Revised March 2012
EcoLogic, LLC
Aquatic,
Terrestrial and Wetland Consultants
Cazenovia, NY 13035
Cornell
Biological Field Station
Onondaga County
Department of Water Environment Protection
Environmental
Engineer
This report
presents the findings of
The 2010 report
was prepared and distributed as an electronic document. Key results and supporting tables and
graphics are included in the main document, with links to supporting tables,
technical reports and graphics in an electronic library. The report and supporting files are available
on CD upon request and on the
Once in the library of supporting documents, the reader can navigate back to the main report using browser navigation tools such as the back arrow. There are more than 200 supporting tables and graphics in the library of supporting materials. While each hyperlink has been checked, it is possible that some features will not be enabled on every computer’s operating system. Feedback on the functionality of the electronic features of the document is welcome. Please contact JeannePowers@ongov.net with comments.
Table
of Contents- AMP 2010
Section 1. Introduction to the AMP
1.2 Classification
and Best Use
1.4 Amended
Consent Judgment Milestones
1.5 Projects
to address legacy industrial pollution.
1.6 Use
of metrics to measure and report progress
Section 2. Onondaga Lake and Watershed
2.1 Watershed
size and hydrology
Section 3. Onondaga County Actions
Section 4. Tributary Results: 2010 Results and
Trends
4.2.1 Compliance with ambient water quality standards
4.2.4 Tributary macroinvertebrates
Section 5. Onondaga Lake Water Quality: 2010
Results and Trends
5.3.3 Secchi Disk Transparency
5.7 Nearshore
condition and trends
5.7.1 Nearshore water clarity trends
5.7.2 Fecal coliform bacteria trends
5.8 Trends
in Metro improvements and lake response
Section 6. Biology and Food Web: 2010 Results
and Trends
6.1 Primary
producers- Algae and Macrophytes
6.2 Zooplankton
and dreissenid mussels
6.3 Littoral
macroinvertebrates
6.4.4 Fish Size – Largemouth Bass
6.4.5 Fish Size – Smallmouth Bass
6.4.7 Fish Size – Yellow Perch and Brown Bullhead
6.4.8 Angler Catch Rates of Bass
6.6 Additional
information regarding the fish community
6.7 Integrated
assessment of the food web
Section 7. Seneca River: 2010 Conditions and
Trends
Section 8. Progress with related initiatives
Section 9. Emerging issues and recommendations
List of Acronyms and Glossary of Terms
Library of Supporting Materials
LIST OF TABLES
Table EX- 1. Summary of Metrics, Onondaga Lake 2010
Table 1‑1. Overview of AMP data analysis and
interpretation plan.
Table 1‑2. Metro compliance schedule.
Table 1‑3. CSO compliance schedule.
Table 3‑2. CSO remedial projects (gray
infrastructure) planned.
Table 4‑1. Summary of tributary compliance
with ambient water quality standards, 2010.
Table 4‑3. Load
of selected nutrients, salts and bacteria to Onondaga Lake, 2010.
Table 4‑4. Percent annual loading
contribution by gauged inflow, 2010.
Table 4‑8. Ten-year trends in tributary
concentrations (2001-2010) – summary.
Table 4‑9. Ten-year trends in tributary
loading (2001-2010) – summary.
Table 4‑10. Incidence
of chironomid deformities, Onondaga Lake tributaries, 2010.
Table
5‑1. Onondaga
Lake compliance with ambient water quality standards and guidance
values, 2010.
Table 5‑3. Summary
of trends in lake concentrations, 2001-2010.
Table
6‑1. Species list of aquatic macrophytes observed in Onondaga Lake
Table 6‑3. Fish species identified in
Onondaga Lake, 2000-2010.
Table
7‑1. Summary of non-compliance with
selected AWQS, Three Rivers, 2010.
LIST OF FIGURES
Figure EX- 1. Daily average discharge of Ammonia-N
(NH3-N)
to Onondaga Lake from Metro, 1990-2010.
Figure EX- 2. Daily average phosphorus (TP) loading
from Metro, 1990-2010.
Figure EX- 4. Ammonia input to Onondaga Lake,
1990-2004 and 2010.
Figure EX- 6. Total phosphorus input to Onondaga
Lake, 1990-2004 and 2010.
Figure EX- 7. Summer algal bloom frequency, Onondaga
Lake, 1990 – 2010.
Figure EX- 10. Aquatic plant coverage, 2000 and
2010.
Figure EX- 11. Number of macrophyte species
identified in Onondaga Lake, 2000, 2005 and 2010.
Figure 1‑1. Tributary
and lake regulatory classifications and subwatershed boundaries.
Figure 1‑2. Map
of monitoring locations, Onondaga Lake and tributaries.
Figure 2‑1. Annual
average inflows to Onondaga Lake, 2001-2010.
Figure 2‑2. Land
cover classification map.
Figure 4‑1. Fecal
coliform bacteria abundance, Onondaga Lake tributaries, 2010.
Figure 4‑2. Watershed
(non-Metro) TP annual load and annual rainfall, 1990-2010.
Figure 4‑3. Biological
assessment designations, Onondaga Lake tributaries, 2000- 2010.
Figure 4‑4. Metro
NH3-N, 2010 effluent concentration compared to permit limits.
Figure 4‑5. Metro
TP, 2010 effluent concentration compared to permit limit.
Figure
5‑1. Chlorophyll-a concentration, January to December, 1998-2010.
Figure
5‑3. Secchi Disk transparency, Onondaga Lake South Deep, 2010.
Figure
5‑4. TSI conditions based on summer (June 1 – September 30) data, 1998-2010.
Figure 5‑8. Relationship
of Metro TP loading and lake summer TP (panel A-linear regression)
Figure 5‑9. Onondaga
Lake upper waters total nitrogen to total phosphorus (N:P) ratio, 1998‐2010.
Figure 5‑10. LWL
concentrations of SRP, NO3-N and DO, 2006-2010.
Figure
6‑1. Reduction in the Onondaga Lake phytoplankton standing crop, 1998-2010.
Figure
6‑2. Proportional biomass of phytoplankton divisions, 2010.
Figure
6‑3. Phytoplankton community structure and biomass, 2010.
Figure
6‑4. Macrophyte distribution, 2000 – 2010.
Figure
6‑5. Average biomass of zooplankton, proportion of major groups.
Figure 6‑6. Biomass
of various Daphnia species in Onondaga Lake.
Figure
6‑7. Average size of all crustacean zooplankton in Onondaga Lake, 1996 – 2010.
Figure
6‑8. Average crustacean zooplankton length (mm), 2009 and 2010.
Figure
6‑9. Dreissenid mussel average density and biomass with standard deviation,
2002-2010.
Figure
6‑10. Relative abundance of dreissenid mussels, 2002-2010.
Figure
6‑11. Spatial depiction of littoral macroinvertebrate community data.
Figure 6‑12. Nesting survey
map and comparison of north vs. south-2010.
Figure
6‑13. 2010 Young-of-year Catch per Unit Effort (CPU) distribution by stratum
and species.
Figure
6‑15. Fish space metric, 2010, for coldwater and coolwater species.
Figure
7‑1. Three Rivers system study area.
Figure 7‑2. 2010
Seneca River hydrograph with sampling dates.
Introduction
This Annual Report of Onondaga County’s Ambient Monitoring Program (AMP) describes the State of Onondaga Lake in 2010. Conducted
annually since 1970, the County’s monitoring program provides water resource
managers, public officials, state and federal regulators, and the entire
community a window into the significant changes evident in
Changes in the lake ecosystem are the result of
multiple factors. Some of these factors reflect human intervention, notably,
the significant investment in improved wastewater treatment technology and the
ongoing efforts to remediate legacy industrial wastes. Other changes in the
Taken
together, the 2010 AMP results illustrate an ecosystem in flux. This Executive
Summary highlights selected measures of the lake’s current water quality and
biological conditions. Following this brief summary is the 2010 Annual AMP
Report, where the major findings are discussed in detail, along with supporting
documentation. These brief highlights are expanded to address additional
topics.
Report Format
The 2010 AMP annual report is a concise summary of major
findings with hyperlinks to a library of related
materials, including tables and graphs of historic data, and reports of
biological sampling. This paperless format was developed to advance two
objectives: first, to reach a broader audience, and second, to continue to find
ways to reduce our environmental footprint, through a commitment to green
initiatives. This format was envisioned as a means to enable
Finding: Improvements to the Wastewater Collection
and Treatment System have Reduced Nutrient Loading to
Prior to
2005, excessive discharges of municipal and industrial wastewaters and runoff
from urban and rural areas adversely affected the quality of
In light of the lake’s water quality impairments,
Figure EX- 1. Daily
average discharge of Ammonia-N (NH3-N) to
A physical-chemical High-Rate
Flocculated Settling (HRFS) technology, known as Actiflo®, came on line in February 2005 to enhance phosphorus
removal. This system has resulted in an 86% decline in phosphorus discharged
from Metro to
Figure EX- 2. Daily average phosphorus (TP) loading from Metro, 1990-2010.
Finding: Reduced
Ammonia and Phosphorus Loading from Metro have Improved Water Quality
Conditions
The 2010 monitoring results
document the continued significant improvements in
Figure EX- 3. Annual average ammonia-N concentrations,
Figure EX- 4. Ammonia input to Onondaga Lake, 1990-2004 and 2010.
Total phosphorus (TP)
concentrations in the lake’s upper waters have shown a steep decline over the last two
decades (Figure
EX-5). The summer 2010 upper waters TP averaged 25 µg/l, which is comparable to conditions in
nearby Oneida Lake and several of the smaller
During 2010, less than 20% of the
TP input to
Figure EX- 5. Average total phosphorus concentration, June 1 – Sept
30,
Figure EX- 6. Total phosphorus input to Onondaga Lake, 1990-2004 and 2010.
With the reduction in nutrient
levels, algal blooms have become less frequent.
Since 2005, the lake has exhibited no major algal blooms, which are
defined as chlorophyll-a measurements above 30 µg/L, a unit of
measurement equivalent to a part per billion (abbreviated as ppb). Moreover,
between 2008 and 2010 there have been no minor algal blooms, which are defined
as chlorophyll-a measurements above 15 µg/L, (Figure EX-7). This reduction
in algal abundance has improved dissolved oxygen conditions in the lake’s deep
waters. Algal cells settle through the water column and decompose in the deep
waters; this process depletes dissolved oxygen (DO) and ultimately affects
aquatic habitat. With the reduction in
algal abundance, deep-water DO resources are improving; the volume of the lake
affected by low DO and the duration of low DO (reported as volume-days
of anoxia) are in decline, indicating improved habitat
conditions (Figure EX-8).
Low DO in upper waters in October
– during fall turnover - was one of the lake’s most significant water quality
impairments with respect to protection of aquatic life. Since the advanced
wastewater treatment at Metro became operational in 2005, the fall DO
concentrations have remained consistently high, as measured by frequent in-situ
profile sampling during the fall mixing period (Figure
EX-9).
Figure EX- 7. Summer algal bloom frequency,
Figure EX- 8. Volume-days of anoxia (dissolved oxygen less than 0.5 mg/l) and hypoxia
(dissolved oxygen less than 2 mg/l),
Figure EX- 9. Minimum DO concentration in upper waters (0-3 m)
during fall turnover (October) in
Finding: Reduced Nutrient and Algae Levels, and Improved Oxygen
Resources are reflected in a Changed Biological Community
The reduction in phosphorus and
algae has resulted in clearer water throughout the lake. Light penetrates deeper into the lake, and
supports the growth of macrophytes (rooted aquatic plants and bottom-dwelling
algae) in nearshore shallow waters (the littoral zone). Macrophytes are an important component of the
lake’s ecology; they produce food for other organisms, provide habitat for
aquatic invertebrates, fish, and wildlife, and help stabilize sediments. The
percent of the littoral zone with macrophytes has increased five-fold since
2000 (Figure EX-10).
Not only are there more plants, a
2010 macrophyte survey revealed that the lake’s macrophyte community has become
far more diverse (Figure EX-11). Five of the 23
species found during the 2010 survey were not present in the 2000 or 2005
surveys. The increasing macrophytes provide spawning and nursery habitat,
shelter and food for the fish community.
Angler catch rates of gamefish such as largemouth bass have generally
increased since 2000, while the catch of smallmouth bass is declining (Figure EX.12).
Figure EX- 10. Aquatic plant coverage, 2000 and 2010.
Figure EX- 11. Number of macrophyte species identified in
Figure EX- 12. Bass
(smallmouth and largemouth adults) captured by electrofishing in Onondaga
Several important metrics of the fish community consider the
diversity and richness of the adult fish community, both littoral (near-shore)
and pelagic (open water). Richness is a count of the number of species within a
community, while diversity considers both the number of species present and
their relative abundance. In
Diversity of the fish community fluctuates in response to
the periodic peaks and crashes of two species of clupeid, the alewife (Alosa pseudoharengus) and gizzard shad (Dorosoma cepedianum). Abundance of these
two species of the herring family is highly variable, as
Finding: Biological
Impacts on Water Clarity are Increasingly Apparent
Because the AMP includes monitoring water quality and
biological parameters, it is possible to analyze the relative effects of
“bottom-up” (nutrient management) controls and “top-down” (food web) controls
on the lake’s trophic condition. Clearly, nutrient reductions at Metro have
affected the lake’s algal abundance, water clarity and DO concentrations. Food
web effects are also important, however, and now that
The alewife and dreissenid mussels have a major impact on
food web dynamics in
Figure EX- 13. Average zooplankton size (all taxa combined) and
alewife catch rates from electrofishing, 2000-2010,
Note: error bars are
standard error of the mean.
