HomeMy Public PortalAboutFoxPoint Lake Water Quality Monitoring Report 2022
Fox Point Lake 2022 Water Quality Monitoring Report
Kaylee MacLeod
Blake McNeely
February 2023
Prepared for:
Municipality of Chester
Fox Point Lake Water Quality Monitoring Committee
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Fox Point Lake 2022 Water Quality Monitoring Report
Contributing Authors:
Kaylee MacLeod, MSc, Watersheds & Water Quality Project Coordinator
Blake McNeely, BA, Watersheds & Water Quality Team Lead
February 2023
Coastal Action
45 School Street, Suite 403
Mahone Bay, N.S., B0J 2E0
Ph: (902) 634-9977
Email: info@coastalaction.org
Correct citation for this publication:
MacLeod, K. & McNeely, B. (2023). Fox Point Lake 2022 Water Quality Monitoring Report.
Mahone Bay, Nova Scotia.
This work was supported by:
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Table of Contents
List of Figures ........................................................................................................................................................ iii
List of Tables ........................................................................................................................................................... v
1.0 Introduction ..................................................................................................................................................... 1
1.1 Fox Point Lake Background ................................................................................................................... 1
1.2 Program Background ............................................................................................................................... 2
1.3 Review of the 2021 Fox Point Lake Water Quality Monitoring Report ................................ 2
2.0 Water Quality Monitoring Results .......................................................................................................... 4
2.1 Physical Water Quality Parameters ................................................................................................... 4
2.1.1 Chlorophyll-α and Phycocyanin ................................................................................................... 4
2.1.2 Stream Discharge............................................................................................................................... 5
2.1.2 Water Temperature and Stratification of Fox Point Lake ................................................. 7
2.1.3 Dissolved Oxygen and Stratification of Fox Point Lake ...................................................... 8
2.1.4 pH ......................................................................................................................................................... 11
2.1.5 Total Dissolved Solids ................................................................................................................... 11
2.2 Chemical Water Quality Parameters ............................................................................................... 12
2.2.1 Total Suspended Solids ................................................................................................................ 12
2.2.2 Total Phosphorus ........................................................................................................................... 13
2.2.3 Total Nitrogen .................................................................................................................................. 15
2.3 Biological Water Quality Parameters ............................................................................................. 17
2.3.1 Fecal Bacteria ................................................................................................................................... 17
2.3.2 Microcystins and Algal Blooms ................................................................................................. 18
3.0 Sediment Sampling .................................................................................................................................... 18
3.1 Metals .......................................................................................................................................................... 18
3.2 Phosphorus ............................................................................................................................................... 21
4.0 Discussion ...................................................................................................................................................... 22
4.1 Algae Blooms in Fox Point Lake ........................................................................................................ 22
4.3 Trophic State of Fox Point Lake ........................................................................................................ 23
4.4 Potential for Nutrient Enrichment of Fox Point Lake .............................................................. 25
5.0 Recommendations ...................................................................................................................................... 27
6.0 References ..................................................................................................................................................... 28
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List of Figures
Figure 1. Drainage basin and sampling sites of Fox Point Lake. ......................................................... 1
Figure 2. Phycocyanin (cells/mL) levels from the 2022 monthly sampling events at the lake
sites. The WHO provides two guidelines; Alert level 1 at 20,000 cells/mL, and Alert level 2
at 100,000 cells/mL. ............................................................................................................................................ 5
Figure 3. 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. ................................................................................................................................... 6
Figure 4. Mean (blue line) stream discharge rates from June to October 2016 to 2022 for
comparison. The maximum and minimum ranges of stream discharge are designated by the
grey area. .................................................................................................................................................................. 6
Figure 5. Monthly water temperature from the lake and three stream sites at FPL from
June-October 2022. The red line indicates the 20oC water temperature threshold for cold-
water fish species. ................................................................................................................................................. 7
Figure 6. Monthly water temperature depth profiles from the lake site at FPL from June-
October 2022. The red line indicates the 20oC water temperature threshold for cold-water
fish species. .............................................................................................................................................................. 8
Figure 7. Monthly DO from the lake and three stream sites at FPL from June-October 2022.
The red line indicates the 6.5 mg/L DO minimum for aquatic organisms as set by the CCME.
...................................................................................................................................................................................... 9
Figure 8. Monthly dissolved oxygen depth profiles from the lake site at FPL from June-
October 2022. The red line indicates the 6.5 mg/L DO minimum for aquatic organisms, as
set by the CCME. ................................................................................................................................................. 10
Figure 9. Monthly pH from the lake and three stream sites at FPL from June-October 2022.
