally from mixing of waters
or anthropogenically from pollution), trends in algal blooms are hard to predict and can vary
spatially. Increases in total nitrogen and phosphorus concentrations in FPL increase the potential
for blooms to occur. The literature predicts increases in both size and frequency of blooms,
globally, in the future (Michalak et al., 2013). Algal blooms should continue to be monitored and
tested within FPL, with residents made aware of algal bloom causes, health effects, precautions
to take, and the reporting procedure if a bloom occurs.
3.2. Trophic State of Fox Point Lake
Using various water parameters, the biological productivity of a lake can be assessed and
monitored for changes over time. Based on the mean depth of transparency (Secchi disk), and
mean concentrations of chlorophyll α and phosphorus, a Trophic State Index (TSI) score can be
calculated using the Carlson (1977) equations (Equations 1, 2, and 3) and averaging the results.
By calculating a TSI of a waterbody, the biological state (trophic state) of the water and how it
changes over time can be monitored. Trophic states range from oligotrophic (low productivity
and minimal biomass) to hypereutrophic (high productivity and maximum biomass).
Equation 1: 𝑆𝑆𝐼 (𝑆𝑐𝑐𝑐𝑖ℎ 𝑐�ℎ𝑟𝑘)=60 −14.41 × ln(𝑀𝑐𝑎𝑘 𝑆𝑐𝑐𝑐𝑖ℎ 𝑐�ℎ𝑟𝑘 [𝑘])
Equation 2: 𝑆𝑆𝐼 (𝑐�𝑘𝑘𝑟𝑘𝑘�𝑦𝑘𝑘 𝐴)=30.6 +9.81 × ln(𝑀𝑐𝑎𝑘 𝑐�𝑘𝑘𝑟𝑘𝑘�𝑦𝑘𝑘 𝑎 [𝜇𝑔
𝐿])
Equation 3: 𝑆𝑆𝐼 (𝑟𝑘𝑟𝑎𝑘 𝑘�𝑘𝑟𝑘�𝑘𝑟𝑟𝑟)=4.15 +14.42 × ln(𝑀𝑐𝑎𝑘 𝑟𝑘𝑟𝑎𝑘 𝑘�𝑘𝑟𝑘�𝑘𝑟𝑟𝑟 [𝜇𝑔
𝐿])
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Table 3: The results of the 2020 TSI calculations for the 3 associated water quality parameters.
Parameter Calculated TSI Value
Secchi (Transparency) 44.65
Chl α 48.90
Phosphorous 32.21
TSI Result 41.92
Figure 17: Carlson TSI for FPL using the mean Secchi disk depth (transparency), mean chlorophyll α concentration and mean total
phosphorus concentration within FPL in 2020. From Carlson, 1977.
For FPL, the trophic state has consistently been recorded as oligotrophic approaching
mesotrophic from 2015-2019, however the TSI results for 2020 put FPL into the mesotrophic
category (Figure 20). Phosphorus remains in the oligotrophic range however chlorophyll α
increased from a TSI of 38.9 in 2019 to 48.9 in 2020 putting it in the mesotrophic range
approaching eutrophic. Although the transparency via Secchi disk is not an exact indication of a
waterbody’s productivity due to interference by factors other than biomass (such as suspended
particles within the water column) (NSSA, 2014; United States Environmental Protection Agency
[US EPA], 2002), the continuing increase in chlorophyll a concentration over several years, and
despite the slight decrease in total phosphorus concentrations in the water, confirms this shift to
a mesotrophic state. The eutrophication process is driven initially by catchment processes that
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contribute excess nutrients, particularly phosphorus, to a waterbody and increases the
probability for the occurrence of cyanobacterial blooms (Necombe et al., 2010).
3.3. Potential for Nutrient Enrichment of Fox Point Lake
Excessive nutrients entering FPL can be detrimental to the health of the lake and will change the
lake’s trophic status. Nutrient enrichment can be from both external and internal loading
sources. External sources can be natural (wildlife waste, plant decomposition, etc.) or
anthropogenic (septic tank malfunction, fertilizer application, livestock waste, composter
leachate, etc.) (Sereda et al., 2008; Wetzel, 1990; Dion et al., 1983). Internal sources come from
within the lake, whether nutrients trapp ed within the lake substrate (i.e., orthophosphate) or
nutrients trapped in the water below the thermocline, and therefore unable to be mixed and
dispersed throughout the lake (Sondergaard et al., 2003; Kennedy and Walker, 1990).