The loss of larger zooplankton, which are far more efficient grazers of phytoplankton, was evident in the 2010 algal community as well. Without the larger zooplankton to graze on phytoplankton, the standing crop increased and water clarity diminished (Figure EX-14).
Figure EX- 14. Mean Secchi disk depth measurements and mean
zooplankton size,
Finding: Monitored Locations in the
The 2010 data from the
County’s monitoring program indicate that bacterial levels at the monitoring
stations were less bacteria standards for contact recreation, except along the
southern shoreline following high rainfall and runoff conditions. The southern shoreline is in the Class C
segment of
For water clarity, the
NYSDOH has a swimming safety guidance value of 1.2 m (4 ft.) at designated
beaches. Secchi disk measurements at the
Class B nearshore stations were greater than the 1.2 m guidance value, while a
few incidences of diminished water clarity were detected at the Class C
stations along the southern shoreline in 2010. These incidences were associated
with high rainfall and runoff conditions.
Measuring Progress toward Improvement: Metrics
Onondaga
County Department of Water Environment Protection, in consultation with NYSDEC
and the Onondaga Lake Technical Advisory Group, has developed a suite of metrics
to help organize and report on the extensive AMP data set each
year. These metrics relate to the lake’s designated “best use” for water
contact recreation, fishing and protection of aquatic life. The 2010 results (Table EX-1) document that
water quality conditions fully support the lake’s designated uses in the Class
B segment.
Metrics |
Measured By |
Target |
2010 Results |
Significance |
|
Improved
Suitability for Water Contact Recreation |
|||||
Indicator
bacteria |
Percent of months in
compliance with AWQS1 for fecal colilform bacteria and with federal
criteria for E. coli, April – October (disinfection period). Measured
at nearshore sites, Class B segment |
100% (both indicators) |
100% (both indicators) |
Class B segments of |
|
Water
clarity |
Percent of observations with Secchi disk
transparency at least 1.2 m (4 ft.) to meet swimming safety guidance2,
June – Sept (recreational period).
Measured at nearshore sites, Class B segment |
100% |
100% |
||
Improved Aesthetic Appeal |
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Water
clarity |
Summer average Secchi disk transparency at least 1.5
m Measured at South Deep during the summer
recreational period (June- Sept.). |
Summer average 1.5 m |
Summer average 1.9 m |
By these metrics, the lake met its designated use as
an aesthetic resource |
|
Algal
blooms |
Algal abundance low in summer and the lake is free
of nuisance algal blooms3. Measured by the magnitude, frequency and
duration of elevated chlorophyll-a during the summer recreational period
(June- Sept). |
No more than 15% of chlorophyll –a measurements are
above 15 ppb; no more than 10% of observations are above 30 ppb |
100% of observations less than 15 ppb |
||
Algal community structure |
Low abundance of cyanobacteria (blue-green algae) |
Cyanobacteria represent no more than 10% of the
algal biomass |
Cyanobacteria were less than 1% of the algal biomass |
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Improved Aquatic Life Protection |
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Ammonia
|
In-lake Ammonia N concentrations compared to AWQS1 |
100% of measurements in compliance, all depths and
all times |
100% of measurements in compliance, all depths and
all times |
By these metrics, the lake met its designated use
for aquatic life protection (warm water fishery) |
|
Nitrite
|
In-lake Nitrite N concentrations1 (upper waters) |
100% |
100% |
||
Dissolved
oxygen |
Daily average during fall turnover1 Instantaneous minimum1 |
>5 mg/l >4 mg/l |
7.6 mg/l 7.4 mg/l |
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Improving Sustainable Recreational Fishery |
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Habitat
quality |
Percent of the littoral zone that is covered by
macrophytes |
40% |
54% |
Littoral zone macrophyte coverage provides high
quality habitat for warm water fish community |
|
Fish
reproduction |
Reproduction of target species: ·
Bass and
sunfish ·
yellow perch ·
black crappie ·
rock bass ·
walleye and
northern pike |
Occurring Occurring Occurring Occurring Occurring |
Occurring No evidence No evidence No evidence No evidence |
Fish reproduction for several target species has not
been observed. Adult population of
these species are stable and, in some cases, increasing. |
|
|
The lack of
suitable spawning habitat, not water quality, is the limiting factor for the
reproduction of some fish
species in the lake. Habitat
restoration and enhancement are included in the Honeywell lake restoration
efforts. |
||||
Fish community structure |
Percent of fish species intolerant or moderately intolerant of pollution |
Increasing presence of fish species sensitive to
pollution |
4% |
The |
|
1Ambient water
quality standards (AWQS), criteria and guidance regulatory citations are as
follows: · E. coli Ambient Water Quality Criteria for Bacteria 1986
- EPA440/5-84-002, (http://water.epa.gov/type/oceb/beaches/upload/2009_04_13_beaches_1986crit.pdf) · fecal coliform bacteria 6 NYCRR Part 703.4 (http://www.dec.ny.gov/regs/4590.html#16133) · ammonia-N and nitrite-N 6 NYCRR Part 703.5 (http://www.dec.ny.gov/regs/4590.html#16130) · dissolved oxygen 6 NYCRR Part 703.3 (http://www.dec.ny.gov/regs/4590.html#16132) 2Secchi depth water clarity swimming safety guidance
of 4 ft. NYSDOH Title 10, Section 7-2.11 - Recreational safety (http://www.health.ny.gov/nysdoh/phforum/) 3Algal blooms defined as “impaired”
at >15 ug/l (USEPA threshold for public perception as impaired for
recreational use); defined as “nuisance” at >30 ug/l (threshold for public
perception of nuisance bloom, Restoration and Management of Lakes and
Reservoirs by G.D. Cooke) Biological metrics were developed in
consultation with members of the Onondaga Lake Technical Advisory Committee
and other stakeholders participating in the annual meetings and reviews. |
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2010
ANNUAL REPORT
The 2010 Annual Ambient Monitoring Program
(AMP) report has been prepared and submitted to the New York State Department
of Environmental Conservation (NYSDEC) to comply with a judicial requirement
set forth in the 1998 Amended Consent Judgment (ACJ) between
NYSDEC classifies surface waters,
including lakes, rivers, streams, embayments, estuaries and groundwater with
respect to their best use.
Figure 1‑1. Tributary and lake regulatory
classifications and subwatershed boundaries.
Onondaga
County WEP designed the AMP to meet several specific objectives related to the
effectiveness of the required improvements to the wastewater collection and
treatment infrastructure. Trained field technicians
collect representative samples from a network of permanent sampling locations
along the lake tributaries, nearshore and deep stations in Onondaga Lake (Figure 1-2), and along the Seneca River
(see Figure 7-1, in Section 7),
and evaluate water quality conditions and the nature of the biological
community. These data are interpreted to
determine whether designated uses are, in fact, supported in the waterways.
In addition
to the overall assessment of use attainment,
·
to identify sources of materials (nutrients, sediment, bacteria
and chemicals) entering the lake,
·
to evaluate stream
and lake water quality conditions with respect to compliance with ambient water
quality standards (AWQS) and guidance values,
·
to understand the
interactions between
·
to track the nature
of the biological community, and
·
to support
development of mechanistic models for managing water quality conditions.
A Data Analysis and Interpretation Plan (DAIP) (Table 1-1) guides program design and is
a component of the annual workplan, and thus
subject to NYSDEC review and approval. In addition to approving the annual
workplan and AMP report, NYSDEC participates in technical discussions of the
AMP results and their implications.
Each year,
The ACJ directs
Table 1‑1. Overview of AMP data analysis and interpretation plan. |
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Parameters |
Sampling
Locations |
Compliance |
TMDL
Analysis |
Trend
Analysis |
Trophic
Status |
Load
Analysis |
Model
Support |
Use
Attainment |
Effectiveness
of CSO control
measures |
Indicator
of Water
Clarity |
Nutrient
Cycling |
Habitat
Conditions |
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Chemical |
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Alkalinity |
L, T |
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Bacteria |
L, T |
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BOD-5 |
L, T, R |
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Carbon |
L, T, R |
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Mercury |
L, T |
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Metals/Salts |
L, T, R |
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Nitrogen |
L, T, R |
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Phosphorus |
L, T, R |
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Silica |
L |
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Solids |
L, T, R |
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Sulfides |
L |
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Physical |
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Conductivity |
L, T, R |
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Dissolved oxygen |
L, T, R |
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LiCor illumination |
L, R |
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Salinity |
L, T, R |
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Secchi transparency |
L, R |
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Turbidity |
L, T, R |
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Biological |
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Chlorophyll/algae |
L, T, R |
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Zooplankton |
L |
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Macrophytes |
L |
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Macroinvertebrates |
L, T |
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Fish |
L |
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Locations: L = Lake; T =
Tributaries; R = Seneca River. |
The ACJ stipulates a series of specific
engineering improvements to the County’s wastewater collection and treatment
infrastructure.
Other remedial programs abate the impacts of
combined sewer overflows (Table 1-3). Combined sewer overflows (CSOs) serve older portions of the
City of
Table 1‑2. Metro compliance schedule. (lb/d =
pounds per day; mg/l = milligrams per liter) |
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Parameter |
SPDES Limit |
Effective Date |
Achieved Date |
Ammonia |
Stage I : 8,700 lb/d (7/1-9/30) 13,100 lb/d (10/1-6/30) |
January 1998 |
January 1998 |
|
Stage II: 2 mg/l (6/1-10/31) 4 mg/l (11/1-5/31) |
May 2004 |
February 2004 |
|
Stage III: 1.2 mg/l (6/1-10/31) 2.4 mg/l (11/1-5/31) |
December 2012 |
February 2004 |
Total Phosphorus |
Stage I : 400 lb/d (12-month rolling average) |
January 1998 |
January 1998 |
|
Stage II: 0.12 mg/l (12-month rolling average) |
April 2006 |
April 2006 |
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Revised Interim Stage II: 0.10 mg/l (12-month rolling average) |
November 2010 |
November 2010 |
|
Stage III: 0.020 mg/l (or as modified by TMDL) |
December 2015 (or as modified by TMDL) |
Pending |
Table 1‑3. CSO compliance schedule. |
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Project Phase |
Goal |
Effective Date |
Stage I |
Capture
for treatment or eliminate 89.5% of combined sewage* during precipitation, within the meaning of EPA’s National CSO Control
Policy |
Dec
31, 2013 |
Stage II |
Capture for
treatment or eliminate 91.4% of combined sewage during precipitation, within the meaning of EPA’s National CSO Control
Policy |
Dec
31, 2015 |
Stage III |
Capture
for treatment or eliminate 93% of combined sewage during precipitation within the meaning of EPA’s National CSO Control
Policy |
Dec
31, 2016 |
Stage IV |
Capture
for treatment or eliminate 95% of combined sewage during precipitation within the meaning of EPA’s National CSO Control
Policy |
Dec
31, 2018 |
*on a system-wide annual average basis (per fourth
stipulation to ACJ, Nov. 2009) |
Honeywell International is proceeding with
a number of projects to address industrial contamination issues, with oversight by the
federal Environmental Protection Agency (EPA) and NYSDEC. Projects include
intercepting and treating contaminated
groundwater, removing contaminated sediments and restoring shoreline and
littoral habitats. Detailed descriptions of Honeywell’s planned remedial
projects, designed to prevent the flux of contamination into the lake and
restore aquatic habitat, are on the NYSDEC web site http://www.dec.ny.gov/chemical/48828.html.
·
water contact recreation;
·
aesthetics;
·
aquatic life protection; and
·
sustainable recreational fishery.
In addition
to the annual snapshot provided in the table of metrics, series of more detailed
tables are prepared to describe progress toward improvement with respect to specific water quality and biological
attributes of
The
Figure 2‑1. Annual average inflows to Onondaga Lake, 2001-2010.
Each year, the tributaries convey surface runoff and groundwater
seepage from the large watershed toward
Compared with other lakes in the Seneca-Oneida-Oswego river basin,
the watershed of
Figure 2‑2. Land cover
classification map.
Figure 2‑3. Bathymetric
map.
The
Because
By signing the ACJ in 1998,
Abating the CSOs is a significant challenge. The County has employed four strategies to reduce wet weather discharges from the combined sewer system to the Metro treatment plant; these methods include separating sewers, constructing regional treatment facilities, capturing floatable materials and maximizing system storage capacity (Figure 3-1), or “gray infrastructure” (Table 3-2). In 1998, there were 70 active CSOs in the collection system. The ACJ projects have closed or minimized 32 of these collection system overflow points, by separating combined sewers where feasible, maximizing the capacity of the sewerage system, building the Hiawatha and Midland regional treatment facilities, and installing six floatable control facilities.