The solid red line indicates the 6.5 pH threshold set by CCME, and the dotted red line
indicates the 5.0 pH threshold identified by NSSA. .............................................................................. 11
Figure 10. Monthly total dissolved solids from the lake and three stream sites at FPL from
June-October 2022. ........................................................................................................................................... 12
Figure 11. Monthly total suspended solids from the lake and three stream sites at FPL from
June-October 2022. ........................................................................................................................................... 13
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Figure 12. Monthly total phosphorus concentrations from the lake, three stream sites and
south culvert site at FPL from June-October 2022. 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. ............................................................................................................................ 14
Figure 13. Average total phosphorus concentrations from June-October from 2016 to 2022
for comparison. The 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. .. 15
Figure 14. Monthly total nitrogen concentrations from the lake and three stream sites at
FPL from June-October 2022. The red line indicates the 0.9 mg/L guideline for freshwater
environments, as set by Dodds and Welch (2000). .............................................................................. 16
Figure 15. Average nitrogen concentrations from June-October 2015 to 2022 for
comparison. .......................................................................................................................................................... 16
Figure 16. Monthly fecal bacteria concentrations from the lake and the three stream sites at
FPL from June-October 2022. ........................................................................................................................ 17
Figure 17. Phosphorus concentrations in sediment samples from lake and stream sites
2018 – 2022 for comparison. Total phosphorus was not included in the 2021 samples and
only the SW Cove site was sampled in 2022. .......................................................................................... 22
Figure 18: Carlson TSI for FPL using the mean Secchi disk depth (transparency), mean
chlorophyll-α concentration and mean total phosphorus concentration within FPL in 2022.
From Carlson, 1977. .......................................................................................................................................... 24
Figure 19. Comparison of FPL TSI scores from 2015 to 2022 and trophic states, using the
Carlson (1977) trophic equations for total phosphorus (TP), chlorophyll-α (Chla), and
Secchi disk (Secchi). .......................................................................................................................................... 25
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List of Tables
Table 1: Concentration of metals within site sediment samples. Light yellow indicates
parameters approaching one of the guidelines, orange indicates an exceedance of ISQG, and
red indicates an exceedance of either the PEL or NSEQS guidelines. ............................................ 18
Table 2: Summary of three years of guideline exceedances of metals in sediment samples
from SW Cove and South Inlet sampling locations. .............................................................................. 21
Table 3: The results of the 2022 TSI calculations for the 3 associated water quality
parameters. Secchi depth was not taken in June, so that parameter is missing from this
calculation. ............................................................................................................................................................ 24
Table 4: Nutrient concentrations from surface and at-depth waters (below the thermocline)
within FPL. ............................................................................................................................................................ 26
Table 5: Nutrient concentrations of total phosphorus (TP) and total nitrogen (TN) from the
two South Inlet sites following rainfall events from 2019 - 2022. ................................................. 27
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Executive Summary
This report outlines the activities and results of the 2022 Fox Point Lake (FPL) water quality
monitoring program. This project began as a result of water quality concerns from residents
after sedimentation events occurred in the lake following the development of the Aspotogan
Ridge Golf Course.
In June, August, September and October 2022, volunteers and Coastal Action staff collected
water samples at one lake site and three stream sites (an outlet and two inlets). On
September 28, 2022 volunteers and staff collected samples for the rainfall event. Sediment
samples were also taken at the South West (SW) Cove. An at-depth sample, taken below the
thermocline at the lake site, was analyzed for total phosphorus and total nitrogen.
Factors measuring or contributing to the production of algae in freshwater, including
phycocyanin, total phosphorus and total nitrogen, did not exceed guidelines set by the World
Health Organization or Ontario’s Ministry of Environment and Climate Change guidelines,
except for the North Inlet, South Inlet and South Culvert which exceeded the threshold of
0.03 mg/L for total phosphorus in rivers and streams at least once in 2022.
Surface water temperatures of all sites, except the South Inlet, exceeded or approached the
20oC temperature threshold for cold-water fish species (NSSA 2014) during August.
Dissolved oxygen at the lake site stayed above the minimum threshold of 6.5 mg/L set by the
Canadian Council of Ministers of the Environment (CCME) for cold -water species (CCME
1999). Some of the stream sites were below this threshold in June, August and October.
pH measurements for all sites fell below, or just above the 6.5-pH threshold set by the CCME
(2002); however, the acidity of FPL waters is not uncommon for southwest NS lakes, which
generally have lower pH values than the 6.5 threshold. It appears that most of the time, the
acidity of the waters at FPL poses minimal threat to organisms.
E. coli levels at all sites did not exceed or approach recreational guidelines. Despite a spike
in levels following the rainfall in October, levels remained below the threshold and returned
to 20 CFU/100 mL or less four days later.
In the sediment sample from the SW Cove site, arsenic and cadmium exceeded the CCME’s
recommended interim sediment quality guidelines (ISQG), while mercury and selenium
approached the ISQG and Nova Scotia Environmental Quality Standards (NSEQS)
contamination threshold, respectively.
Based on the mean depth of transparency (Secchi disk), and mean concentrations of
chlorophyll-α and phosphorus, a Trophic State Index (TSI) score has been calculated
annually to assess biological productivity. Trophic states range from oligotrophic (low
productivity and minimal biomass) to hypereutrophic (high productivity and maximum
biomass). The trophic state of FPL in 2015-2019 and 2021 was oligotrophic approaching
mesotrophic, while the 2022 TSI results categorize the lake as mesotrophic.
