Transcript Sturbridge Lakes Monitoring Report 2002-2003

Sturbridge Great Ponds
2010 Annual Monitoring Report
Presented by:
David Mitchell
Sponsored by:
Sturbridge Conservation Commission and
Sturbridge Lakes Advisory Committee
Sturbridge Senior Center
June 17, 2010
Tonight’s Presentation
• Introduction to Sturbridge Conservation
Commission (SCC) Lake Monitoring Program
• Results from Summer 2009 Lake Sampling and
Data Comparisons between Lakes
• Planning for 2010 Lake Monitoring Program
• Discussion of U.S. EPA 2010 National Lake
Assessment Report
• Update on Sturbridge Lakes Advisory
Committee (SLAC) activities
SCC Lakes and Ponds Inventory,
Monitoring, and
Management Strategy
• Conduct Annual Lake and Pond Monitoring
• Develop Sturbridge Lake and Pond Water
Quality Database
• Watershed Delineation and Characterization
• Coordinate with Lake Associations to develop
long-term Lake Management and Watershed
Protection Plans (LM/WPPs) – QQLA (South
Pond) has just developed a long-term LM plan
Great Ponds* of Sturbridge
Currently Being Monitored
•
•
•
•
•
•
Big Alum Pond
Cedar Lake
East Brimfield Reservoir/Long Pond
Leadmine Pond
South (Quacumquasit) Pond
Walker Pond
* Defined by MGL Chapter 91.36 as ponds containing in their natural
state more than ten acres of land, and subject to any rights in such
ponds which have been granted by the Commonwealth.
Reasons for Lake Monitoring
• Provides baseline data
to compare with future
data to detect trends
• Forms basis for
conducting informed
lake management
• Allows evaluation of
efficiency of various
treatments
• Economic incentives
for protection of lake
real estate values
Lakes Monitoring Program
• Lakes sampled during mid-summer (July-Aug.)
• Central location (deep hole) and other location
– Shallow (0.5 ft) and deep (2-3 ft off bottom)
• Thermal and dissolved oxygen (DO) profiles
• Secchi Disk Transparency (SDT)
• Water Quality Samples taken:
– Nutrients - nitrogen and phosphorus fractions
– Other - alkalinity, hardness, TSS, iron, conductivity
– Biological – chlorophyll a, zooplankton
Sturbridge Great Ponds
Size (ac)
Depth (ft)
Watershed
to Lake
Area Ratio
Big Alum
Pond
195
45+
3:1
Natural with
dam
Cedar Lake
183
15
12:1
Natural with
dam
E. Brimfield
Reservoir
420
22
103:1
Natural with
dam
Lake
Origin
Natural
Leadmine
Pond
53
55
11:1
South Pond
225
60+
5:1
Natural
15:1
Natural with
dam
Walker
Pond
171
15
Thermal and Dissolved Oxygen
Profiles and SDT Measurement
How deep is your lake?
• Average lake depth is
important
– Influences light availability
for aquatic weeds
– Lakes with >15-20 ft will
usually seasonally stratify
Is there a single water layer
or a deeper colder layer where
the big trout are lurking?
• Forms two layers with
different temperature and
water quality in summer
– Algal blooms usually
confined to upper layer
– Bottom layer may provide
coldwater fish habitat
– Recycling of nutrients
... and even deeper?