County facilities and
other urban areas have begun to implement “green infrastructure” solutions to
help manage urban storm runoff before it enters the CSO system. Green infrastructure encourages infiltration,
capture and reuse of storm runoff before it enters the sewer system. By the end of 2010, construction was completed
on 37 green infrastructure projects; these projects included replacement of
traditional pavement with porous pavement in parking lots, construction of
vegetated roofs, installation of rain barrels and infiltration trenches,
removal of pavement from some areas, and other techniques to reduce storm water
runoff. By preventing storm water runoff
from entering the combined sewers, more capacity is available for sanitary
sewage flow to reach Metro for treatment.
A “Save the Rain” initiative is underway to educate watershed residents
about ways to capture and use rainwater.
An informational website describes current initiatives and incentive
programs for watershed residents to reduce impervious areas http://savetherain.us/.
|
Table 3‑1. Summary (timeline) of significant
milestones and pollution abatement actions and lake water quality
conditions. |
|||||
Year |
Regulatory/ Management Actions |
Metro Actions |
CSO Abatement Actions |
Water Quality Achievements |
Biological Response |
|
1998 |
Amended
Consent Judgment (ACJ) signed |
Cap
on annual ammonia and phosphorus load to the lake, begin selection and design
of improvements |
Evaluation
and implementation of nine minimum
control measures |
Summer
TP 55 µg/l in lake’s upper waters |
County
begins design of integrated biological monitoring program |
|
1999 |
|
Completed
upgrade of aeration system for secondary clarifiers at Metro |
Maltbie
Floatables Control Facility (FCF) |
|
|
|
2000 |
|
|
Harbor
Brook Interim FCF |
|
Biological
AMP begins Littoral
zone plant coverage in June: 11%. |
|
2001 |
|
|
Teall
FCF Hiawatha
Regional Treatment Facility (RTF) |
|
|
|
2002 |
|
|
Erie
Blvd Storage System repairs completed Kirkpatrick
St. Pump Station Upgrade |
|
Strong
alewife year class followed by declines in large zooplankton |
|
2003 |
Three
Rivers Water Quality Model peer review completed |
|
Progress
with sewer separation (refer
to 2009) |
Compliance
with AWQS for DO in lake upper waters during fall |
|
|
2004 |
|
Year-round
nitrification of ammonia at Metro using BAF; Stage III SPDES limit for
ammonia met. |
Progress
with sewer separations (refer to 2009) |
Compliance
with AWQS for ammonia in lake upper waters, and for fecal coliform bacteria
in |
|
|
2005 |
|
Actiflo®
system on-line to meet Metro Stage II SPDES limit for TP (0.12 mg/l) |
Progress
with sewer separations (refer to 2009) |
|
No
summer algal blooms Littoral
zone plant coverage in June: 49%. |
|
2006 |
ACJ
Amendment motion filed by NYS Attorney General's Office |
|
Progress
with sewer separations (refer to 2009) |
Compliance
with AWQS for nitrite in the lake’s upper waters |
|
|
2007 |
|
Metro
meets Stage 2 SPDES limit for TP on schedule. Onondaga
Lake Water Quality Model development/calibration review (Phase 2). |
Progress
with sewer separations (refer to 2009) |
Compliance
with AWQS for ammonia in the lake, all depths Summer
TP 25 µg/l in lake’s upper waters |
Mesotrophic
conditions achieved |
|
2008 |
|
|
Midland
Ave. Phase I and II conveyance, storage and RTF |
Summer
TP 15 µg/l in lake’s upper waters |
Alewife
population decline followed by resurgence of large zooplankton |
|
2009 |
ACJ
amended by Stipulation #4. |
|
Green
Infrastructure (GI) program begins 13
sewer separation projects completed 1999- 2009 |
Summer
TP 17 µg/l in lake’s upper waters |
Strong
alewife year class |
|
2010 |
|
Compliance
with interim Stage II TP limit of 0.10 mg/l |
Harbor
Brook Interceptor replacement Close
to 40 GI projects complete by 2010, converting approx. 16.7 acres of
impervious surfaces |
Summer
TP 25 µg/l in lake’s upper waters |
Resurgence
of alewife; loss of larger zooplankton |
|
Figure 3‑1. Map of CSO areas.
Table
3‑2. CSO
remedial projects (gray infrastructure) planned. |
|||
Receiving
Water/ CSO service
area |
Affected CSO Outfalls |
Facility (pending approval of facility plans) |
Completion Date |
Harbor Brook |
014, 015 and 017 |
Interceptor
replacement |
12/31/2010 |
|
018 |
Wetlands
treatment with floatables control |
12/31/2013 |
Lower Harbor Brook |
003, 004 |
3.7
million gallon storage tank |
12/13/2013 |
Onondaga Creek/ |
030,
034 |
6.0
million gallon storage tank |
12/31/2013 |
Onondaga Creek/ |
052, 060/077 |
In design, anticipated that overflows will be captured by Midland
RTF |
12/31/2018 |
Precipitation in 2010 was a mixture of wet and
dry months in Syracuse. There was an overall
precipitation deficit of 4.3 inches from January through May, followed by a
precipitation surplus of 8.2 inches for the period from June through September.
Total precipitation for the year was 41.47 inches, above the 30- year average
(1980 – 2009) of 38.02 inches.
June was the wettest month; April was the driest. The winter (2009-2010) had lower than average
snowfall; 106 inches were recorded which is less than the long-term average of
121 inches.
Despite these
variations, the average 2010 precipitation and
temperature patterns were consistent with those measured
over the previous 30 years. The climatic
conditions were reflected in the streamflow conditions; streamflow conditions in the major
tributaries remained close to long-term average conditions, with discharge
spikes in late winter and June, and additional spikes from storms later in the
summer.
Several
segments of
AMP
data confirmed exceedances of standards of AWQS for fecal coliform bacteria in
2010 in the influent streams, except for Tributary 5A at
The abundance of
fecal coliform bacteria in the lake tributaries during wet weather is affected
by stormwater runoff and functioning of the combined sewer system. CSO remedial measures and improved stormwater
management measures are underway. Among
the objectives of the AMP is to track changes in the inflow of bacteria to
To help meet these
two related objectives, bacterial quality of the CSO-affected streams is
evaluated at both low flow and high flow conditions by segregating the data set
based on antecedent precipitation. The
detailed storm sampling results confirm that wet weather conditions transport
substantial loads of bacteria to the lake, especially from the CSO-affected
tributaries. The impact of wet weather on bacterial abundance is seen in the
nearshore lake data as well; this is discussed further in Section 5.7. Spikes in the abundance of
bacteria occur during storms and typically occur for limited time duration. The
biweekly monitoring program, which is supplemented by high flow event
monitoring, does not capture every storm. As a result, the annual load
estimates are associated with a high standard error (low precision), due to the
variability in the measurements. For example, a simple segregation of the
annual bacterial loads into wet years and dry years does not reveal a
consistent annual pattern; wet years are not always associated with higher
annual loading estimates. This is likely due to the sporadic nature of the
sources and the timing of sample collection. However, examining the individual
sampling results does confirm the significant impact of wet weather on
bacterial counts in the streams. Additional analysis of the bacteria data is
planned for the 2011 Annual AMP report.
Both Harbor Brook
and Onondaga Creek have stations upstream and downstream of the urban
CSO-affected corridor. Comparing these upstream and downstream
stations reveals changes in loading as the streams
flow through the urban corridor.
Ninemile Creek receives stormwater runoff from a separate sewer
system. As expected, fecal coliform bacteria
counts are higher when flows are higher and counts are elevated downstream of
CSOs. The abundance of fecal coliform
bacteria during summer low flow conditions is consistently higher downstream of the
urban corridor served by combined sewers.
Since CSOs are not active during dry weather conditions, the higher
concentrations observed downstream are not attributable to this source or to
storm runoff from the urban corridor. Seepage from damaged sewer pipes and
illicit connections of sanitary waste to the stormwater collection system are
potential sources. Urban wildlife is also a potential source, although the
urban downstream monitoring locations do not provide good wildlife habitat.
During 2010,
elevated fecal coliform bacteria counts in the tributaries were generally
associated with high flow (wet weather) conditions (Figure
4-1). Consistent with data
measured in previous years, fecal coliform bacterial counts were higher at
monitoring stations downstream of CSOs.
Wet weather fecal coliform bacteria counts were particularly elevated at
the downstream station (Hiawatha) on Harbor Brook in 2010.
Table 4‑1. Summary of tributary compliance with ambient water quality standards, 2010. (underlined
parameters are specified in the ACJ) |
||||||||||||||
Site |
Ammonia-N |
Arsenic |
Cadmium |
Chromium |
Copper |
Cyanide |
Dissolved Oxygen |
Fecal Coliform |
Lead |
Mercury |
Nickel |
Nitrite |
pH |
Zinc |
Allied East Flume |
57% |
100% |
100% |
100% |
100% |
100% |
100% >4; 96% >5 |
86% |
100% |
See note |
100% |
0% |
89% |
100% |
Bloody Brook at |
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 100% >5 |
0% |
100% |
|
100% |
100% |
100% |
100% |
Bloody Brook at |
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 100% >5 |
20% |
100% |
|
100% |
100% |
100% |
100% |
Harbor Brook at Hiawatha |
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 100% >5 |
25% |
100% |
|
100% |
100% |
96% |
100% |
Harbor Brook at Velasko |
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 100% >5 |
67% |
100% |
|
100% |
100% |
100% |
100% |
Ley Creek at Park |
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 94% >5 |
13% |
100% |
|
100% |
100% |
100% |
100% |
Ninemile Creek at |
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 100% >5 |
63% |
100% |
|
100% |
100% |
98% |
100% |
Onondaga Creek at Dorwin |
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 100% >5 |
50% |
100% |
|
100% |
96% |
100% |
100% |
Onondaga Creek at Kirkpatrick |
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 100% >5 |
11% |
100% |
|
100% |
100% |
100% |
100% |
|
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 100% >5 |
-- |
100% |
|
100% |
100% |
100% |
100% |
|
100% |
100% |
100% |
100% |
100% |
100% |
100% >4; 98% >5 |
100% |
100% |
|
100% |
100% |
100% |
100% |
Sawmill at |
100% |
100% |
100% |
100% |
100% |
100% |
95% >4; 91% >5 |
0% |
100% |
|
100% |
100% |
100% |
100% |
Tributary 5A at |
100% |
100% |
100% |
100% |
75% |
100% |
100% >4; 96% >5 |
100% |
100% |
|
100% |
96% |
100% |
100% |
Note on Mercury: Onondaga County laboratory received
certification for low-level mercury analysis as of June 1, 2010. The 2010
data set has two method reportable limits (equivalent to Practical
Quantitation Limits, PQL) for mercury:
0.02 µg/l (standard analysis) and 0.001 µg/l (ultra-low level
analysis). Both method reportable
limits are at least one order of magnitude greater than the AWQS of 0.0007
µg/l. In 2010, 72% of all tributary
samples were reported with results below the applicable method reportable
limit. Since the analytical methods cannot measure mercury at the level of
the AWQS, percent compliance with the AWQS cannot be assessed. |
The 2010 flow-weighted average concentrations of
total and soluble reactive phosphorus (TP and SRP), ammonia-N, TKN, total
suspended solids, fecal coliform bacteria and chloride measured in the
Table 4‑2. Flow-weighted average concentration of
selected parameters in Note: N represents
the number of samples included in the annual flow-weighted average
calculation. |
||||||||||||||
Parameter* |
TP |
SRP |
NH3-N |
TKN |
TSS |
Chloride |
F.Coli*** |
|||||||
Units |
µg/l (N) |
µg/l (N) |
mg/l (N) |
mg/l (N) |
mg/l (N) |
mg/l (N) |
cells/100ml (N) |
|||||||
Metro**: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Treated Effluent |
79 |
(363) |
3.6 |
(57) |
0.32 |
(363) |
1.2 |
(363) |
5.0 |
(363) |
387 |
(75) |
580 |
(211) |
By-pass |
1076 |
(43) |
347 |
(7) |
5.9 |
(43) |
10 |
(43) |
62 |
(43) |
245 |
(2) |
136,296 |
(39) |
Watershed: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Onondaga Creek |
148 |
(27) |
16 |
(27) |
0.057 |
(27) |
0.74 |
(27) |
80 |
(27) |
289 |
(27) |
2,582 |
(54) |
Ninemile Creek |
80 |
(27) |
16 |
(27) |
0.17 |
(27) |
0.70 |
(27) |
22 |
(27) |
224 |
(27) |
1,917 |
(53) |
Ley Creek |
72 |
(24) |
13 |
(24) |
0.20 |
(24) |
0.70 |
(24) |
13 |
(24) |
276 |
(24) |
1,004 |
(51) |
Harbor Brook |
65 |
(27) |
29 |
(27) |
0.052 |
(27) |
0.50 |
(27) |
12 |
(27) |
258 |
(27) |
3,210 |
(53) |
Tributary 5A |
101 |
(25) |
35 |
(25) |
0.15 |
(25) |
0.49 |
(25) |
15 |
(25) |
307 |
(25) |
61 |
(52) |
East Flume |
93 |
(23) |
20 |
(23) |
1.1 |
(23) |
1.8 |
(23) |
11 |
(23) |
693 |
(23) |
299 |
(46) |
Notes: Watershed tributary results
are reported for downstream sampling locations closest to Flow-weighted average concentrations were computed on each sampled
day using instantaneous flows for Storm Event samples and daily mean flows
for Routine samples. *Parameters: TP = Total
Phosphorus; SRP = Soluble Reactive Phosphorus; NH3-N = Ammonia as N; TKN
= Total Kjeldahl Nitrogen; TSS = Total
Suspended Solids; F.Coli = Fecal Coliform bacteria ** Metro: Treated effluent
NH3-N, TP, and TSS were based on daily measurements, SRP, chloride and F.Coli
were measured less frequently. Metro
By-pass was only sampled when active (during high flow events where the
capacity of the treatment plant was exceeded). *** Bacteria concentrations are highly variable. |
Of the monitored tributaries, Harbor
Brook exhibited the highest abundance of fecal coliform bacteria in 2010. In Ninemile Creek, which does not receive
CSOs, fecal coliform bacterial abundance was comparable to levels measured in
Onondaga Creek and Ley Creek. Onondaga Creek has active CSOs; outfalls on Ley
Creek are captured and directed to the Hiawatha RTF. This finding illustrates
the importance of non-CSO sources of bacteria over a range of precipitation and
streamflow regimes.