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Within FPL, it appears that external loading of nutrients is affecting the inlet streams more
than the lake. Both inlet streams had greater nitrogen and phosphorus concentrations
compared to the lake.
Recommendations for next steps in Fox Point Lake include using a Sand Wand to remove fine
sediment embedded in the Sout Inlet to improve aquatic habitat quality. This would improve
the stream habitat for both fish and benthic macro-invertebrates, as well as stream flow.
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1.0 Introduction
The following report summarizes the results from the 2022 monitoring period at Fox Point
Lake (FPL). Sample events occurred in June, August, September and October. Samples were
not taken in July, therefore the sampling was extended to October according to volunteer
availability. A rainfall sample was also taken in October.
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 (MOC) created the Fox Point Lake Water Quality Monitoring Committee (WQMC).
With 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 2015-2021; all are available on request from the Municipality of
Chester.
1.3 Review of the 2021 Fox Point Lake Water Quality Monitoring Report
The 2021 report included data from 2021, as well as a review of water quality changes at the
lake from 2015 to 2021.
The trophic state of FPL was determined to be oligotrophic and approaching mesotrophic
during each sampling year from 2015 through 2019, in 2020 the lake was mesotrophic but
returned to oligotrophic in 2021. The increase in chlorophyll-α concentrations suggests the
lake may return to the mesotrophic range in future years.
Thermal stratification was observed at the lake sample site, while dissolved oxygen (DO)
indicated a depletion of oxygen at depth, with concentrations below 3 mg/L recorded in the
bottom waters of the lake. 2021 had some of the highest temperatures and lowest DO
concentrations of the previous seven years of the study. In all years of the project, the top
four meters of the lake exceeded the 20°C threshold, required for cold-water species.
In 2021 there were two blooms observed in the lake by volunteers. The first bloom occurred
on July 17th, 2021. Results showed no Microcystin-LR present in the sample. The second
bloom was detected by volunteers on August 29th, 2021. Results showed a Microcystin-LR
concentration of 0.13 µg/L. Blooms were also reported and sampled in 2016, 2017, and 2018
which all confirmed the presence of Microcystin-LR. Blooms were also reported in 2019 and
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2020; however, Nova Scotia Environment visited the site in 2019 but no bloom was present,
and the 2020 sample was lost in transit by UPS.
Total phosphorus levels have remained below phosphorus guidelines for most years at the
lake, north inlet, and outlet. The South Inlet site exceeded the 0.03 mg/L MOECC stream
guideline as it has done from 2015-2021; however, it has been slowly improving despite a
slight increase from 2020 to 2021. The south culvert has also exceeded phosphorus
guidelines in the three previous years it was sampled.
Sediment has been sampled at the Southwest Cove (SWC) and South Inlet (SI) sites since
2017 to test for metal concentrations. At the SWC site, arsenic, cadmium, lead, and mercury
exceed or approach ISQG guidelines. At the SWC site, selenium exceeded NSE guidelines each
year. For the SI site, mercury exceeded ISQG from 2018 to 2021 and approached the
guideline in 2017; while lead levels have decreased and are no longer approaching the
guideline. At the SI site, arsenic exceeded NSE guidelines in 2019 and 2021 and exceeded
ISQG in the other years.
Rainfall was monitored by a volunteer using a rain gauge, then a weather station was
installed at the lake in 2021. In 2021, the weather station was used to remotely collect 107
readings, totalling 607 mm of rain.
Water levels of the lake (monitored by a volunteer using a staff gauge), remained consistent
from 2015 to 2021. Stream discharge rates were highest in 2019 and lowest in 2016, which
corresponds with observed rainfall amounts.
The trophic state index (TSI) of FPL has consistently been recorded as oligotrophic
approaching mesotrophic from 2015-2019; however, the TSI results for 2020 put FPL into
the mesotrophic category. The trophic state returned to oligotrophic in 2021. An increasing
rate of chlorophyll-α concentrations suggests the lake may return to the mesotrophic range
in future years.
Water quality data from the North Inlet over the last seven years shows that almost every
parameter is rising, except total suspended solids and bacteria which are slightly declining.
The stream is becoming more nutrient-rich, with both the temperature and pH increasing.
The South Inlet has had varied changes in each parameter. Temperature, dissolved oxygen,
total dissolved solids, and total suspended solids are on the rise, while total phosphorus, total
nitrogen and bacteria are declining.
Water quality parameters for the outlet are all on the rise, except nitrogen which has had a
slight downward trend throughout the project.
The water quality data from the Lake site show varied changes in every parameter. Dissolved
oxygen, pH, total dissolved solids, total nitrogen, and chlorophyll -α are on the rise.
Temperature, total suspended solids, total phosphorous, and bacteria are declining.