South Pond Temperature (Co)
Depth Profile - August 14. 2009
0.00
0.0
5.00
10.00
15.00
20.00
25.00
5.0
Epilimnion
Depth (ft)
10.0
15.0
Thermocline
20.0
25.0
30.0
Hypolimnion
35.0
40.0
45.0
30.00
South Pond % DO Saturation Depth
Profile – August 14, 2009
0.0
20.0
40.0
60.0
80.0
100.0
0.0
5.0
Depth (ft)
10.0
Epilimnion
15.0
Thermocline
20.0
25.0
30.0
35.0
Hypolimnion
40.0
45.0
120.0
Sturbridge Deep Lakes 2009
Temperature and DO Depth Profiles
Deep Lake Temp. Profiles
Deep Lake % DO Profiles
% DO Saturation
0.00
0.0
5.00
10.00
15.00
20.00
25.00
30.00
0.0
5.0
40.0
60.0
80.0
100.0
5.0
10.0
10.0
15.0
15.0
20.0
20.0
Depth ( ft)
Depth ( ft)
20.0
0.0
25.0
30.0
35.0
25.0
30.0
35.0
40.0
40.0
45.0
45.0
LP-1 Temp
BA-1 Temp
SP-1 Temp
LP-1 %DO
BA-1 %DO
SP-1 %DO
120.0
Sturbridge Shallow Lakes 2009
Temperature and DO Depth Profiles
Shallow Lakes Temp.
Profiles
10
20
0
30
0
0
2
2
4
4
6
6
Depth (ft)
Depth (ft)
0
Shallow Lakes % DO
Profiles
8
10
12
60
80
100
10
12
14
16
16
CL-1 Temp
40
8
14
WP-1 Temp
20
CL-1 %DO
WP-1 %DO
120
Water Quality Sampling
Big Alum Pond
BA-2
BA-1
CL-2
CL-1
Cedar Lake
East Brimfield Reservoir /
Long Pond
EBR-2
• Largest Great Pond in
Sturbridge and last to
be monitored
• Only shoreline-based
monitoring in 2009
• Initial water quality
data indicates some
influence of Route 20
LP-1
LP-2
SP-1
SP-2
WP-1
WP-2
Comparisons in Water Quality between
Deep and Shallow Lakes: 2002-09 data
Shallow Lakes
Deep Lakes
– Max. depth = 16 ft
– Max. depth = 45-60+ ft
– SDT = 6.1 ft (n=26)
– SDT = 15.3 ft (n=48)
– Alkalinity = 10.3 mg/L (n=39)
– Alkalinity = 10.9 mg/L (n=58)
– Sp. Cond = 294 uS (n=50)
– Sp. Cond = 94.0 uS (n=70)
– Sodium = 42.1mg/L (n=41)
– Sodium = 7.6 mg/L (n=59)
– Chloride = 71.8 mg/L (n=40)
– Chloride = 15.3 mg/L (n=59)
– Chl a = 8.7 ug/L (n=10)
– Chl a = 5.75 ug/L (n=15)
Carlson’s Trophic State Indicators
Comparison of 2009 TSI scores for
Sturbridge Lakes
Lake
Big Alum
Pond
Chl a
(ug/L)
NA
TP
(ug/L)
8
SDT
(ft)
15.7
Cedar Lake
E. Brimfield
Reservoir
NA
21
3.3
NA
17
5.0
• Mean Carlson TSI Scores
• Big Alum Pond = 36
• Cedar Lake = 54
• EBR/Long Pond = 49
Leadmine
Pond
NA
18
15.5
South
Pond
NA
8
12
• South Pond = 38
Walker
Pond
NA
21
8.5
• Walker Pond = 47
• Leadmine Pond = 42
Trophic States of Sturbridge Lakes
• TSI Score & Trophic • Sturbridge Lakes
• Big Alum: Oligotrophic
Classifications
• Oligotrophic= < 38
(poorly fertilized)
• Mesotrophic = 38-47
(moderately fertilized)
• Eutrophic = 48-66
(well fertilized)
• Hypereutrophic = > 66
(extremely fertilized)
• Cedar Lake: Eutrophic
• EBR/Long Pond: Eutrophic
• Leadmine: Mesotrophic
• South: Oligo-Mesotrophic
• Walker: Mesotrophic
Comments on 2009 Monitoring
Program Results (1)
• Lake water quality indicates generally good
conditions, but some mixed signals
– Water clarity values well within seasonal ranges
previously recorded
– Higher TP and DP observed this year
• Big Alum Pond good score, but productivity is
showing up in oxygen deficits at bottom
• Cedar Lake is challenged by low water clarity
and high nutrient levels
• East Brimfield Reservoir – appears to eutrophic,
which is consistent with its weedy conditions
Comments on 2009 Monitoring
Program Results (2)
• Leadmine Pond appears to be trending to
slightly lower SDT, still the most weed-free
• South Pond has variable record, probably due to
North Pond influences; last year was good.