The 2010 loading of selected parameters (Table 4-3) illustrates the importance of the relative flow volume on total external loading of nutrients, sediment, chloride and bacteria to the lake. For example, while the flow-weighted average concentration of fecal coliform bacteria was highest in Harbor Brook, loading of fecal coliform bacteria from this source was lower than from other tributaries with higher flow. Dr. William Walker developed customized software for Onondaga County WEP staff to calculate annual loads using the program AUTOFLUX, method 5. This model uses the detailed flow record and results of water quality grab samples to generate the annual loading values presented in Table 4-3. Note that the significant figures in the table should not be interpreted as representing precision of the annual loading estimates.
Table
4‑3. Load
of selected nutrients, salts and bacteria to Notes: mt = metric tons. N represents the number of water quality
samples included in the annual load calculation. |
||||||||||||||
Parameter* |
TP |
SRP |
NH3-N |
TKN |
TSS |
Chloride |
F.Coli** |
|||||||
Units |
mt (N) |
mt (N) |
mt (N) |
mt (N) |
mt (N) |
mt (N) |
1010 cfu (N) |
|||||||
Metro: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Treated Effluent(1) |
6.6 |
(363) |
0.30 |
(57) |
26 |
(363) |
100 |
(363) |
417 |
(363) |
32169 |
(75) |
48,283 |
(211) |
By-pass(2) |
1.5 |
(43) |
0.49 |
(7) |
8.4 |
(43) |
14 |
(43) |
81 |
(43) |
348 |
(2) |
193,766 |
(39) |
Watershed: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Onondaga Creek |
25 |
(27) |
2.7 |
(27) |
9.7 |
(27) |
125 |
(27) |
13678 |
(27) |
49223 |
(27) |
439,632 |
(54) |
Ninemile Creek |
12 |
(27) |
2.4 |
(27) |
25 |
(27) |
105 |
(27) |
3234 |
(27) |
33286 |
(27) |
285,073 |
(53) |
Ley Creek |
2.8 |
(24) |
0.50 |
(24) |
7.7 |
(24) |
27 |
(24) |
502 |
(24) |
10583 |
(24) |
38,431 |
(51) |
Harbor Brook |
0.66 |
(27) |
0.30 |
(27) |
0.53 |
(27) |
5.0 |
(27) |
118 |
(27) |
2621 |
(27) |
32,637 |
(53) |
Tributary 5A |
0.092 |
(25) |
0.032 |
(25) |
0.13 |
(25) |
0.45 |
(25) |
13 |
(25) |
280 |
(25) |
56 |
(52) |
East Flume |
0.10 |
(23) |
0.023 |
(23) |
1.2 |
(23) |
2.0 |
(23) |
13 |
(23) |
774 |
(23) |
333 |
(46) |
Notes: Tributary
results are reported for downstream sampling locations closest to The
flow-weighted-mean concentration is computed for each day before being used
in computing loads. *Parameters: TP = Total Phosphorus; SRP = Soluble
Reactive Phosphorus; NH3-N = Ammonia as N; TKN = Total Kjeldahl Nitrogen; TSS
= Total Suspended Solids; F.Coli = Fecal Coliform bacteria. (1)
Metro Outfall 001 calculated loads of NH3-N, TP, TSS are based on daily
measurements; METRO TKN based on 5 measurements/2 wks (2)
Metro Bypass Outfall 002 estimates based on periodic grab samples when
outfall is active (high flow events where the capacity of the treatment plant
is exceeded). **
Fecal bacteria loads are associated with a very high standard error- i.e.,
they are imprecise, due to the episodic nature of the inputs. |
The percent of the total load attributed to each source is summarized in Table 4-4. Note that 2010 loading results for all measured parameters, as well as the historical loading (1990-2010) are included in the library of this report. The magnitude of TP load from non-Metro sources varies each year; annual rainfall influences the total loading from the watershed, with the highest nonpoint source loads evident in wet years (Figure 4-2). Note that the concentrations of total and soluble phosphorus are an order of magnitude higher in Outfall 002 (Metro bypass) as compared with the other sources. However, the small volume of this discharge on an annual basis results in a small overall contribution of this source to the annual loading (3.1 % of the TP and 7.3% of the SRP).
Table 4‑4. Percent annual loading contribution by gauged inflow, 2010. |
||||||||
Parameter |
TP |
SRP |
NH3-N |
TKN |
TSS |
Chloride |
F. coli bacteria |
Water |
Metro: |
|
|
|
|
|
|
|
|
Treated Effluent |
14% |
4.5% |
33% |
26% |
2.3% |
25% |
4.7% |
18% |
By-pass |
3.1% |
7.3% |
11% |
3.7% |
0.45% |
0.27% |
19% |
0.31% |
Watershed: |
|
|
|
|
|
|
|
|
Onondaga Creek |
52% |
39% |
12% |
33% |
76% |
38% |
42% |
37% |
Ninemile Creek |
24% |
36% |
32% |
28% |
18% |
26% |
27% |
33% |
Ley Creek |
5.6% |
7.4% |
10% |
7.1% |
2.8% |
8.2% |
3.7% |
8.4% |
Harbor Brook |
1.3% |
4.4% |
0.66% |
1.3% |
0.66% |
2.0% |
3.1% |
2.2% |
Tributary 5A |
0.19% |
0.47% |
0.16% |
0.12% |
0.07% |
0.22% |
0.005% |
0.20% |
East Flume |
0.21% |
0.33% |
1.6% |
0.52% |
0.071% |
0.60% |
0.032% |
0.25% |
|
|
|
|
|
|
|
|
|
Figure 4‑2. Watershed (non-Metro) TP annual load and annual rainfall, 1990-2010.
Data source for average annual rainfall http://www.nws.noaa.gov/climate/xmacis.phpwfo=bgm
Because
With the reduction in phosphorus load from Metro resulting from the Actiflo® system, the total external TP load to Onondaga Lake is lower, and watershed load is increasingly important (refer to Figure EX-6). The decrease in TP load is statistically significant. The relationship between the external phosphorus load and the summer average concentration at the South Deep station is illustrated in Figures EX-2 and EX-5, and is further discussed in Section 5.7.
Comparison of phosphorus loading before the ACJ (1990-1998) and after implementation of the Actiflo® system at Metro (2007-2010) indicates the magnitude of reduction in phosphorus loading realized by this technology (Tables 4-5, 4-6 and 4-7). The treatment technology has also converted much of the phosphorus into particulate forms that are not biologically available, as evident by the decline in SRP and TDP concentrations in the effluent.
As part of the development of the
Onondaga Lake Water Quality Model (OLWQM), the Onondaga Lake Partnership
contracted for testing the bioavailability of phosphorus (i.e., its potential
to stimulate algal growth) within Metro effluent and the lake’s major
tributaries. The 2009 bioassay studies
completed by UFI concluded that the particulate phosphorus within the Metro
effluent is bound up within iron-enriched solids, escaping the high rate
flocculation settling (HRFS) process; these solids were also found to settle
rapidly. The particles from the
tributaries are predominantly finer and remain suspended in the lake waters for
longer periods. The bioavailability
assays indicated that only 1% of the particle-bound phosphorus in the Metro
effluent is available for release into the water column to stimulate algal
growth.
Table
4‑5. Tributary
and Metro Total Phosphorus (TP) Loading to (mt = metric tons; concentrations
flow-weighted). |
||||||||
|
1990-1998 (pre-ACJ) |
2007-2010 (post-Actiflo®) |
||||||
SITE |
Flow |
TP |
TP |
TP |
Flow |
TP |
TP |
TP |
Metro: |
|
|
|
|
|
|
|
|
fully treated |
21% |
52 |
57% |
0.56 |
18% |
7.8 |
20% |
0.092 |
bypass |
0.94% |
8.5 |
7.5% |
1.8 |
0.35% |
2.0 |
5.1% |
1.2 |
Watershed: |
|
|
|
|
|
|
|
|
Onondaga Creek |
34% |
20 |
19% |
0.12 |
37% |
16 |
39% |
0.094 |
Ninemile Creek |
32% |
10 |
10% |
0.065 |
34% |
10 |
25% |
0.064 |
Ley Creek |
8.7% |
5.7 |
5.8% |
0.14 |
8.2% |
3.2 |
8.2% |
0.084 |
Harbor Brook |
2.1% |
0.71 |
0.71% |
0.070 |
2.4% |
1.1 |
2.8% |
0.092 |
Tributary 5A |
0.72% |
0.17 |
0.19% |
0.054 |
0.23% |
0.11 |
0.29% |
0.11 |
East Flume |
0.23% |
0.19 |
0.18% |
0.20 |
0.18% |
0.10 |
0.26% |
0.11 |
Summary |
100% |
97 |
100% |
0.38 |
100% |
40 |
100% |
0.23 |
Table
4‑6. Tributary
and Metro Soluble Reactive Phosphorus (SRP) Loading to (mt = metric tons; concentrations
flow-weighted). |
||||||||
|
1990-1998 (pre-ACJ) |
2007-2010 (post-Actiflo®) |
||||||
SITE |
Flow |
SRP |
SRP |
SRP |
Flow |
SRP |
SRP |
SRP |
Metro: |
|
|
|
|
|
|
|
|
fully treated |
21% |
12 |
59% |
0.13 |
18% |
0.30 |
5.8% |
0.004 |
bypass |
0.94% |
2.5 |
9.7% |
0.50 |
0.37% |
0.42 |
8.0% |
0.26 |
Watershed: |
|
|
|
|
|
|
|
|
Onondaga Creek |
34% |
3.3 |
16% |
0.021 |
37% |
1.8 |
34% |
0.011 |
Ninemile Creek |
32% |
1.7 |
7.9% |
0.011 |
34% |
1.7 |
32% |
0.011 |
Ley Creek |
8.7% |
1.4 |
6.1% |
0.033 |
8.3% |
0.53 |
11% |
0.014 |
Harbor Brook |
2.1% |
0.25 |
1.1% |
0.024 |
2.4% |
0.41 |
8.1% |
0.036 |
Tributary 5A |
0.72% |
0.030 |
0.17% |
0.010 |
0.22% |
0.033 |
0.66% |
0.032 |
East Flume |
0.23% |
0.065 |
0.29% |
0.092 |
0.21% |
0.031 |
0.61% |
0.033 |
Summary |
100% |
21 |
100% |
0.103 |
100% |
5.2 |
100% |
0.050 |
The improvements to Metro have also resulted in a statistically
significant reduction in the input of ammonia-N to
Table
4‑7. Tributary
and Metro Total Dissolved Phosphorus (TDP) Loading to (mt = metric tons; concentrations
flow-weighted). |
||||||||
|
1990-1998 (pre-ACJ) |
2007-2010 (post-Actiflo®) |
||||||
SITE |
Flow |
TDP |
TDP |
TDP |
Flow |
TDP |
TDP |
TDP |
Metro: |
|
|
|
|
|
|
|
|
fully treated |
21% |
na |
na |
na |
18% |
2.3 |
22% |
0.028 |
bypass |
0.94% |
na |
na |
na |
0.37% |
0.58 |
5.3% |
0.36 |
Watershed: |
|
|
|
|
|
|
|
|
Onondaga Creek |
34% |
na |
na |
na |
37% |
2.7 |
25% |
0.016 |
Ninemile Creek |
32% |
na |
na |
na |
34% |
3.8 |
33% |
0.024 |
Ley Creek |
8.7% |
na |
na |
na |
8.3% |
0.93 |
9.0% |
0.024 |
Harbor Brook |
2.1% |
na |
na |
na |
2.4% |
0.48 |
4.4% |
0.042 |
Tributary 5A |
0.72% |
na |
na |
na |
0.22% |
0.044 |
0.44% |
0.044 |
East Flume |
0.23% |
na |
na |
na |
0.21% |
0.053 |
0.51% |
0.055 |
Summary |
100% |
na |
na |
na |
100% |
10.9 |
100% |
0.074 |
A statistical analysis of the prior ten years of tributary
data (Table 4-8) documents increasing and
decreasing trends in several important water quality parameters. Ammonia-N (NH3-N) concentrations exhibited
decreasing trends over the 2001-2010 period, and chloride concentrations
exhibited increasing trends, at five of the ten monitoring locations. Total P
concentrations increased at Metro bypass, the
Increasing concentrations of salts are evident at several monitoring locations as well. These increases are consistent with a USGS conceptual model of changes to regional groundwater salinity, as reported by William Kappel to the OLTAC (see also Yager, Kappel and Plummer 2007).