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2.0 Water Quality Monitoring Results
2.1 Physical Water Quality Parameters
2.1.1 Chlorophyll-α and Phycocyanin
In 2021, a ProDSS Total Algae PC Sensor was purchased by MODL to use on the ProDSS YSI
unit owned jointly by MOC and MODL. This probe measures concentrations of chlorophyll-α
and phycocyanin present in water. Phycocyanin is a pigment found in cyanobacteria, or blue-
green algae, and provides an estimate of total cyanobacteria production. Chlorophyll -α is a
pigment produced by all types of algae and provides an estimate of total algae production.
Collecting this data over multiple seasons will provide baseline concentrations of
phycocyanin in Fox Point Lake, which can vary across waterbodies. Long-term monitoring
with this probe, paired with the collection of Microcystin -LR water samples during blooms,
will help to identify spikes in phycocyanin concentrations and build a predictive curve for
the relationship between the concentrations of these algal pigments and the occurrence of
algal blooms in FPL.
Algal concentrations are measured as Relative Fluorescence Units (RFU). Phycocyanin RFU
units were converted to the total number of cells (Genzoli and Kann 2016). World Health
Organization (WHO) provides two guideline levels, ‘alert level 1’ is reached when 20,000
phycocyanin cells/mL are observed, and ‘alert level 2’ is reached when 100,000 phycocyanin
cells/mL are observed. At no point were the WHO guidelines exceeded or approached
(Figure 2). The data were not collected before, during, or immediately after any known algae
blooms.
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Figure 2. Phycocyanin (cells/mL) levels from the 2022 monthly sampling events at the lake sites . The WHO provides two
guidelines; Alert level 1 at 20,000 cells/mL, and Alert level 2 at 100,000 cells/mL.
2.1.2 Stream Discharge
Stream discharge rates were monitored at the two inlet sites and the outlet site monthly from
June to October 2022. 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.
Rainfall data was taken from the Environment Canada historical database for June through
October 2022 from the weather station in Halifax (Figure 3).
The South Inlet had the lowest and most consistent flow throughout the sampling period,
while the North Inlet had a slightly greater discharge in October which corresponds to the
rainfall events (Figure 3). The discharge from the Outlet was variable throughout the
sampling period.
Overall, the rate of discharge had increasing variability at both the South and North Inlet
sites from 2018 to 2020, which decreased at both sites from 2021 to 2022 (Figure 4). The
outlet has remained relatively stable.
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Figure 3. 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 4. Mean (blue line) stream discharge rates from June to October 2016 to 2022 for comparison. The maximum and
minimum ranges of stream discharge are designated by the grey area.
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2.1.2 Water Temperature and Stratification of Fox Point Lake
Water temperatures from the four FPL sites were recorded monthly during the 2022
program; temperatures ranged from 11.2°C to 23.9°C (Figure 5). The South Inlet was
consistently cooler than the other sites throughout the sampling period. The highest
temperature recorded was at the Lake site in August.
The Lake and Outlet sites exceeded the 20oC temperature threshold for cold-water fish
species (Nova Scotia Salmon Association [NSSA] 2014) in June and August. In August, the
only site that did not exceed the threshold was the South Inlet. 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.
Figure 5. Monthly water temperature from the lake and three stream sites at FPL from June-October 2022. The red line
indicates the 20oC water temperature threshold for cold-water fish species.
A monthly water profile was also constructed from within the lake during the 2022 sampling
period (Figure 6). 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 cooler, more-dense waters settling to the lake bottom (hypolimnion). The
thermocline, the depth at which the water temperature rapidly changes, is located at 7-m
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water depth in June. Although the surface waters of the lake exceeded the 20oC threshold for
cold-water fish in June and August, temperatures were below the threshold in deeper waters.
Due to the density differences between the epilimnion and hypolimnion, little mixing occurs
within the thermally stratified parts of the lake. September and October had consistent
temperatures at all depths, suggesting fall turnover (when the lack of stratification
encourages mixing of the waters at all depths of the lake) occurred before the September
sampling event.
Figure 6. Monthly water temperature depth profiles from the lake site at FPL from June-October 2022. The red line indicates
the 20oC water temperature threshold for cold-water fish species.
2.1.3 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 2022 (Figure 7). DO ranged from 2.37 mg/L to 9.98 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 the lack of turbulence of the water.
The low DO in the North Inlet may negatively affect aquatic organisms. DO is a requirement
for the survival of aquatic organisms, with a minimum threshold of 6.5 mg/L set by the
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Canadian Council of Ministers of the Environment (CCME) for cold-water species (CCME
1999). Each site, except the lake, had at least one instance of levels below the threshold
during the sampling season. The North Inlet was consistently below the threshold except for
the September sample and rainfall event in October. The South Inlet and Outlet each had
values lower than 6.5 mg/L in August (5.94 mg/L and 5.04 mg/L, respectively). Although fish
can survive in low-DO environments for short periods, the low-DO environment in the North
Inlet may be causing physiological stress to fish in that stream.
