Transcript Sturbridge Lakes Monitoring Report 2002-2003

Sturbridge Lakes
2008 Annual Data Report
Presented by:
David Mitchell
Sturbridge Conservation Commission
Sturbridge Town Hall
June 18, 2008
Tonight’s Presentation
• Introduction
• Sturbridge Conservation Commission (SCC)
Lake Policy and Lake Monitoring Program
• Results from Summer 2007 Lake Sampling and
Data Comparisons between Lakes
• Planning for 2008 Lake Monitoring Program
SCC Lakes Policy
The Town of Sturbridge is fortunate to have abundant water
resources, including many lakes and ponds with significant
scenic, ecological and recreational values. For the most part,
these waterbodies exhibit good water quality and are largely
unimpaired by nuisance algal blooms and excessive
macrophyte growth. Future water quality in these lakes and
ponds will be challenged by the continuing growth and
development in the watersheds. It is therefore necessary to
monitor the lakes regularly to detect undesirable trends at an
early stage and to promote and develop appropriate and
effective lake and watershed management
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 define
and develop long-term Lake Management and
Watershed Protection Plans (LM/WPPs)
Great Ponds* of Sturbridge
Currently Being Monitored
•
•
•
•
•
Big Alum Pond
Cedar Lake
Leadmine Pond
South (Quacumquasit) Pond
Walker Pond
* Defined (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.
Sturbridge Great Ponds
Lake
Size (ac)
Depth (ft)
WA:SA*
Origin
Big Alum
Pond
Cedar
Lake
195
45+
3:1
Natural with
dam
183
15
12:1
Natural with
dam
Leadmine
Pond
South
Pond
53
55
11:1
Natural
225
60+
5:1
Natural
171
15
15:1
Natural with
dam
Walker
Pond
* WA = watershed surface area; SA = lake surface area
Other Lake and Ponds in Sturbridge
Currently Not Monitored
•
•
•
•
•
East Brimfield/Long Pond (USACE)
Westville Lake (USACE)
Breakneck Pond
McKinstry Pond
Pistol Pond
Reasons for Lake Monitoring
• Provides baseline data
to compare with any
future change
• Basis for conducting
informed lake
management
• Evaluate 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
2007 Lake Sampling Stations and Parameters
Lake
Stations
Big Alum Lake
BA-1S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, BOD, FC, TC, Chl A, ZOOP, SDT
BA-1D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA, BOD
BA-2
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, FE, CL, FC, TC, SDT
CL-1
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, BOD, FC, TC, Chl A, ZOOP, SDT
CL-1D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA, BOD
CL-2
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, FE, CL, FC, TC, SDT
LP-1S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, BOD, FC, TC, Chl A, ZOOP, SDT
LP-1D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA, BOD
LP-2
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, FE, CL, FC, TC, SDT
SP-1S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, BOD, FC, TC, Chl A, ZOOP, SDT
SP-1D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA, BOD
SP-2
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, FE, CL, FC, TC, SDT
WP-2S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, CL, FE, NA, BOD, FC, TC, Chl A, ZOOP, SDT
WP-2D
TP, DP, NH3, NO3, NO2, TKN, ALK, TSS, CL, FE, NA, BOD
WP-1S
TP, DP, NH3, NO3, NO2, TKN, ALK, HARD, TSS, FE, CL, FC, TC, SDT
Cedar Lake
Leadmine Pond
South Pond
Walker Pond
Parameters
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?