Table
4‑8. Ten-year
trends in tributary concentrations (2001-2010) – summary. |
|||||||||||
|
|
Metro |
Onondaga Creek |
Harbor Brook |
Ley Creek |
Ninemile Creek |
|
|
|||
Variable |
|
Treated Effluent |
By-pass |
Dorwin |
Kirkpatrick |
Velasko |
Hiawatha |
Park |
Route 48 |
Tributary 5A |
East Flume |
Nitrogen |
Ammonia-N (NH3-N) |
↓ |
○ |
↓ |
↓ |
↓ |
↓ |
○ |
↓ |
○ |
○ |
|
Nitrite-N (NO2-N) |
↓ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
|
Nitrate-N (NO3-N) |
↑ |
○ |
○ |
↓ |
○ |
○ |
↓ |
↓ |
○ |
○ |
|
Organic Nitrogen |
↓ |
○ |
○ |
○ |
↑ |
○ |
↓ |
○ |
○ |
↓ |
|
Total Kjeldahl Nitrogen (TKN) |
↓ |
○ |
○ |
○ |
○ |
○ |
↓ |
↓ |
○ |
○ |
Phosphorus |
Total Phosphorus (TP) |
↓ |
↑ |
↑ |
○ |
○ |
↑ |
↓ |
○ |
○ |
↓ |
|
Soluble Reactive Phosphorus (SRP) |
↓ |
○ |
↑ |
○ |
○ |
↑ |
↓ |
○ |
↓ |
↓ |
Solids |
Total Suspended Solids (TSS) |
↓ |
○ |
↑ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
|
Total Dissolved Solids (TDS) |
↑ |
○ |
○ |
○ |
↑ |
○ |
↑ |
↓ |
↓ |
○ |
|
Volatile Suspended Solids (VSS) |
○ |
○ |
- |
- |
- |
- |
- |
- |
- |
- |
Carbon |
Total Inorganic Carbon (TIC) |
↓ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↑ |
○ |
|
Total Organic Carbon (TOC) |
↓ |
○ |
○ |
○ |
↓ |
↓ |
○ |
○ |
○ |
↓ |
|
Total Organic Carbon, filtered (TOC_F) |
↓ |
○ |
○ |
○ |
↓ |
○ |
○ |
○ |
○ |
↓ |
Other |
Alkalinity |
↓ |
○ |
○ |
○ |
↑ |
○ |
↑ |
○ |
↑ |
|
|
BOD5* |
↓ |
○ |
- |
- |
- |
- |
- |
- |
- |
- |
|
Calcium (Ca) |
↑ |
○ |
○ |
○ |
↑ |
○ |
↑ |
↓ |
○ |
○ |
|
Chloride (Cl) |
↑ |
○ |
○ |
○ |
↑ |
↑ |
↑ |
↓ |
↓ |
↑ |
|
Conductivity |
○ |
○ |
○ |
○ |
↑ |
○ |
↑ |
↓ |
↓ |
↑ |
|
Dissolved Oxygen (DO) |
○ |
○ |
○ |
○ |
○ |
↑ |
○ |
○ |
○ |
○ |
|
Fecal Coliform Bacteria |
○ |
○ |
↑ |
○ |
○ |
○ |
○ |
↑ |
○ |
○ |
|
Hardness |
↑ |
○ |
○ |
○ |
↑ |
○ |
↑ |
↓ |
○ |
○ |
|
Magnesium (Mg) |
○ |
○ |
○ |
○ |
○ |
○ |
↑ |
↓ |
↓ |
↓ |
|
Sodium (Na) |
○ |
○ |
○ |
○ |
↑ |
↑ |
↑ |
↓ |
↓ |
↑ |
|
pH |
○ |
○ |
○ |
○ |
○ |
↑ |
○ |
↑ |
↑ |
↓ |
|
Silica (SiO2) |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↑ |
○ |
|
Sulfates (SO4) |
○ |
○ |
○ |
↓ |
○ |
○ |
○ |
○ |
↓ |
○ |
|
Temperature |
○ |
○ |
○ |
○ |
↓ |
○ |
○ |
○ |
○ |
○ |
Notes: Significance
level, two-tailed, seasonal ↓ indicates decreasing trend (p > 0.1) ↑ indicates increasing trend (p < 0.1) ○ indicates no trend (p = 0.1) - Dash indicates parameter is
not measured at this location. *BOD5 (Biochemical Oxygen Demand (5-day)) trend analysis results are accurate only for METRO & BYPASS because of the preponderance of data less than the MRL (PQL) in other inputs. |
On a loading basis (Table 4-9),
the treated effluent from Metro exhibited decreasing or stable trends for each
of the measured parameters except for nitrate-N (NO3-N). An increase in NO3-N is consistent
with the implementation of year-round nitrification in 2004. In Tributary 5A, loading of nearly all
measured parameters – except fecal coliform bacteria and solids (TSS) –
exhibited decreasing trends; in contrast, the East Flume exhibited increasing
trends for all but fecal coliform bacteria, organic carbon, phosphorus and
solids. Note that the loading of TP in both Onondaga Creek and Ninemile Creek
has increased over the decade; this increase is considered likely to be the
result of increasing rainfall and intensity of storms over this period. The
increased loading of suspended solids in Onondaga Creek is attributed to the
resurgence of mud boil activity in the
Table
4‑9. Ten-year
trends in tributary loading (2001-2010) – summary. |
|||||||||||
|
|
Metro |
Onondaga Creek |
Harbor Brook |
Ley Creek |
Ninemile Creek |
|
|
|||
Variable |
|
Treated Effluent |
By-pass |
Dorwin |
Kirkpatrick |
Velasko |
Hiawatha |
Park |
Route 48 |
Tributary 5A |
East Flume |
Nitrogen |
Ammonia-N (NH3-N) |
↓ |
○ |
↓ |
↓ |
↓ |
↓ |
↓ |
○ |
↓ |
↑ |
|
Nitrite-N (NO2-N) |
↓ |
○ |
↑ |
↑ |
○ |
○ |
○ |
○ |
↓ |
↑ |
|
Nitrate-N (NO3-N) |
↑ |
↓ |
○ |
○ |
○ |
○ |
↓ |
○ |
↓ |
↑ |
|
Total Kjeldahl
Nitrogen (TKN) |
↓ |
○ |
↑ |
○ |
○ |
○ |
↓ |
○ |
↓ |
↑ |
Phosphorus |
Total Phosphorus (TP) |
↓ |
○ |
↑ |
↑ |
○ |
○ |
○ |
↑ |
↓ |
○ |
|
Soluble Reactive
Phosphorus (SRP) |
○ |
○ |
↑ |
↑ |
○ |
○ |
○ |
↑ |
↓ |
○ |
Solids |
Total Suspended
Solids (TSS) |
↓ |
○ |
↑ |
↑ |
○ |
○ |
○ |
○ |
○ |
○ |
Carbon |
Total Inorganic
Carbon (TIC) |
↓ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
↑ |
|
Total Organic Carbon
(TOC) |
↓ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
○ |
|
Total Organic Carbon,
filtered (TOC_F) |
↓ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
○ |
Other |
Alkalinity |
↓ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
↑ |
|
BOD5* |
↓ |
○ |
- |
- |
- |
- |
- |
- |
- |
- |
|
Calcium (Ca) |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
↑ |
|
Chloride (Cl) |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
↓ |
↑ |
|
Fecal Coliform
Bacteria |
↓ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
|
Sodium (Na) |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
↑ |
|
Silica (SiO2) |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
↓ |
↑ |
Notes: Significance level, two-tailed, seasonal * BOD5 trend analysis results are
accurate only for METRO & BYPASS because of the preponderance of data
less than the MRL (PQL) in other inputs. |
Macroinvertebrates are an important component of the aquatic food web. Because they have limited migration patterns or a sessile mode of life, they are well suited for assessing site-specific impacts of point and nonpoint discharges. Many state agencies, including NYSDEC, use macroinvertebrate community structure as an indicator of the biological health of surface waters.
Macroinvertebrate sampling is among the requirements of the
ACJ;
Three metrics are calculated to analyze the tributary data: 1) NYSDEC Biological Assessment Profiles (BAP), an index of overall impact on the macroinvertebrate community; 2) the Hilsenhoff Biotic Index (HBI), a measure of community impairment due to organic enrichment; and 3) the percent contribution of oligochaetes to the macroinvertebrate community, another measure of organic enrichment from sewage or animal wastes. In addition, the NYSDEC Impact Source Determination (ISD) is calculated to determine the primary factor(s) affecting community structure. In 2010, the extent of deformities of certain Chironomidea (midge) species was evaluated; the incidence of deformities is used as an indicator of potential sediment toxicity.
Results of the AMP macroinvertebrate monitoring program indicate no consistent trends toward improving conditions in the monitored portions of the watershed since monitoring began in 2000 (Figure 4-3). Some individual sites have shown varying levels of change, both positive and negative, with no apparent relation to CSO abatement projects. All ten of the monitoring locations show some level of impact, though those in the upper portions of the watersheds are generally less impaired. Impairment is greatest in the lower portions of Ley Creek and Harbor Brook. ISD analyses indicate that the primary causes of impairment include excessive organic loading, primarily from sewage or animal wastes, and influences from municipal/industrial development. The macroinvertebrate community has been quite stable over the period of the AMP, despite some changes in land use and land cover in the subwatersheds.
Figure 4‑3. Biological
assessment designations,
Sites on Onondaga Creek showed a wide range of conditions in 2010 with a trend towards increasing impacts downstream (refer to Figure 1 in L05.9 report). This downstream trend has been evident since 2000, and is likely related to downstream increases in loading due first to changes from forested to agricultural land use in the upper watershed followed by a shift to urban land use downstream. Impacts to the macroinvertebrate community are generally slight upstream (Sites 1, 2 and 3) of urban areas and CSOs and moderate downstream (Site 4) of urban areas and CSOs.
Ley Creek tends to show the greatest degree of overall
impact of the three
Sites on Harbor Brook ranged from moderately to severely impacted based on BAP scores (refer
to Figure 3 in L05.9). The two sites
downstream of the most highly urbanized areas and all CSOs showed a greater
degree of impact than the upstream reference site.
There were too few chironomid
larvae in the 2010 tributary samples to support a statistical evaluation of
whether the percent of deformities exceeds what researchers consider as natural
background (approximately 3%). Results
of the 2010 analyses (Table 4-10) suggest that the percent of chironomid deformities in the
tributaries was relatively low, and consistent with a finding of no sediment
toxicity for the Onondaga Creek and Harbor Brook sites. Along Ley Creek, the
incidence of chironomid deformities detected at the
Table 4‑10. Incidence of chironomid deformities, |
|
Sampling Location |
Average
Percent of Chironomids with Deformities
(N) |
Onondaga Creek |
|
Tully Farms |
1.7 (16) |
|
6.1 (5) |
|
2.5 (35) |
|
3.1 (13) |
|
|
Harbor Brook |
|
|
0 (5) |
|
0 (5) |
Route 690 |
3.1 (13) |
|
|
Ley Creek |
|
|
6.9 (30) |
7th
|
21.6 (12) |
|
15.6 (10) |
Notes: 1.
The maximum
number of Chironomidae found in any of the 2010 tributary samples with
deformed Chironomidae was 48 (Ley Creek, 7th 2.
(N)
represents average number of Chironomidae in samples from each site. |
Effluent ammonia N remained well below the seasonal limits of 1.2 mg/l (June 1 to October 31) and 2.4 mg/l (November 1 to May 31), as displayed in Figure 4-4. Phosphorus concentrations were also consistently low throughout 2010 (Figure 4-5). As part of the November 2009, fourth stipulation to the ACJ, the interim Stage II TP effluent limit became 0.10 mg/l. Compliance with the revised interim limit, which is expressed as a 12-month rolling average, was evaluated beginning in November 2010.
Figure 4‑4. Metro NH3-N, 2010 effluent concentration compared to permit limits.
Figure 4‑5. Metro
TP, 2010 effluent concentration compared to permit limit.
During 2010, Outfall 002
activated on 42 occasions, for a cumulative duration of 314 hours. As a
result of the discharge through Outfall 002, a total of 374 million gallons of
wastewater reached
Documentation of combined sewer
overflows (CSOs) and sanitary sewer overflows (SSOs) throughout the
Trained WEP technicians collect samples from
The lake’s main sampling station, referred to as South Deep,
is the deepest point in the southern basin; this has been the standard
monitoring location on
During the summer, the AMP includes sampling at a network of nine near-shore locations for parameters indicative of the lake’s suitability for water contact recreation. These parameters include Secchi disk transparency, turbidity and fecal coliform bacteria.