Within FPL, external loading appears to affect the inlet streams more than the lake. Both inlet
streams had greater nitrogen and phosphorus concentrations compared to the lake.
Concentrations of nitrogen also increased within the two inlets following a rainfall even t. The
elevated nutrient concentrations of these two inlet streams suggests a level of pollution related
Figure 18: Comparison of FPL TSI scores from 2015 to 2020 and trophic states, using the Carlson (1977) trophic equations for
total phosphorus, chlorophyll α, and Secchi disk.
20
25
30
35
40
45
50
55
2015 2016 2017 2018 2019 2020TSI ValueSecchi TP Chla TSI
Oligotrophic
Mesotrophic
Eutrophic
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to nutrients, particularly phosphorus entering the South Inlet from nearby sources. Nutrient
loading within the two inlets is further increased during rainstorms via overland flow. Further
increases in nutrients from either stream may affect the delicate balance within the lake and
cause eutrophication.
Internal loading poses a risk to nutrient enrichment and eutrophication in FPL. Within the water
column, there are comparable nitrogen concentrations and an increase in phosphorus
concentrations below the thermocline compared to the surface waters (Table 4). When fall
turnover occurs, the redistribution of these elevated levels of nutrients results in a source of
internal loading and may cause eutrophication of the lake. Nutrients in sediments is an additional
internal loading source. Although orthophosphate makes up only 0.022% of total phosphorus in
the SW Cove sediment, the increase in total phosphorus concentrations (from 110 mg/kg to 1100
mg/kg) suggests an increase in pollution. In addition, the release of phosphorus from sediment
is not limited to lakes and can also occur in streams; the South Inlet’s marginally phosphorus-
polluted stream acts as an additional source of nutrients which may impact the lake.
Table 4: Nutrient concentrations from surface and depth waters (below the thermocline) within FPL, obtained on September 28th,
2019.
Surface Waters
2019 2020
At-Depth Waters
2019 2020
Phosphorus Concentrations (mg/L) 0.007 0.007 0.012 0.014
Nitrogen Concentrations (mg/L) 0.261 0.304 0.246 0.288
The development occurring along the South Inlet appears to be impacting nutrient enrichment
within FPL (Table 5) and warrants further investigation. The barn located on the property is used
to house animals, with their waste stored on site. As animal waste contains bacteria and
nutrients (Vanni, 2002), these can be flushed into the South Inlet and eventually the lake. During
the rainfall-only sampling event, a secondary South Inlet sample was collected, below this
residential property. Differences between nutrients from the two sites indicate that the
development is a source of nutrients for the South Inlet and lake. In addition, increases in both
phosphorus and orthophosphate concentrations at the SW Cove in the lake indicate enrichment
within the lake, potentially associated with development along the South Inlet (although it should
be noted that both phosphorus and orthophosphate concentrations increased at the upstream
South Inlet site as well, which is upstream of the residential property, Table 5). The addition of
nutrients into the South Inlet increases the potential for lake enrichment – especially after
rainfall, and possible eutrophication and algae blooms, as the presence of key nutrients stops
limiting the growth of organisms within the lake.
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Table 5: Nutrient concentrations from the two South Inlet sites following rainfall events in 2019 and 2020.
South Inlet
2019 2020
South Inlet Below Development
2019 2020
Difference
2019 2020
Phosphorus
Concentrations (mg/L)
0.049 0.065 0.049 0.056 0.000 - 0.009
Nitrogen
Concentrations (mg/L)
0.645 0.714 0.661 0.691 0.016 - 0.023
4. Recommendations
The following recommendations are suggested for the FPL Water Quality Monitoring Program,
based on the 2020 water quality results:
• The FPL Water Quality Monitoring Program should continue in 2021.
o The program should continue to collect monthly water samples from all four sites.
o Due to the high nutrients and bacteria measured at the second South Inlet site,
consideration should be given to adding the secondary site to the monthly
sampling program or retain the site for continued rainfall-dependent sampling.
o The program should continue to obtain one-time sediment samples from the SW
Cove and South Inlet, as arsenic and mercury may pose a risk to aquatic organisms’
health and should be monitored.
o One-time lake water samples from below the thermocline should continue to be
monitored to assess the risk associated with internal loading and potential late-
season algal blooms.
o The program should continue to supply FPL volunteers with certified bottles to
sample and test for the presence of microcystins-LR during future algal blooms.