Temperature DO Profile SP-1
8/11/07
Degrees ( oC)
0
10
20
0
5
10
Depth ft
15
20
Epilimnion
Thermocline
25
30
35
Hypolimnion
40
45
50
Temperature Profile SP1
30
Dissolved Oxygen Profile SP-1
8/11/07
% saturated DO
0
50
100
0
5
10
Depth ft
15
20
25
30
35
40
45
50
% Sat. DO
150
Sturbridge Deep Lakes 2007
Temperature and DO Depth Profiles
Deep Lakes - Temperature Profiles
Deep Lakes - % DO Profiles
Tem perature ( oC)
10.0
20.0
30.0
0.0
0
0
5
5
10
10
15
15
Depth ft
Depth ft
0.0
% DO Saturation
20
25
35
35
40
40
45
45
BAP-1 Temp
60.0
80.0 100.0 120.0
25
30
SP-1 Temp
40.0
20
30
LP-1 Temp
20.0
LP-1 %DO
BA-1 %DO
SP-1 %DO
Sturbridge Shallow Lakes 2007
Temperature and DO Depth Profiles)
Shallow Lakes - Temperature Profiles
Shallow Lakes - % DO Profiles
Tem perature ( oC)
10
20
30
0
0
0
3
3
6
6
Depth ft
Depth ft
0
% DO Saturation
9
12
15
15
WP-2 Temp
40
60
80
100
9
12
CL-1 Temp
20
CL-1 %DO
WP-2 %DO
120
Water Quality Sampling
Big Alum Pond
BA-2
BA-1
Big Alum Pond BA-1 (8/11/2007)
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
0.026
0.005
0.02
0.1
0.13
0.5
0.005
0.04
0.3
0.35
0.029
0.005
0.005
0.2
0.21
19.7
-
19.5
CL-2
CL-1
Cedar Lake
Cedar Lake (8/11/07)
Nutrients and Secchi Disk Depth
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
TOTAL N
SECCHI DISK (ft)
Shallow Deep (15 ft) Shallow
0.047
0.065
0.047
0.01
0.02
0.01
0.06
0.24
0.06
1
1.1
0.6
1.07
1.36
0.87
4.3
NA
To bottom
LP-1
LP-2
Leadmine Pond LP-1 (8/10/07)
Nutrients and Secchi Disk Depth
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
TOT. NITROGEN
SECCHI DISK (ft)
LP-1S
LP-1D
LP-2S
Shallow Deep (45 ft) Shallow
0.031
0.058
0.063
0.005
0.01
0.005
0.02
0.4
0.005
1.3
1.1
0.4
1.33
1.51
0.41
15
-
17.3
SP-1
SP-2
South Pond SP-1 (8/11/07)
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 (45 ft) Shallow
0.063
0.044
0.0029
0.005
0.01
0.02
0.02
0.03
0.02
0.5
0.3
0.1
0.53
0.34
0.14
12.4
-
11
WP-1
WP-2
Walker Pond WP-2 (8/11/07)
Nutrients and Secchi Disk Depth
TOT. NITROGEN
WP-2S
Shallow
0.023
0.005
0.39
0.8
1.20
WP-2D
Deep(12 ft)
0.047
0.005
0.36
1.3
1.67
WP-1S
Shallow
0.059
0.005
0.36
1.4
1.77
SECCHI DISK (ft)
6.3
-
6
Parameter (mg/L)
TOT. PHOSPHORUS
NITRATE-N
AMMONIA-N
T. KJELDAHL-N
Comparisons in Water Quality between
Deep and Shallow Lakes – 2002-07 data
Shallow Lakes
Deep Lakes
– Max. depth = 16 ft
– Max. depth = 45-60+ ft
– SDT = 6.2 ft (n=18)
– SDT = 15.8 ft (n=36)
– Alkalinity = 11.7 mg/L
– (n=31)
– Alkalinity = 11.9 mg/L
(n=38)
– Sp. Cond = 312 uS (n=36)
– Sp. Cond = 90.9 uS (n=54)
– Sodium = 45.5 mg/L (n=27)
– Sodium = 7.4 mg/L (n=39)
– Chloride = 79.4 mg/L (n=26)
– Chloride = 15.3 mg/L (n=39)
– Chl a = 8.1 ug/L (n=8)
– Chl a = 4.5 ug/L (n=12)
Biological Sampling
Zooplankton Sampling 2003-2007
Sturbridge Lakes Crustacea Mean Length (mm)
for 2003-2007
1.20
1.00
0.80
2003
2005
0.60
2006
0.40
2007
0.20
0.00
Big Alum
Pond
Cedar
Lake
Leadmine
Pond
South
Pond
Walker
Pond
Carlson’s Trophic State Indicators
Comparison of 2007 TSI scores for
Sturbridge Lakes
Lake
Big Alum
Pond
Chl a
(ug/L)
5.94
TP
(ug/)
26
SDT
(ft)
19.7
• Mean Carlson TSI Scores
• Big Alum Pond = 40
Cedar
Lake
17.05
47
4.3
Leadmine