The low-DO concentrations in the North Inlet are consistent with previous years. The
reduction in DO during the summer is a consistent annual trend due to the decreased ability
of warmer waters to dissolve oxygen and the higher DO demand during the growing season,
leaving the Lake the only refuge during August.
Figure 7. Monthly DO from the lake and three stream sites at FPL from June-October 2022. The red line indicates the 6.5 mg/L
DO minimum for aquatic organisms as set by the CCME.
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 October and the
rainfall event. 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, results in the decline in DO concentrations in the hypolimnion until
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the water column mixes again during fall turnover (Smith and Bella 1973). By September,
fall cooling and mixing had begun bringing DO deeper into the water column with the
stratification extending to a 12-m water depth.
The DO depth profile within the lake appears to be a clinograde curve, with a negative
heterograde curve occurring in August. 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 primarily in June 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 August (Figure 8). A negative heterograde
curve has also been confirmed in previous years in FPL.
Figure 8. Monthly dissolved oxygen depth profiles from the lake site at FPL from June-October 2022. The 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
August, the hypolimnion’s DO concentrations fell below 6.5 mg/L. The decline in DO
concentrations below the CCME threshold occurs at 14 m for June and becomes hypoxic (<2
mg/L) below 15 m. No other months reached hypoxic or anoxic conditions (<1 mg/L). The
low dissolved oxygen conditions observed in late summer can reduce the ability to support
aquatic life (United States Geological Survey [USGS] 2014; Brylinsky 2004).
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2.1.4 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 appears that most of the time (save for the low sub-5.0 pH measurements in the
North Inlet and South Inlet, in June and October) the acidity of the waters at FPL pose
minimal threat to organisms.
Figure 9. Monthly pH from the lake and three stream sites at FPL from June-October 2022. The solid red line indicates the 6.5
pH threshold set by CCME, and the dotted red line indicates the 5.0 pH threshold identified by NSSA.
2.1.5 Total Dissolved Solids
Total dissolved solids (TDS) from the four FPL sites sampled monthly from June-October
2022 ranged from 22 mg/L to 53 mg/L (Figure 10). The highest TDS concentrations were
consistently measured within the North Inlet, while the remaining three sites never
exceeded 35 mg/L.
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Although TDS concentrations within FPL are higher than in 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 28.6 mg/L in 2022, suggesting that the lake is not pristine
and to some extent affected by sedimentation. 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 10. Monthly total dissolved solids from the lake and three stream sites at FPL from June-October 2022.
2.2 Chemical Water Quality Parameters
2.2.1 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 fibre filter. For FPL, TSS ranged from <1
mg/L to 12 mg/L, which is the greatest range of TSS values seen throughout this project
(Figure 11). The North Inlet had the highest TSS levels of all sites in June and August but was
below detection levels in September and the rainfall event. The TSS at the Lake site has
remained low for 2022 with a mean concentration of 1.36 mg/L, well below the average 3.0
0
10
20
30
40
50
60
1-Jun-22 1-Jul-22 1-Aug-22 31-Aug-22 1-Oct-22 31-Oct-22
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North Inlet South Inlet Lake Outlet South Culvert
13
mg/L background concentration of Nova Scotia lakes reported 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 11. Monthly total suspended solids from the lake and three stream sites at FPL from June-October 2022.
2.2.2 Total Phosphorus
Total phosphorus within FPL, monitored and analyzed at BV Labs monthly from June to
October 2022, ranged from 0.004 mg/L to 0.085 mg/L (Figure 12). 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 0.01 mg/L.
Ontario’s Ministry of Environment and Climate Change (MOECC) has established two
guidelines 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 consistently exceed the phosphorus guidelines for streams in 2022 as well as the
South Culvert site. The North Inlet was 0.03 mg/L during the June sample and exceeded the
guideline in August. The phosphorus concentrations of the lake and Outlet sites never
exceeded 0.01 mg/L.
0
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4
6
8
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12
14
1-Jun-22 1-Jul-22 1-Aug-22 31-Aug-22 1-Oct-22 31-Oct-22
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North Inlet South Inlet Lake Outlet South Culvert
14
As mentioned above, the South Inlet site exceeded the 0.03 mg/L MOECC stream guideline
for phosphorus during the entire 2022 sampling season. This sample site has exceeded the
MOECC stream guideline for phosphorus for each sample obtained throughout this project
(2015-2022). 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 decreasing over the past seven years (Figure
13). Other sites have maintained relatively consistent total phosphorus levels, except for the
North Inlet, which appears to have had a slight increase from 2020 to 2022. 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.
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
8-Jun-22 28-Jun-22 18-Jul-22 7-Aug-22 27-Aug-22 16-Sep-22 6-Oct-22 26-Oct-22 15-Nov-22
To
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North Inlet South Inlet Lake Outlet South Culvert At-depth
Figure 12. Monthly total phosphorus concentrations from the lake, three stream sites and south culvert site at FPL from June -
October 2022. 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.