• Should MOC and the Municipality of the District of Lunenburg choose to purchase a
ProDSS Total Algae PC Sensor for the municipally owned YSI unit, monitoring of the SW
Cove and the North Inlet for Chl α and phycocyanin (the pigment associated with blue
green algae) should be added to the monitoring of the lake.
• Due to the expected increases in droughts and rainfall events associated with climate
change, the one-time, rainfall-dependent sampling event should continue to be included
in the FPL Water Quality Monitoring Program.
• Continued observing of the weather station and staff gauge to monitor temperature,
precipitation, and lake water levels throughout the sampling program.
• As the FPL Water Quality Monitoring Program has been ongoing since 2015 , a trend report
should be added to the 2021 program to summarize any long-term trends observed on
the lake.
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5. References
Beanlands, D.I. 1980. Surveys of Ten Lakes in Guysborough, Halifax, Hants, and Lunenburg
Counties, Nova Scotia, 1978. Freshwater and Anadromous Division Resource Branch.
Canadian Data Report of Fisheries and Aquatic Sciences No. 192.
Brylinsky, M. (2004). User’s Manual for Prediction of Phosphorus Concentration in Nova Scotia
Lakes: A Tool for Decision Making. Version 1.0. Acadia Centre for Estuarine Research, Acadia
University. 82 p.
Canadian Council of Ministers of the Environment (CCME). (1999). Canadian water quality
guidelines for the protection of aquatic life: Dissolved oxygen (Freshwater). In: Canadian
environmental quality guidelines, 1999, Canadian Council of Ministers of the Environment,
Winnipeg.
Canadian Council of Ministers of the Environment (CCME). (2001). Canadian sediment quality
guidelines for the protection of aquatic life: Introduction. Updated. In: Canadian
environmental quality guidelines, 1999, Canadian Council of Ministers of the Environment,
Winnipeg.
Canadian Council of Ministers of the Environment (CCME). 2002. Canadian water
quality guidelines for the protection of aquatic life: Total particulate matter. In:
Canadian environmental quality guidelines, 1999, Canadian Council of Ministers of
the Environment, Winnipeg.
Carlson, R. E. (1977). A trophic state index for lakes. Limnology and oceanography, 22(2), 361-
369.
Dion, N. P., Sumioka, S. S., and Winter, T. C. (1983). General hydrology and external sources of
nutrients affecting Pine Lake, King County, Washington. US Department of the Interior, US
Geological Survey.
Dodds, W.K. and Welch, E.B. (2000). Establishing nutrient criteria in streams.
J.N.Am.Benthol.Soc.19(1), 186-196.
Health Canada. (2012). Guidelines for Canadian Recreational Water Quality, Third Edition. Water
Air, and Climate Change Bureau, Healthy Environments and Consumer Safety Branch, Health
Canada, Ottawa, Ontario. (Catalogue No H129-15/2012E).
Hinch, P.R. and Underwood, J.K. 1985. A study of aquatic conditions in Lake Echo durin g
1984. N.S. Dept. Env. Lib. L192.1 85/00 C2. 38 p.
Kennedy, R. H., and Walker, W. W. (1990). Reservoir nutrient dynamics. Reservoir limnology:
ecological perspectives, 109-131.
Mackie, G. 2004. Applied Aquatic Ecosystem Concepts. 2d ed. Dubuque, Iowa.
Kendall/Hunt Publishing Company.
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Page | 32
Michalak, A.M., Anderson, E.J., Beletsky, D., Boland, S., Bosch, N.S., Bridgeman, T.B., Chaffin, J.D.,
Cho, K., Confesor, R., Daloğlu, I. and DePinto, J.V. (2013). Record-setting algal bloom in Lake
Erie caused by agricultural and meteorological trends consistent with expected future
conditions. Proceedings of the National Academy of Sciences, 201216006.
Necombe, G., House, J., House, Ho, L., Baker P. and Burch M. (2010). Management Strategies for
Cyanobacteria (Blue-Green Algae): A Guide for Water Utilities. Research Report No. 74. Water
Quality Research Australia.
Nova Scotia Environment (NSE). (2014). Environmental Quality Standards for Contaminated Sites,
Rationale and Guidance Document. Version 1.0, April 2014. 57 p.
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