The 2010 monitoring results indicate that
In addition, the summer 2010 total phosphorus (TP)
concentration in the lake’s upper waters (25 µg/l)
was above the state’s guidance value.
NYS has promulgated a narrative standard for phosphorus in water: “None in amounts that will result in growths
of algae, weeds and slimes that will impair the waters for their best usages”
(NYSCRR §703.2). For ponded waters, such
as
Onondaga County WEP collected water samples at two depths (3
m and 18 m) on three dates in 2010 and submitted the samples to Frontier Global
Sciences Inc. for ultra-low level measurement of total mercury using EPA method
1631, and for methyl mercury using EPA Method 1669. The AWQS for total Hg in
Class B and C waters is 0.7 ng/L. All six of the 2010
Onondaga Lake total Hg results exceeded this standard. The time
series of total Hg and methyl Hg data measured in both the upper and lower
waters of
The AMP further documented that dissolved oxygen (DO)
concentrations were not in 100% compliance with AWQS in 2012; DO in the lower
waters were below the minimum 4 mg/l during the summer stratified period. During
2010 fall mixing, Onondaga Lake DO concentrations in the upper waters met
the AWQS. Seasonal anoxia in stratified
lakes is common; in NY, an estimated 70% of assessed lakes do not meet the
minimum DO standards in the deep waters (NYSDEC Consolidated Assessment and
Listing Methodology, May 2009). NYSDEC
has not classified
In 2010, the measured fecal coliform bacteria counts at the Onondaga Lake monitoring stations did not exceed the ambient water quality standard (200 cfu/100mL) at offshore locations or at nearshore locations within the Class B water. For nearshore locations within the Class C water segment, monthly geometric mean concentrations of fecal coliform bacteria were within the ambient water quality standard of 200 cfu/100mL except at two locations (monthly standard not met 86% and 43% of the assessment period, refer to Figure 5-6).
Table 5‑1.
Parameters
listed in bold are cited in the ACJ.
|
South Deep |
Nearshore Stations |
||
|
Upper Mixed Layer |
Lower Water Layer |
|
|
Parameter |
(0-6m) |
(9-18m) |
(Class B) |
(Class C) |
Ammonia-N |
100% |
100% |
- |
- |
Arsenic |
100% |
100% |
- |
- |
Cadmium |
100% |
100% |
- |
- |
Chromium |
100% |
100% |
- |
- |
Copper |
100% |
100% |
- |
- |
Dissolved Oxygen |
100% >5 mg/l; 99.9% >4 mg/l |
76% >5 mg/l; 82% >4 mg/l |
- |
- |
Total Dissolved Solids |
0% |
0% |
- |
- |
Fecal Coliform |
(see note) |
-- |
(see note) |
(see note) |
Lead |
100% |
100% |
- |
- |
Mercury |
0% |
0% |
- |
- |
Nickel |
100% |
100% |
- |
- |
Nitrite |
100% |
79% |
- |
- |
pH |
100% |
100% |
- |
- |
Total Phosphorus (guidance value) |
Not in compliance (summer average guidance
value) |
- |
- |
- |
Zinc |
100% |
100% |
- |
- |
Nearshore
Class B stations in the vicinity of:
Bloody Brook, Nearshore
Class C stations in the vicinity of:
Ley Creek, Metro, Onondaga Creek, Harbor Brook and Ninemile
Creek. |
||||
Notes: Ammonia-N
compliance represented as average of discrete depth percent compliance. Dissolved
Oxygen compliance based on water quality buoy data at 2m and 12m depths. Fecal
Coliform bacteria data are assessed as monthly geometric means (GM) during
the period of Metro disinfection (April –Oct). Fecal Coliform concentrations
(monthly geometric means) did not exceed the water quality standard at
offshore locations [upper mixed layer (0-6 m)] or at nearshore Class B waters
locations. For nearshore locations in
Class C waters, GM concentrations were below the water quality standard,
except at two locations (standard exceeded 86% and 43% of the time, see
Figure 5-6). Mercury
samples collected at 3m and 18m depths, 3 dates, ultra low-level measurement. Total
Phosphorus compliance based on upper waters samples (0, 1 and 3 m depths)
averaged June 1 to Sept 30 |
The productivity of
When algal biomass settles to the lower, unlighted areas of a productive
lake, its decay robs the lower waters of dissolved oxygen, making them
uninhabitable by fish or other oxygen-requiring organisms. Under these anaerobic or oxygen-free
environments, undesirable compounds such as ammonia and soluble phosphorus may
be released from the sediments.
Monitoring the trophic status of
Since
the productivity of
One of the undesirable attributes of eutrophic lakes is
their green-tinged water and turbidity, diminishing their suitability for water
supply and recreational uses. Abundant phytoplankton
are a primary factor affecting turbidity; in most lakes there is a strong
correlation between phosphorus, chlorophyll-a (the primary photosynthetic
pigment in algal cells) and water clarity.
The EPA and NYSDEC are developing nutrient criteria for lakes to protect
water supply and recreational use, as well as deriving numerical limits on
response variables such as chlorophyll-a.
In the absence of state or federal criteria, the AMP has used
site-specific criteria of 15 µg/L (minor bloom) and 30 µg/L (major bloom) to
screen algal bloom thresholds for
In
Figure 5‑1. Chlorophyll-a concentration, January to December,
1998-2010.
There
is also a strong correlation between the TP present in the lake during the
spring, prior to the development of thermal stratification and the algal abundance in the summer
months. In
In
lakes where phytoplankton abundance is limited by phosphorus, the two trophic
state parameters are highly correlated. Data from regional lakes (Figure 5-2) illustrate this relationship. Data for the
Figure
5‑2. Summer (June- August) average TP and
chlorophyll-a concentrations in
The top panel shows
Another—and
more direct—indicator of turbidity of the water is the Secchi disk
transparency. A Secchi disk is a 25 cm
diameter disk with alternating black and white quadrants. It can be lowered into the lake, and the
depth at which it can no longer be seen from the surface or from the deck of a
boat, is known as the Secchi disk transparency.
Greater depth indicates clearer and less productive waters. Highly productive waters may have Secchi disk
measurements of less than one meter. Water clarity data are influenced by both
bottom-up (nutrient levels) and top-down (food web) effects; the presence and
abundance of grazing organisms has a major impact on the algal community.
To meet swimming safety guidance, Secchi disk transparency
greater than 1.2 m is required at designated beaches. There is no NYS standard or guidance value
for Secchi disk transparency of off-shore waters; most lake monitoring programs
in the state monitor Secchi disk transparency at a mid-lake station overlying
the deepest water, comparable to Onondaga Lake South Deep station. The Citizens Statewide Lake Assessment
Program (CSLAP),a joint effort of NYSDEC and the NYS Federation of Lake
Associations, considers summer average Secchi disk transparency greater than 2
m as indicative of mesotrophic conditions (Kishbaugh 2009). The water clarity of Onondaga Lake was
slightly lower during the very wet summer of 2010, averaging 1.9 m and ranging
from 0.8 m to 2.9 m over the June – September interval (Figure 5.3). Results in 2010
were comparable to the 2007 water
clarity conditions.
Figure 5‑3. Secchi Disk transparency, Onondaga Lake
South Deep, 2010.
In addition to Secchi disk
transparency, the AMP includes measurements of light extinction using a LiCor
instrument and data logger. These measurements correlate
with Secchi disk transparency measurements.
The wet summer resulted in increased
loading of suspended sediments. The mud boils on upper Onondaga Creek may have
contributed to the diminished water clarity of the lake in 2010, and therefore
to the slight divergence in TSI values calculated for chlorophyll and water
clarity. According to USGS scientist William Kappel, a surge of mudboil
activity began in early March 2010 (personal communication May 2011). This outbreak caused direct discharge of
mudboil sediments to the creek, returning turbidity to early 1990 levels. Sediment loading to Onondaga Creek increased
from approximately 0.1 metric tons per day between October 2009 and February
2010 to several metric tons per day later in 2010. On several occasions, the
mud boils resulted in a sediment load to Onondaga Creek between 10 and 40
metric tons/day. Overall, Mr. Kappel
estimated the average sediment load during the 2010 water year from mud boils
at approximately 1 metric ton/day. However, during the critical March-September
period, the mud boils likely contributed approximately six MT/day of
fine-grained sediment to Onondaga Creek (William Kappel, USGS personal
communication May 2011).
In addition to
the increased suspended solids input from the watershed in 2010, food web
effects also contributed to the loss of water clarity. The resurgence of a
strong year-class of the alewife has dramatically affected the larger
zooplankton species; these efficient grazers of phytoplankton are now
essentially absent from the community,
resulting in increased algal biomass and reduced light penetration in the water
column. This topic is discussed further in Section 6.
Figure 5‑4. TSI conditions based on summer (June 1 –
September 30) data, 1998-2010.
A lake’s dissolved oxygen (DO) content is a critical factor
for aquatic life. As discussed in prior sections of this report, a restoration
goal for
Figure 5‑5. First
date of measured anoxic conditions at 15m depth,
Prior to the engineering
improvements at Metro to bring about year-round nitrification of wastewater,
Table 5‑2. Percent of Ammonia
Measurements in Compliance with Ambient Water Quality Standards, Onondaga Lake,
1998-2010.
Depth (m) |
Percent
measurements in compliance, NYS standard* |
||||||||||||
1998 |
1999 |
2000 |
2001 |
2002 |
2003 |
2004 |
2005 |
2006 |
2007 |
2008 |
2009 |
2010 |
|
0 |
64 |
62 |
86 |
95 |
68 |
96 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
3 |
45 |
67 |
90 |
90 |
68 |
96 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
6 |
50 |
86 |
90 |
95 |
73 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
9 |
41 |
76 |
90 |
95 |
73 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
12 |
18 |
52 |
90 |
81 |
50 |
80 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
15 |
23 |
52 |
57 |
52 |
41 |
56 |
80 |
100 |
100 |
100 |
100 |
100 |
100 |
18 |
23 |
48 |
52 |
38 |
32 |
48 |
75 |
95 |
95 |
100 |
100 |
100 |
100 |
*6 NYCRR §703.5 Water quality standards for taste-, color-
and odor-producing, toxic and other deleterious substances (http://www.dec.ny.gov/regs/4590.html#16130) |
The suitability of
The applicable NYS
ambient water quality standard for fecal coliform bacteria in surface water, as
set forth in 6NYCRR Part 703.4, is as follows:
Fecal coliforms (number
per 100 ml).
Classes |
Standard |
A, B, C, D, SB, SC |
The monthly geometric mean, from a minimum of five examinations,
shall not exceed 200 |
This standard is used
to assess bacterial contamination at nearshore locations (Figure 5-6) as well as at the open water sites
North Deep and South Deep (refer to Figure 1-2). Bacteria levels in portions of the lake typically increase
following significant rainfall, and concentrations often vary by
orders of magnitude due to the event-driven nature of the sources. Consequently, geometric means are best suited
for examining spatial and temporal trends.
The NY state standard for fecal
coliform bacteria is assessed by taking frequent samples, a minimum of five per
month, and calculating the geometric mean of the results. The ambient water quality standard for fecal coliform
bacteria, designed to protect human health during water contact recreation, is
set at 200 cfu (colony-forming units) per 100 ml of lake water. The standard applies during the period of
Metro disinfection, which is April 1st – October 15th.
In 2010, bacteria
counts at the monitoring stations were less than the fecal coliform bacteria
standard at all but two nearshore monitoring locations within the Class C
segment at the lake’s southeastern shoreline (Figure
5-6). In addition, bacterial counts at the two
offshore monitoring locations, North Deep and South Deep, were below the AWQS
for fecal coliform bacteria during the 2010 assessment period.
Figure 5‑6. Fecal
coliform bacteria results,
Note: Compliance is calculated for each location by
comparing the monthly geometric mean of a minimum of five samples with the AWQS
(200 cfu/100 mL). For October, the geometric mean includes three samples, as
Metro disinfection ends October 15th in accordance with the
facility’s SPDES permit.
Water
clarity is measured at the same network of nearshore stations. While there is no NYSDEC standard for water
clarity, the NYS Department of Health (DOH) has a swimming safety guidance
value for designated bathing beaches of 4 ft. (1.2 m). The 2010 results demonstrate that the DOH
swimming safety guidance value was
met throughout the summer recreational period (June 1st
- Sept 30th) at all but two
monitoring locations. These two
nearshore areas - near the mouth of Onondaga Creek – met the swimming safety
guidance value 90% and 5% of the time, respectively. The mud boils on upper Onondaga Creek may
have contributed to the diminished water clarity of these two nearshore
stations (see Section 5.3.4 for discussion
of mudboils in 2010).
Onondaga County WEP has monitored nearshore water quality conditions as part of the AMP since 2000. The monitoring program includes both routine sampling and sampling following storm events. Dr. William Walker has completed a trend analysis of the water clarity and bacteria data through 2010. The analysis is included in the library. The significant findings of his analysis are summarized in this section.