• Walker Pond had good year, high TP near north
end noted
• Overall, results are well within the variability
seen in the last 7 years.
Common and non-native invasive aquatic
macrophytes in Sturbridge Lakes
Common species:
• Chara / Nitella
• Elodea canadensis
• Myriophyllum
heterophyllum
• Najas flexilis
• Potomogeton (10 species)
• Utricularia
• Vallisneria americana
Non-indigenous
invasive species:
• Cabomba caroliniana
(South Pond)
• Myriophyllum spicatum
(South Pond)
• Potomogeton crispus (Big
Alum Pond, Cedar Lake)
Thanks to All the 2009 Lake
Monitoring Volunteers
• SCC – Dave Mitchell, Erin Jacques, Matt
Mitchell, Peter Logan
• Big Alum Pond – Bruce Gran
• Cedar Lake – Pat Wondolewski
• Leadmine Lake – Laurel and Steve Carpenter
• South Pond – Marita and Jeff Tasse
• Walker Pond – Doug Smith
Sturbridge Lakes Monitoring 2010
• SCC Lake Monitoring
– We will conduct another round of physiochemical
measurements and WQ sampling.
– Sampling tentatively scheduled for Friday-Saturday
in August
– Exact schedule of lake sampling to be finalized in July
• Many thanks to those who have already given
generously of their time to make these events
happen and the monitoring successful.
• Volunteers and boats are always appreciated !
National Lakes Assessment
• The National Lakes Assessment (NLA) is the first-ever
baseline study of the condition of the nation’s lakes and
results were recently reported by USEPA (2010).
• The NLA provided unbiased estimates of the condition
of natural and man-made freshwater lakes, ponds, and
reservoirs >10 acres and at least one meter deep.
– Using a statistical survey design, lakes were selected at random
to represent the condition of the larger population of lakes
across the lower 48 states.
– A total of 1,028 lakes were sampled for the NLA during summer
2007, representing the condition of about 50,000 lakes
nationwide.
• The NLA finds that 56% of the nation’s lakes support
healthy biological communities when compared to least
disturbed sites; with 21% “fair” and 22% judged “poor”
U.S. EPA, 2010
This rating is based on an index of phytoplankton and zooplankton
taxa loss – the percentage of taxa observed compared to those that
are expected, based on conditions at least-disturbed lakes
What are the stress factors for lakes?
• Water Quality and Chemistry
–
–
–
–
Total Phosphorus
Total Nitrogen
Dissolved Oxygen
Turbidity
• Aquatic Habitat
–
–
–
–
Lake Shoreline Disturbance
Lake Shoreline Habitat
Shallow Water Habitat
Physical Habitat Complexity
Extent and Risk of Stressors
U.S.EPA, 2010
It is not just nutrients !
• Large amount of risk associated with poor
habitat conditions – lakeshore and shallow water
– Lakeshore habitat is rated poor in 36% of lakes.
– Poor biological health is three times more likely in
lakes with poor lakeshore habitat relative to lakes
with good habitat.
• The nutrients nitrogen and phosphorus are at
high levels in about twenty percent of lakes.
– Poor biological health is 2.5 times more likely in lakes
with high nutrient levels.
National Trends – Somewhat encouraging
• A comparison of NLA data to a subset of wastewaterimpacted lakes sampled 35 years ago suggests that the
nation’s investments in wastewater treatment and other
pollution control activities are working despite increased
population pressures across the United States.