15
Figure 13. Average total phosphorus concentrations from June-October from 2016 to 2022 for comparison. The 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.
2.2.3 Total Nitrogen
Total nitrogen analysis was performed by BV Labs monthly from June to October 2022 for
all four FPL sites along with the one South Culvert sample (Figure 14). Total nitrogen ranged
from 0.198 mg/L to 0.871 mg/L; the highest nitrogen concentration was recorded at the
South Inlet. The nitrogen concentration obtained at depth, below the thermocline in the lake,
was 0.389 mg/L.
Overall, the nitrogen levels in the lake and outlet have remained consistent since 2016
(Figure 15), while there is an overall slight increase at the South Inlet, North Inlet, and South
Culvert sites.
0.000
0.020
0.040
0.060
0.080
0.100
0.120
0.140
0.160
0.180
2015 2016 2017 2018 2019 2020 2021 2022
Av
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)
Year
North Inlet South Inlet Lake Outlet South Culvert
16
Figure 14. Monthly total nitrogen concentrations from the lake and three stream sites at FPL from June-October 2022. The
red line indicates the 0.9 mg/L guideline for freshwater environments, as set by Dodds and Welch (2000).
Figure 15. Average nitrogen concentrations from June-October 2015 to 2022 for comparison.
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
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1-Jun-22 1-Jul-22 1-Aug-22 31-Aug-22 1-Oct-22 31-Oct-22
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North Inlet South Inlet Lake Outlet South Culvert At-depth
0.000
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0.400
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2015 2016 2017 2018 2019 2020 2021 2022
Av
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North Inlet South Inlet Lake Outlet South Culvert
17
2.3 Biological Water Quality Parameters
2.3.1 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 2022 field
season (Figure 16). Samples ranged from 2 CFU/100 mL to 160 CFU/100 mL. The North Inlet
had the highest E. coli concentration observed in 2022, during the October rainfall sampling
event (160 CFU/100 mL). The Lake site had a mean of 10.8 CFU/100 mL throughout the
sampling period.
During the rainfall-dependent sampling event, bacteria concentrations spiked in the North
Inlet, South Inlet, and South Culvert. All other sites also had an increase in bacteria
concentrations after the rainfall event; however, levels returned to 20 CFU/100 mL or less
at all sites four days after the rainfall.
Figure 16. Monthly fecal bacteria concentrations from the lake and the three stream sites at FPL from June-October 2022.
0
20
40
60
80
100
120
140
160
180
1-Jun-22 1-Jul-22 1-Aug-22 31-Aug-22 1-Oct-22 31-Oct-22
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North Inlet South Inlet Lake Outlet South Culvert
18
2.3.2 Microcystins and Algal Blooms
The recreational guideline for cyanobacterial toxins – Microcystin-LR is 10 µg/L (Health
Canada 2012). This guideline is meant to protect against exposure to microcystins and other
toxins that may be present in an algal bloom. Microcystin-LR can persist in aquatic
environments after a visible bloom has dissipated (Jones and Orr 1994).
Not all algal blooms are toxic cyanobacteria blooms, and Microcystin-LR is only one of the
possible toxins in a cyanobacteria bloom. For this reason, every algal bloom should be
treated with caution and reported to Nova Scotia Environment (NSE). There were no reports
of algae blooms in 2022. There were concerns about substances that looked like a bloom;
however, this was not confirmed and no tests were performed.
3.0 Sediment Sampling
Sediment sampling from the Southwest side of the lake (known as ‘SW Cove’) occurred on
September 28th, 2022. Due to a sampling error, no sample was taken from the South Inlet in
2022. The substrate was analyzed for metals, phosphorus, and orthophosphate, to assess the
risk of internal nutrient loading within the lake and the potential risk from the accumulation
of metals within the sediments (Tables 1 & 2).
3.1 Metals
Table 1: Concentration of metals within site sediment samples. Light yellow indicates parameters approaching one of the
guidelines, orange indicates an exceedance of ISQG, and red indicates an exceedance of either the PEL or NSEQS guidelines.