Storm-driven discharges from
urban and agricultural areas can trigger significant increases in turbidity and
bacteria levels due to wash-off of pollutants from land surfaces and overflow
of combined sewers. Evaluating long-term
trends can be difficult due to high variability of these data and their
dependence on antecedent hydrologic conditions.
Dr. William Walker segregated the monitoring data into “wet” and “dry”
weather events, using a 3-day antecedent rainfall of less than 0.5 inches of
rainfall, as measured at
·
North end cluster, stations adjacent to: Ninemile Creek,
· South end cluster, stations adjacent to: Ley Creek, Mid-South (near Metro outfall), and Harbor Brook.
In addition, Dr. Walker examined the trends from the South Deep station, to provide a basis for comparison to the nearshore stations.
Water clarity at the nearshore lake stations has increased over the AMP monitoring period. This increase is both statistically significant, and ecologically important as evident from the expansion of macrophyte growth into deeper waters and the cascading benefits on aquatic habitat and sediment stabilization. Turbidity is a far more robust indicator parameter for the statistical trend analysis, because many of the Secchi disk transparency data were recorded as greater than 1.2 m. This result indicates compliance with the NYS Department of Health swimming safety guidance value, but diminishes the power of the statistical analysis for trend detection. The only station not exhibiting a statistically significant decrease in turbidity was the Waste Beds, which was included in the AMP in 2007 and has a shorter period of record.
Fecal coliform levels are clearly higher during wet weather
as compared to dry weather, especially at the southern nearshore stations
(adjacent to Ley Creek, Onondaga Creek and Harbor Brook). Over time, there has been a decreasing trend
in wet-weather bacterial abundance at the southern nearshore stations, as well
as at the northern station adjacent to Bloody Brook. These patterns are generally consistent with
reductions in storm-related bacteria sources (runoff, CSOs, Metro Bypass). In contrast, the dry weather data indicate
increasing trends over time at southern nearshore stations near Harbor Brook
and the Metro outfall. This increasing
trend is consistent with the increasing trend in fecal coliform bacteria
measured in Harbor Brook at the
Between 2003 and 2010, monthly geometric means exceeded the regulatory limit of 200 cfu/100 mL in three of 60 summer months in the nearshore station close to Metro and at the mouth of Onondaga Creek. For all other monitoring locations in the lake, summer monthly geometric means never exceeded the regulatory limit over this eight-year period.
The improvements to the Metro treatment
plant have resulted in significant reductions in ammonia and phosphorus loads
to Onondaga Lake, and an associated steep decline in the concentrations of
these nutrients in the lake water (Table 5-3; Figure
5-7; refer also to Figure EX-1 and Figure
EX-3). Ammonia N met
the AWQS at all depths throughout 2010. Productivity has declined, algal
biomass is reduced, and the lake has exhibited mesotrophic conditions since
2007.
Table 5‑3. Summary
of trends in lake concentrations, 2001-2010.
|
|
|
|
|
Nearshore** |
||||
Variable |
|
Upper Waters |
Lower Waters |
Upper Waters |
Lower Waters |
12
m |
2
m |
North Sites |
South Sites |
Clarity |
Secchi disk transparency |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
|
Turbidity |
○ |
- |
- |
- |
- |
- |
↓ |
↓ |
Bacteria |
Fecal coliforms |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
○ |
|
E. Coli |
○ |
- |
- |
- |
- |
- |
↓ |
○ |
Nitrogen |
Ammonia-Nitrogen as N (NH3-N) |
↓ |
↓ |
↓ |
↓ |
↓ |
↓ |
- |
- |
|
Nitrite as N (NO2-N) |
↓ |
○ |
↓ |
○ |
↓ |
↓ |
- |
- |
|
Nitrate as N (NO3-N) |
↑ |
↑ |
↑ |
↑ |
↑ |
↑ |
- |
- |
|
Organic Nitrogen as N |
↓ |
↓ |
↓ |
○ |
↓ |
↓ |
- |
- |
|
Total Kjeldahl Nitrogen as N (TKN) |
↓ |
↓ |
↓ |
↓ |
↓ |
↓ |
- |
- |
Phosphorus |
Total Phosphorus (TP) |
↓ |
↓ |
↓ |
↓ |
↓ |
↓ |
- |
- |
|
Soluble Reactive Phosphorus (SRP) |
↓ |
↓ |
↓ |
↓ |
↓ |
↓ |
- |
- |
Solids |
Total solids (TS) |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
Total suspended solids (TSS) |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
Total dissolved solids (TDS) |
○ |
○ |
○ |
○ |
↓ |
○ |
- |
- |
|
Volatile suspended solids (VSS) |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
Chlorophyll |
Chlorophyll-α |
↓ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
Phaeophytin-α |
○ |
○ |
○ |
○ |
↓ |
○ |
- |
- |
Carbon |
Total organic carbon (TOC) |
↓ |
↓ |
↓ |
↓ |
↓ |
↓ |
- |
- |
|
Total organic carbon, filtered (TOC-F) |
↓ |
↓ |
↓ |
↓ |
↓ |
↓ |
- |
- |
|
Total inorganic carbon (TIC) |
○ |
↓ |
○ |
○ |
○ |
○ |
- |
- |
Other |
Alkalinity as CaCO3 |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
Bio. oxygen demand 5-day (BOD5)* |
- |
- |
- |
- |
- |
- |
- |
- |
|
Calcium (Ca) |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
Chloride (Cl) |
○ |
○ |
○ |
○ |
↓ |
○ |
- |
- |
|
Conductivity |
○ |
○ |
○ |
○ |
○ |
↓ |
- |
- |
|
Dissolved Oxygen (DO)*** |
○ |
↑ |
○ |
↑ |
↑ |
○ |
- |
- |
|
Hardness |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
Magnesium (Mg) |
↓ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
Sodium (Na) |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
pH |
○ |
○ |
○ |
○ |
↑ |
○ |
- |
- |
|
Silica (SiO2) |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
|
Sulfate (SO4) |
↓ |
↓ |
○ |
○ |
↓ |
↓ |
- |
- |
|
Temperature |
○ |
○ |
○ |
○ |
○ |
○ |
- |
- |
Notes: Significance
level, two-tailed, seasonal ↓ indicates decreasing trend (p > 0.1) ↑ indicates increasing trend (p < 0.1) ○ circle symbol indicates no trend (p = 0.1) - Dash indicates parameter was not measured
at this location, or trend analysis was not conducted. * BOD5
(Biochemical Oxygen Demand (5-day)) trend analysis results are not accurate
because of the preponderance of data less than the MRL (PQL). **Nearshore analyses conducted by
Bill Walker on data from 1999-2010 ( *** Although |
Figure 5‑7. TP
loading (water year), all external sources and summer TP concentration
The relationship between Metro TP
load and lake response is illustrated in Figure
5-7.
The loading calculations presented in this graph are based on water year
(October 1- Sept 30). While a 12-month loading estimate is important
to capture all the seasons, correlating summer water quality with the corresponding
calendar year loads is not a reasonable
approach, because
October-December comes after June-September. The water year (October-September)
interval is a rational approach, especially
considering the lake’s short water residence time, and has been widely used in other
lake models. For additional
discussion of the empirical mass-balance framework for
The annual loading is a less
robust measure of summer average TP in the upper waters, due to the inclusion
of the fall months. As illustrated in Figure 5-8(A),
the TP input from Metro accounts for approximately 74% of the annual variation
in the TP concentrations of the lake’s upper waters. When watershed load is
included (this source is more variable), the correlation is weaker, as
displayed in Figure 5-8(B).
Figure 5‑8. Relationship of Metro TP loading and lake summer TP (panel A-linear regression)
and all sources TP
loading and lake summer TP (panel B-linear regression).
Effluent total N has remained
relatively constant as the total P has declined after 2005, resulting in a
significant increase in the ratio of N:P in the lake’s upper waters (Figure 5-9).
The relative availability of these two nutrients affects the species
composition and abundance of the phytoplankton community. Algal cells require
both N and P for growth, and require these nutrients in a ratio that
approximates their presence in the cellular protoplasm (the stoichiometric ratio). The
stoichiometric ratio for algal cells is estimated as 16N:1P.
Nitrogen can become limiting to
algal productivity when the available N:P supply ratio declines below a
critical value, variously cited as in the range of 29:1 or lower (the red line
on Figure 5-8 is drawn at 16, with a band around it reflecting the range of
values cited in the literature). When
the ratio of total N to total P in the water column declines to low values, P
is present in abundance relative to the stoichiometric needs of the
algal cells, and N may become limiting (Hall et al. 2005). Once N is limiting, several species of
cyanobacteria, which can utilize atmospheric nitrogen, have a competitive
advantage over other algal groups. In
productive lakes, this leads to blooms of cyanobacteria and associated water
quality problems. Cyanobacteria, once common, have comprised only a small
fraction of the phytoplankton community since 2006.
Figure 5‑9.
The
ratio is concentration-based, where the ratio for each sample date was
calculated, then the ratios were averaged to represent summer for each
year. The summer average represents the
period June 1 to September 30. Total N
was calculated as the sum of Total Kjeldahl Nitrogen (TKN), nitrite-N and
nitrate-N concentrations; TP was reported by the laboratory. Nitrite-N and nitrate-N samples were
collected as composites of the upper mixed layer (UML); TKN and TP were
collected at discrete depths, and the results were averaged for 0m and 3m
depths to represent upper waters.
The transformation in the quality of Metro
effluent has effected a fundamental change in the lake ecosystem. A reduced phosphorus supply has resulted in
lower algal biomass, since phosphorus is now firmly established as the limiting
nutrient for algal growth in
The AMP results document improved DO in the lake’s upper and lower waters. The water quality monitoring buoy deployed at South Deep provides frequent measurements of the DO at 2 m and 12 m depths. Despite the year-to year variability in the onset of thermal stratification, the diminished mass of algae reaching the sediment surface has contributed to a later onset of anoxia and improved DO in the lake’s lower waters.
The oxidation of ammonia to nitrate in Metro’s
biological treatment system has resulted in a statistically significant
increase in nitrate concentrations in the lake’s upper
and lower waters. The increased nitrogen concentrations are also
a consequence of the lower phosphorus loading.
As phosphorus and algal productivity have declined, there is diminished
uptake of all forms of nitrogen from the water column.
The presence of nitrate in the lower waters has
affected the redox status of the lower waters, and modified the dynamics of
sediment phosphorus release. As oxygen
is depleted from the deep waters (Figure 5-10A),
nitrate serves as an alternate electron acceptor for the microorganisms
actively decomposing organic material settling out of the photic zone. Nitrate in the deep waters (Figure 5-10B) delays the reduction of iron and
manganese, and phosphorus bound to these minerals remains trapped in the lake
sediments.
Figure 5‑10. LWL
concentrations of SRP, NO3-N and DO, 2006-2010.
Comparing the 2010
results to those of previous years highlights the effect the increasing nitrate
levels have had on the redox status of the lake’s hypolimnion, as reflected in
the diminished accumulation of SRP in the lower waters during the summer period
of thermal stratification (Figure 5-10B).
Once iron and manganese are reduced, phosphorus is released to the
overlying waters and the SRP concentrations in the hypolimnion increase. If the phosphorus released to the upper
waters includes more than that represented by decomposition of algae from the
current year, it may be considered as an internal load (recycle). During
2010, the redox status of the lake’s lower waters (15 m and deeper) ranged
from a low value of 50 mv on 8/10/11 to values greater than 300 mv (late June
and again in November).
An estimate
of the mass of phosphorus released from the lake sediments
during the stratified period each year indicates that there is a great deal of
variability; some change may be a result of improving redox status of the
hypolimnion. However, variations in
algal production and the duration of stratification also affect the magnitude
of the internal phosphorus recycling.
A summary of the 2010
results of all parameters measured in
This section of the Annual Report reviews the extensive AMP data describing the phytoplankton, macrophyte, zooplankton, macroinvertebrates, dreissenid mussel and fish communities that comprise the Onondaga Lake food web.
As phosphorus concentrations in
Since the late 1990s, the biomass of phytoplankton, which
includes algae and cyanobacteria, in
Figure 6‑1. Reduction in the
The composition of the phytoplankton community has changed from one dominated by undesirable cyanobacteria (blue-greens) and pyrrhophytes (dinoflagellates) to one dominated by more desirable diatoms and chlorophytes (green algae) (Figure 6-2). Moreover, among the cyanobacteria that appeared briefly in the lake in the fall of 2010, the large nitrogen-fixing and often toxic colonial cyanobacteria (Microcystis, Anabaena, and Oscillatoria) were essentially absent.
The improved water clarity, allowing more light to penetrate to the bottom in inshore areas, has led to a trend of increasing colonization by macrophytes, and the littoral zone is covered with plants (refer to Figure EX-10). The diversity of this aquatic plant community has also increased dramatically from a low of 5 or 6 species in the early 1990s to 23 species in 2010 (refer to Figure EX-11).