• The report finds that nearly 75% of the 800 lakes
sampled in the 1970s showed either improvements or no
change in phosphorus levels.
• Trophic status also improved or remained the same in
about 75% of those lakes.
Take-home messages for
Sturbridge Shoreline Residents
• Healthy lakes often have “messy”
shorelines with lots of natural vegetation
• Lake shallows “cleanups” during
drawdown do not promote a better lake
• Try to limit your shoreline “footprint” as
much as possible
• For more information or to get a copy of
the National Lakes Assessment, visit
http://www.epa.gov/lakessurvey.
Sturbridge Lakes Advisory Committee
(SLAC) Background
• Established by Sturbridge Board of Selectmen in Dec. 2007
to get lake associations from five Great Ponds together to
identify common concerns and issues and provide
recommendations to Selectmen;
• SLAC met between March and July 2008, summary Final
Report and recommendations presented to Town and
discussed with Selectmen in January 2009;
• SLAC officially recognized by Town through passage of
warrant article at June 8th 2009 Town Meeting; and
• SLAC representatives appointed in spring 2009 and have
been meeting to identify and recommend action items.
List of SLAC Lake Representatives
• Town of Sturbridge Selectmen – Teddy Goodwin;
• Sturbridge Conservation Commission - Donna Grehl;
• Big Alum Lake Association – Joel Casaubon, Tammy
Chase (Secretary), Bruce Gran;
• Cedar Lake Association – Greg Abrams, Fran O’Connell;
• United States Army Corps of Engineers (USACE) - Tom
Chamberland (for East Brimfield Reservoir / Long Pond);
• Leadmine Pond Association – Laurel/Steve Carpenter.
Bill Kenyon (former), Laurie Palmer;
• Quaboag-Quacumquasit Lake Association (QQLA) –
Chris Reidy, Marita Tasse, David Mitchell; and
• Walker Pond Association – Greg Hale, John O’Brien Jr.
Sturbridge Lakes Advisory
Committee (SLAC) Mission Statement
• The mission of the Sturbridge Lake Advisory
Committee is to establish wise stewardship and
an effective management mechanism for the
sustainable use of the Town’s water resources
and protection of their watersheds. Lake
management should be developed through
consensus from a collaborative, community
wide pool of stakeholders that shall include lake
users, lake associations, civic groups, and
municipal government.
Goals of the SLAC
• SLAC encourages wise use and enjoyment of
our Great Ponds coupled with environmentallysound stewardship of these common resources;
• SLAC looks to create and enhance public
awareness within Sturbridge, of the lakes, their
range of resources and their overall value to the
community; and
• SLAC will work to develop recommendations
for the Board of Selectmen to better protect and
preserve these important natural resources.
Common Concerns and Issues
• SLAC has identified several concerns or issues
generally recognized to be relevant for some or
all of the Sturbridge Lakes surveyed.
• SLAC Sub Committees have been formed to
address these concerns or issues:
–
–
–
–
–
–
–
Boating Regulations,
Aquatic Plant Management,
Water Quality,
Community Outreach,
Legislative,
Communications, and
Funding.
Continuing Activities for SLAC (1)
• Gather useful information and best
management practices from diverse
sources: State, internet, literature, other
lake associations, etc.
– Recent presentation on organization and
funding by Dick Cazeault, WLA president
• Sub-Committee members will continue to
meet to provide solutions for issues that
can be shared and implemented by all
• Coordinate activities with Town agencies
and keep Selectmen informed of progress
Continuing Activities for SLAC (2)
• SLAC meetings held on last Wednesday of
the month at the Sturbridge Senior Center
– Look to recruit additional volunteers to work
on the high priority issues;
– Don’t need to be in a lake association to join!