Pond
4.92
31
16.2
South
Pond
4.26
29
11.7
• South Pond = 42
23
6.15
• Walker Pond = 43
Walker
Pond
• Cedar Lake = 52
• Leadmine Pond = 44
Trophic States of Sturbridge Lakes
• TSI Score & Trophic
Classifications
• Oligotrophic= < 38
(poorly fertilized)
• Mesotrophic = 38-47
(moderately fertilized)
• Eutrophic = 48-66
(well fertilized)
• Hypereutrophic = > 66
(extremely fertilized)
• Sturbridge Lakes
• Big Alum – Mesotrophic
• Cedar Lake – Eutrophic
• Leadmine – Mesotrophic
• South – Mesotrophic
• Walker - Mesotrophic
Trophic States of Sturbridge Lakes
(composite of 2004-2006 data)
• TSI Score & Trophic
Classifications
• Oligotrophic= < 38
(poorly fertilized)
• Mesotrophic = 38-47
(moderately fertilized)
• Eutrophic = 48-66
(well fertilized)
• Hypereutrophic = > 66
(extremely fertilized)
• Sturbridge Lakes
• Big Alum - Oligo-mesotrophic
• Cedar Lake – Eutrophic
• Leadmine – Mesotrophic
• South – Mesotrophic
• Walker - Mesotrophic
Lake Stewardship for Watershed
• Your watershed consists of the all the surface
area and GW that supplies water to your lake
• Look to manage land use in the watershed to
reduce or mitigate future nutrient loading
– Implement best practices for shoreline owners
– Acquire key parcels in watershed
– Consider lake protection districting
• Support good lake management at the ballot box
Lake Stewardship for Lakeshore
• Prevention of nutrients (phosphorus and
nitrogen) from entering Great Ponds
– Use low or no phosphorus fertilizer on lawns
– Eliminate/mitigate direct stormwater
discharge
• Establishment of a natural vegetation
buffer on the 20 feet nearest the lake
– Don’t have lawn to waters edge
– Provide overhanging vegetation (fish habitat)
– Prevent erosion and sediment entering lake
Lake Stewardship for In-Lake
• Boat Launch and Operation
– Maintain adequate depth and angle for boat launch as
it flattens out over time and creates delta
– Keeps boat speed low near shallow depth as prop
wash will re-suspend sediment material
• Shoreline cleanup
– Don’t dispose of leaves and organic materials in lake,
it will lead to reduction in dissolved oxygen
• Don’t ever dispose of unused bait fish or discard
aquarium plants into lake
– this is how non-indigenous species get into a lake !
Sturbridge Lakes Monitoring 2008
• SCC Lake Monitoring
– We will conduct another round of physiochemical
measurements and WQ sampling.
– Sampling tentatively scheduled for Friday August 8th
and Saturday 9th, 2008
– Exact scheduling of sampling will be finalized in midJuly
• Many thanks to those who have already given
generously of their time to make these events
happen.
• Volunteers and boats are always appreciated !
Thanks to All the 2007 Lake
Monitoring Volunteers
• SCC – Donna Grehl, Kelly Kippenburger,
Matt Mitchell, Dave Mitchell
• Big Alum Pond – Scott Sanderson and kids
• Cedar Lake – Pat Wondolowski
• Leadmine Lake – Jim Dunn and Gary Craig
• South Pond – Marita and Jeff Tasse
• Walker Pond – Doug Smith
Photo credits
• Big Alum Pond aerial – Lycott website
• Leadmine Lake – Bill Kenyon
• South Pond – Donna Grehl
• Walker Pond – John Hoffman
QUESTIONS ?