Sediment Concentration
Guidelines
Metals UNITS
SW Cove
ISQG PEL NS
2022
Acid Extractable Aluminum (Al) mg/kg 6400
Acid Extractable Antimony (Sb) mg/kg ND 25
Acid Extractable Arsenic (As) mg/kg 8 5.9 17 17
Acid Extractable Barium (Ba) mg/kg 35
19
Acid Extractable Beryllium (Be) mg/kg 1.6
Acid Extractable Bismuth (Bi) mg/kg ND
Acid Extractable Boron (B) mg/kg ND
Acid Extractable Cadmium (Cd) mg/kg 0.63 0.6 3.5 3.5
Acid Extractable Chromium (Cr) mg/kg 3.2 37.3 90 90
Acid Extractable Cobalt (Co) mg/kg 1.1
Acid Extractable Copper (Cu) mg/kg 5.7 35.7 197 197
Acid Extractable Iron (Fe) mg/kg 2900 47,766
Acid Extractable Lead (Pb) mg/kg 9 35 91.3 91.3
Acid Extractable Lithium (Li) mg/kg 5.8
Acid Extractable Manganese (Mn) mg/kg 160 1,100
Acid Extractable Mercury (Hg) mg/kg 0.14 0.17 0.486 0.486
Acid Extractable Molybdenum (Mo) mg/kg ND
Acid Extractable Nickel (Ni) mg/kg 2.2 75
Acid Extractable Phosphorus (P) mg/kg 510
Acid Extractable Rubidium (Rb) mg/kg 5.2
Acid Extractable Selenium (Se) mg/kg 1.7 2
Acid Extractable Silver (Ag) mg/kg ND 1
Acid Extractable Strontium (Sr) mg/kg 13
Acid Extractable Thallium (Tl) mg/kg ND
Acid Extractable Tin (Sn) mg/kg 1.1
20
Acid Extractable Uranium (U) mg/kg 10
Acid Extractable Vanadium (V) mg/kg 6.9
Acid Extractable Zinc (Zn) mg/kg 31 123 315 315
Orthophosphate (P) mg/kg 0.47
ND = Not Detected
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 2022 at SW Cove indicate that arsenic and cadmium exceeded the
ISQG guidelines. Mercury and selenium were approaching ISQG and NSEQS guidelines,
respectively (CCME 2001; NSE 2014). Arsenic, cadmium, lead, and selenium were lower than
2021 levels (Table 2). Mercury levels increased by 0.1 mg/kg in 2022. Selenium, which
exceeded the NS guidelines last year, fell below the threshold in 2022.
21
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 Guidelines
UNIT
S 2018 2019 2020 2021 2022 2017 2018 2019 2020 2021 ISQG PEL NS
Acid
Extractable
Arsenic (As)
mg/k
g 6 6.1 9.1 20 8 7.9 10 22 9.8 35 5.9 17 17
Acid
Extractable
Cadmium (Cd)
mg/k
g ND 0.8 0.48 1.6 0.63 ND 0.4 0.37 ND ND 0.6 3.5 3.5
Acid
Extractable
Lead (Pb)
mg/k
g 2.6 50 61 21 9 17 33 31 21 21 35 91.3 91.3
Acid
Extractable
Mercury (Hg)
mg/k
g ND 0.16 0.23 0.13 0.14 0.12 0.21 0.17 0.17 0.19 0.17 0.48
6
0.48
6
Acid
Extractable
Selenium (Se)
mg/k
g ND 2.7 2.1 3.3 1.7 ND 1.1 1 0.71 0.9 2
3.2 Phosphorus
Concentrations of both acid-extractable (total) phosphorus and bioavailable orthophosphate
were analyzed within the sediment substrate from SW Cove. Within SW Cove, the
concentration of orthophosphate was 0.16 mg/kg in 2021 and increased to 0.47 mg/kg in
2022 (0.09% of total phosphorus concentrations) (Figure 17).
22
Figure 17. Phosphorus concentrations in sediment samples from lake and stream sites 2018 – 2022 for comparison. Total
phosphorus was not included in the 2021 samples and only the SW Cove site was sampled in 2022.
There was an increase in bioavailable phosphorus, despite a decrease in total phosphorus
from 2020 to 2022. This 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 from both the SW Cove and South Inlet sites suggest
marginally polluted sediment from 2019 to 2020. 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). The decrease in total phosphorus at the SW
Cove site in 2022, results in levels below the 600 mg/kg boundary.
4.0 Discussion
4.1 Algae Blooms in Fox Point Lake
There were no reported algae blooms in 2022 at Fox Point Lake.
NS Environment’s current system of notifying lake residents of potentially harmful algae
blooms is reactive and can be ineffective. NSE responds to reports of suspected blooms but
inspectors are not always able to respond in time to witness the bloom. NSE rarely collects
water samples for analysis and often has to post precautionary advisories based on the
appearance of a bloom in photographs from residents. Lake closure advisories are posted via
Twitter and other online locations. Many residents of FPL do not have internet access at the
lake. An NSE advisory posted via Twitter in the summer of 2021 did not reach the majority
of lake residents.
23
Microcystin is not the only toxin produced by cyanobacteria. Anatoxins,
Cylindrospermopsins, Nodularins, Saxitoxins, Dermatoxtoxins, and other irritant toxins are
also produced by cyanobacteria (Health Canada 2012). The majority of commercial labs in
Canada do not test for these toxins. This means that the absence of Microcystin-LR in a water
sample does not mean that a bloom does not contain other toxins. Because of this, lake
residents should be made aware of all blooms and treat all blooms with the same level of
caution.
As algal blooms can be induced and intensified by increases in nutrients to ecosystems
(whether naturally from the 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.
4.3 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 (Figure 18). 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])
24
Table 3: The results of the 2022 TSI calculations for the 3 associated water quality parameters. Secchi depth was not taken in
June, so that parameter is missing from this calculation.