• For additional information contact:
– John O’Brien (SLAC president) at:
[email protected]
– Selectman Teddy Goodwin at:
[email protected]
Photo credits
• Big Alum Pond aerial – Lycott website
• Cedar Lake – Pat Wondolewski
• East Brimfield Reservoir – USACE website
• Leadmine Lake – Bill Kenyon
• South Pond – Donna Grehl
• Walker Pond – John Hoffman
QUESTIONS ?
2009 Lake Sampling Stations and Parameters
Lake
Big Alum
Lake
Cedar Lake
E. Brimfield
Reservoir /
Long Pond
Leadmine
Pond
South Pond
Walker Pond
Stations
Parameters
BA-1S, BA-2
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, SDT
BA-1D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA,
CL-1S, CL-2S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, SDT
CL-1D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA,
EBR-1S,
EBR-2S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, SDT
LP-1S, LP-2S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, SDT
LP-1D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA,
SP-1S, SP-2S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, SDT
SP-1D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA,
WP-1S,
WP-2S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, SDT
WP-2D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA,
Big Alum Pond BA-1 (8/14/2009)
Nutrients and Secchi Disk Depth
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
TOT. NITROGEN
SECCHI DISK (ft)
BA-1S
BA-1D
BA-2S
Shallow
Deep (35 ft)
Shallow
0.008
0.005
0.070
0.380
0.385
0.061
0.005
0.420
0.870
0.875
0.009
0.005
0.025
0.300
0.305
15.7
-
15
Cedar Lake (8/15/09)
Nutrients and Secchi Disk Depth
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
TOTAL N
SECCHI DISK (ft)
Shallow Deep (12 ft) Shallow
0.021
0.082
0.029
0.005
0.010
0.020
0.025
0.070
0.025
0.370
0.580
0.370
0.375
0.590
0.390
3.3
2.9
East Brimfield Reservoir (8/14/09)
Nutrients and Secchi Disk Depth
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
TOTAL N
EBR-1S
Shallow
0.017
0.010
0.025
0.350
0.365
EBR-2S
Shallow
0.013
0.005
0.050
0.350
0.395
Leadmine Pond LP-1 (8/15/09)
Nutrients and Secchi Disk Depth
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
TOT. NITROGEN
SECCHI DISK (ft)
Shallow Deep (35 ft) Shallow
0.018
0.039
0.020
0.005
0.080
0.005
0.025
0.100
0.090
0.230
0.330
0.520
0.235
0.410
0.525
15.5
-
14.5
South Pond SP-1 (8/14/09)
Nutrients and Secchi Disk Depth
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
TOT. NITROGEN
SECCHI DISK (ft)
SP-1S
SP-1D
SP-2S
Shallow Deep (39 ft) Shallow
0.008
0.009
0.004
0.005
0.020
0.005
0.025
0.070
0.025
0.330
0.350
0.330
0.335
0.370
0.335
12
-
12
Walker Pond WP-2 (8/15/09)
Nutrients and Secchi Disk Depth
TOT. NITROGEN
WP-2S
Shallow
0.020
0.005
0.090
0.500
0.505
WP-2D
Deep(12 ft)
0.040
0.005
0.090
0.800
0.805
WP-1S
Shallow
0.095
0.090
0.050
0.450
0.540
SECCHI DISK (ft)
8.5
-
7
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
Basic Principles For Lake Management
• Fresh water is a finite, fragile and valuable resource with profound
biological complexity and intrinsic beauty. Water has an economic
value in all its competing uses, and should be recognized as an
essential good. Each lake has its own unique natural and manmade
characteristics.
• Excessive utilization and degradation of lake resources will cause
significant lake problems and reduce its value to the community. The
wise and prudent use of water resources should contribute directly to
sustainable socioeconomic development while preserving their natural
aquatic and terrestrial ecosystems.
• The management of lakes for their sustainable use requires the
resolution of conflicts among competing users of the lake resources,
taking into account the needs of present and future generations and
nature. Decision making for lake management should be based on
sound science and the best available information. Good governance,
based on fairness, transparency and empowerment of all stakeholders
is essential.