Parameter Calculated TSI Value
Secchi (Transparency) 50.17
Chl α 44.59
Phosphorous 29.99
TSI Result 41.58
Figure 18: Carlson TSI for FPL using the mean Secchi disk depth (transparency), mean chlorophyll-α concentration and mean
total phosphorus concentration within FPL in 2022. From Carlson, 1977.
For FPL, the trophic state was determined to be oligotrophic approaching mesotrophic from
2015-2019 and 2021, however, the TSI results for 2022 put FPL into the mesotrophic
category (Figure 19). 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
25
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 contribute excess nutrients, particularly phosphorus,
to a waterbody and increases the probability of the occurrence of cyanobacterial blooms
(Necombe et al. 2010).
Figure 19. Comparison of FPL TSI scores from 2015 to 2022 and trophic states, using the Carlson (1977) trophic equations for
total phosphorus (TP), chlorophyll-α (Chla), and Secchi disk (Secchi).
4.4 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 trapped within the lake substrate (i.e., orthophosphate)
or nutrients trapped in the water below the thermocline, and therefore are unable to be
mixed and dispersed throughout the lake (Sondergaard et al. 2003; Kennedy and Walker
1990).
26
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. The
elevated nutrient concentrations of these two inlet streams suggest a level of pollution
related 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 are an
additional internal loading source. 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 at-depth waters (below the thermocline) within FPL.
Surface Waters At-Depth Waters
2019 2020 2021 2022 2019 2020 2021 2022
Phosphorus Concentrations
(mg/L)
0.007 0.261 0.007 0.006 0.012 0.246 0.010 0.010
Nitrogen Concentrations
(mg/L)
0.007 0.304 0.267 0.257 0.014 0.288 0.572 0.389
The residential development occurring along the South Inlet may 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 if not properly contained.
The water samples from the South Inlet and Secondary Southern site, below this property,
showed little difference in phosphorous and nitrogen between the two sites (Table 5). This
suggests that there is little to no impact from the farm in 2022.
27
Table 5: Nutrient concentrations of total phosphorus (TP) and total nitrogen (TN) from the two South Inlet sites following
rainfall events from 2019 - 2022.
South Inlet South Culvert Site Difference
2019 2020 2021 2022 2019 2020 2021 2022 2019 2020 2021 2022
TP
(mg/L)
0.049 0.645 0.063 0.058 0.049 0.056 0.063 0.067 0.000 -0.589 0.000 -0.009
TN
(mg/L) 0.065 0.714 0.461 0.835 0.661 0.691 0.461 0.82 0.596 -0.023 0.000 0.015
5.0 Recommendations
Below are recommendations for the next steps in Fox Point Lake.
1) Review and discuss the continuation of FPL water quality monitoring for 2023.
Additional project activities that we suggest to be considered are:
• Use of a Sand Wand to remove fine sediment embedded in the South Inlet to improve
aquatic habitat quality. After multiple years of sedimentation runoff, the stream bed has
become heavily sedimented and holds excess nutrients that may continue to impact the lake
for many years.
• Assess South Inlet for other aquatic habitat qualities that may need to be remediated
(i.e., debris jams, unstable banks, or point-source pollutants such as agriculture practices
within the riparian zone). Excess sand and silt in streams can reduce habitat for aquatic
invertebrates, as well as widen the stream and reduce water flow (Adopt a Stream 2020).
Removing the fine materials from the South Inlet stream bed could improve fish spawning
and invertebrate habitats, as well as improve water flow and stream health over time.
28
6.0 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.
Canadian Council of Ministers of the Environment (CCME). 2004. Canadian water quality
guidelines for the protection of aquatic life: phosphorus: Canadian guidance framework for
the management of freshwater systems. In: Canadian environmental quality guidelines,
2004, 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 during
1984. N.S. Dept. Env. Lib. L192.1 85/00 C2. 38 p.
29
Jones, G.J. and Orr, P.T. 1994. Release and degradation of microcystin following algicide
treatment of a Microcystis aeruginosa bloom in a recreational lake, as determined by HPLC
and protein phosphatase inhibition assay. Water Res., 28: 871–876.
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.
Michalak, A.M., Anderson, E.J., Beletsky, D., Boland, S., et al. 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.
Nova Scotia Salmon Association (NSSA) Adopt-A-Stream Program. 2020. SandWand.
Accessed Feb 10, 2023 [http://adoptastream.ca/project-design/sandwand]
Nova Scotia Salmon Association (NSSA) NSLC Adopt-A-Stream Program. 2014. Walking the
River: A Citizen’s Guide to Interpreting Water Quality Data. 43 p.
Nova Scotia Salmon Association (NSSA) NSLC Adopt-a-Stream Program. 2015. Acid Rain.
[http://www.nssalmon.ca/issues/acid-rain].
Ontario Ministry of the Environment (MOE). 1979. Rationale for the establishment of
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