Although phytoplankton abundance in 2010 was slightly higher than measured in 2009, the average algal biomass for April-October remained well below that expected for a meso-eutrophic lake (3-5 mg/l, Wetzel 2001) and is similar to that of 2007, at 1.3 mg/l (refer to Figure 6-1). Peak algal biomass did not exceed 3.0 mg/l in 2010, confirming the lake’s mesotrophic status. Over the last decade, phytoplankton biomass has declined significantly, and the years from 2007 to 2010 were the four lowest years on record. This decline is likely due both to the improved removal of phosphorus from the Metro effluent and to increased grazing by dreissenid mussels. Large zooplankton were extremely rare in 2010 and algal biomass increased marginally compared to 2008 and 2009. Interestingly, quagga and zebra mussels also declined in 2010 compared to 2009.
Diatoms (Bacillariophyta) continued to dominate the
phytoplankton community, and showed three peaks, an early spring peak, a
mid-spring peak, and a fall peak (Figure 6-2 and
Figure 6-3).
In 2009, an exotic diatom species not previously identified from
Figure 6‑2. Proportional biomass of phytoplankton
divisions, 2010.
Figure 6‑3. Phytoplankton community structure and biomass, 2010.
Cyanobacteria and dinoflagellates, which dominated the phytoplankton community in Onondaga Lake until 2001, have now nearly disappeared from the lake, and nuisance blooms of Aphanizomenon (A. gracile and A. flos-aquae), which were typical of summers before 2000, no longer occur. The species of cyanobacteria remaining in the lake are smaller in size, and peak cyanobacteria abundance reached only 0.05 mg/l in 2010, just slightly higher than in 2009 (0.03 mg/l).
Along with phytoplankton, aquatic macrophytes (plants) are also an important component of lake ecology; the rooted plants and algae have major effects on productivity and biogeochemical cycles. Macrophytes produce food for other organisms and provide habitat for aquatic invertebrates, fish, and wildlife, and help to stabilize sediments. As part of the ACJ, the AMP included extensive sampling of the lake’s macrophyte community in 2000, 2005, and 2010 to complete a species list and document changes in biomass. Aerial photographs of the littoral zone are collected annually (when water clarity allows) to determine plant distribution.
The macrophyte community continued its expansion within the lake’s littoral zone in 2010. Based on annual aerial photographs, coverage has expanded from 85 acres in 2000 to 409 acres in 2010 (Figure 6-4). The aerial photos do not enable species identification, only percent cover.
Figure 6‑4. Macrophyte distribution, 2000 – 2010.
The detailed survey completed in 2010 documented 23 unique
macrophyte species in the lake, compared with 17 species in 2005 and 10 species
in 2000. This increase in species
richness is due nearly entirely to establishment of native species; only two of
the 13 new species documented since 2000 are non-native. The most abundant species were submersed
macrophytes (Table 6-1). Seven of the species documented in the 2010
survey had not been observed in the lake previously. These new species were relatively rare in the
lake, each accounting for less than 4% of the total plant coverage and biomass
in the lake. Straight-leaf pondweed,
designated as endangered within
Table 6‑1. Species list of aquatic macrophytes observed in in current (2010) survey, past studies, and documented historical observations. |
||||||||
Species |
2010 |
2005 |
2000 |
1995 |
1993 |
1992 |
1991 |
Historical |
Ceratophyllum demersum |
X |
X |
X |
X |
X |
X |
X |
1 |
Chara
sp. |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
3 |
Chara
vulgaris |
X |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
Elodea canadensis |
X |
X |
X |
-- |
-- |
-- |
-- |
-- |
Fontinalis sp. |
X |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
Lemna
minor |
X |
X |
-- |
-- |
xx |
-- |
-- |
-- |
Lemna
trisulca |
X |
X |
-- |
-- |
-- |
-- |
-- |
-- |
Myriophyllum spicatum |
X |
X |
X |
X |
X |
X |
X |
-- |
Najas
flexilis |
X |
X |
-- |
-- |
-- |
-- |
-- |
-- |
Najas
guadalupensis |
X |
X |
-- |
-- |
-- |
-- |
-- |
-- |
Najas marina |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
1,2,4 |
Nitella
flexilis |
X |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
Nitella
sp. |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
5 |
Nitellopsis obtusa |
X |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
Polygonum amphibium |
X |
-- |
-- |
-- |
-- |
-- |
-- |
3 |
Potamogeton crispus |
X |
X |
X |
X |
X |
X |
X |
2 |
Potamogeton diversifolius |
-- |
-- |
-- |
-- |
xx |
-- |
-- |
-- |
Potamogeton pusillus |
X |
X |
X |
-- |
-- |
-- |
-- |
-- |
Potamogeton strictifolius* |
X |
X |
-- |
-- |
-- |
-- |
-- |
-- |
Ranunculus longirostris |
X |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
Ranunculus sp. |
-- |
-- |
X |
-- |
-- |
-- |
-- |
-- |
Ruppia
maritima |
X |
X |
-- |
-- |
-- |
-- |
-- |
-- |
Sagittaria latifolia |
-- |
X |
X |
-- |
-- |
-- |
-- |
-- |
Sparganium sp. |
-- |
-- |
-- |
-- |
xx |
-- |
-- |
-- |
Spirodela polyrhiza |
X |
X |
-- |
-- |
-- |
-- |
-- |
-- |
Stuckenia pectinata |
X |
X |
X |
X |
X |
X |
X |
1,2,3 |
Stuckenia vaginata |
X |
-- |
-- |
-- |
-- |
-- |
-- |
-- |
Trapa
natans |
X |
X |
-- |
-- |
-- |
-- |
-- |
-- |
Vallisneria |
X |
X |
X |
-- |
-- |
-- |
-- |
-- |
Zannichellia palustris |
-- |
-- |
-- |
-- |
xx |
-- |
-- |
5 |
Zosterella dubia |
X |
X |
X |
X |
X |
X |
X |
1,2,3,4 |
Total Number |
23 |
17 |
10 |
6 |
10 |
6 |
5 |
9 |
Notes: * indicates endangered species;
"X" indicates presence; "--" indicates absence;
"xx" only a few plants found behind experimental wave breaks. Historical presence indicated by note
number. Sources for surveys by years: Historical
Sources: 2010 Survey (OCDWEP 2011) 1.
Paine (1865) 2005 Survey (OCDWEP 2006) 2.
Bye and Oettinger (1969) 2000
Survey ( OCDWEP 2001) 3.
1995 Survey (Arrigo 1995) 4.
Goodrich (1912) 1993
Survey (Madsen et al. 1996b) 5. Dean
and Eggleston (1984) 1992
Survey (Exponent 1998 and Madsen et al. 1996b) 1991 Survey (Madsen et al. 1996a) |
The zooplankton community is a pivotal component of the lake
ecosystem; these grazing aquatic animals affect the abundance and species
composition of the phytoplankton community, and are, in turn, affected by the
fish community. The size structure and
abundance of the
The size structure of the zooplankton community, i.e., the relative abundance of small and large species, is a consequence of the grazing pressure exerted on zooplankton by fish. The temporal changes in the zooplankton community are linked to changes in predation by the dominant fish planktivore in the lake, the alewife (Alosa pseudoharengus) (Wang et al. 2010). In general, the alewife tend to feed on larger zooplankton species leaving smaller zooplankton alone. When alewife populations are high, the population of larger zooplankton species declines. In the absence of alewife predation, the population of larger zooplankton species increases, as illustrated in Figure EX-13. This in turn affects the phytoplankton community, as larger zooplankton are far more efficient grazers than the smaller zooplankton; the presence of larger organisms results in less algae and clearer waters (refer to Figure EX-14).
The average biomass of all zooplankton in the lake (as measured in dry weight) was lower during April-October 2010 (143 µg/l) than it was for the same period in 2009 (236 µg/l). The peak zooplankton biomass, evident in late-June 2010, was 884 µg/l. During this period of peak abundance, the zooplankton community was dominated by taxa in the family Bosminidae, which are small crustacean species (Figure 6-5). The low biomass of Daphnia – larger zooplankton - in the years between 2003 and 2007 and then again in 2010 (Figure 6-6) is attributed to the presence of abundant alewife during these time periods.
Figure 6‑5. Average biomass of zooplankton, proportion of major groups.
Figure 6‑6. Biomass of various Daphnia species in
The data from
Figure 6‑7. Average size of all crustacean zooplankton in
Figure 6‑8. Average crustacean zooplankton length (mm), 2009 and
2010.
Increased alewife abundance had an important cascading
effect on lower levels of the food web.
At the level of the zooplankton, alewife feeding selectively on larger
zooplankton leads to lower biomass and smaller average size of the crustacean
zooplankton (refer to Figure EX-13). Smaller zooplankton are less efficient than
larger ones in harvesting phytoplankton, and phytoplankton abundance increases
as a result. More abundant phytoplankton
results in increased primary production and decreased water clarity, typically
measured as Secchi disk transparency. The relationship between zooplankton size
and water clarity was illustrated in Figure EX-14. These top-down effects are often referred to
as a “trophic cascade”, with alternating increases and decreases between
adjacent levels of the food web. The
strong year-class of alewife in 2009 precipitated such a trophic cascade with noticeably
reduced Secchi disk transparency measurements and increased chlorophyll-a
and total P levels in summer 2010. Note
that total P loading did not increase from 2009 to 2010 although a wet summer
led to higher P loading from the watershed (refer to Figure 5-6).
Zebra mussels (Dreissena
polymorpha) were introduced into the Great Lakes from
These benthic mussels are filter feeders, and, as such,
exercise a top-down effect on phytoplankton abundance similar to that of the
zooplankton. The high mussel biomass
since 2007 suggest continued high grazing pressure from these mussels on
phytoplankton. However, the littoral
zone is relatively small in
Figure 6‑9. Dreissenid mussel average density and
biomass with standard deviation, 2002-2010.
(Note: where average quagga and
zebra mussel biomass by zone were reported separately (2009 and 2010), the
biomasses of each species in each zone were averaged to obtain total average
mussel biomass by zone. Average zone
biomasses were then averaged, and standard deviation calculated, for the lake
biomass as presented in this graphic.)
Figure 6‑10. Relative abundance of dreissenid mussels, 2002-2010.
In
addition to the biennial tributary macroinvertebrate monitoring, Onondaga County
WEP samples and analyzes the macroinvertebrate community of the lake’s littoral
zone every five years. Samples are
collected at five reference locations around the littoral zone. Macroinvertebrate organisms are separated
from the lake sediments, identified, and enumerated. These data are used to calculate NYSDEC
standard benthic community indices, indicating the existence and severity of
impairment. In addition, chironomids in
the littoral samples were examined for deformities. The complete
report and data files from the 2010 investigation, including detailed
comparisons with results from 2000 and 2005, are included in the Library (reference
L08.7). Highlights of the report are
included in this section of the annual report.
The
macroinvertebrate community of the littoral zone has shown considerable
improvement since 2000, as displayed in Figure 6-11. The designation of low and high energy
regions refers to wave energy, and is a result of
the lake’s orientation and prevailing winds. The lake’s littoral zone is
affected by many factors including substrate texture and organic matter. The improvement in the
macroinvertebrate community metrics is most pronounced at those stations (Site
3 – Metro, and Site 4 –Ley Creek) that were in the poorest condition in
2000. Although the community at Site 3
was still categorized as severely
impacted in 2010, it has improved steadily since 2000 and is approaching a moderately impacted condition. Three (Sites 2, 4, and 5) of the five sites
are now categorized as slightly impacted. Changes in macroinvertebrate community
composition are evident throughout much of the lake in the form of higher
species richness and diversity, which have resulted in improved scores for
Biological Assessment Profile (BAP), Hilsenhoff Biotic Index (HBI), and Percent
Model Affinity (PMA). These changes are
likely a response to improvements in water quality, decreased organic loading,
improved dissolved oxygen conditions in littoral sediments, and increases in
macrophyte abundance and coverage.
Despite the noted improvements, the littoral
macroinvertebrate community of
The improving trends in littoral
macroinvertebrate community metrics since 2000 should continue as the lake
responds to improvements in wastewater collection and treatment, both at Metro
and the combined sewer overflows, and other remediation efforts occurring
within the lake and surrounding watershed.
The ongoing expansion and diversification of the aquatic macrophyte
community throughout the lake’s littoral zone will also contribute to changes
and likely improvements to the littoral macroinvertebrate community.
Table 6‑2. Mean index value and
corresponding NYSDEC water quality assessment score from petite Ponar samples
(with dreissenid mussels included in the sample) for sites in |
||||||||||
|
Site 1 |
Site 2 |
Site 3 |
Site 4 |
Site 5 |
|||||
|
|
Wastebeds |
Metro |
Ley Creek |
Hiawatha Point |
|||||
Benthic Community Indices |
Index |
NYSDEC |
Index |
NYSDEC |
Index |
NYSDEC |
Index |
NYSDEC |
Index |
NYSDEC |
Richness |
13.6 |
4.41 |
11.7 |
3.48 |
9.94 |
2.44 |
12.6 |
3.91 |
14.9 |
5.22 |
Diversity |
2.45 |
4.56 |
2.65 |
5.78 |
2.26 |
3.81 |
2.86 |
6.65 |
3.02 |
7.29 |
Dominance-3 |
0.722 |
5.40 |
0.702 |
5.77 |
0.805 |
4.08 |
0.641 |
6.82 |
0.608 |
7.37 |
PMA |
45.0 |
3.04 |
59.1 |
5.82 |
28.4 |
0.433 |
59.6 |
5.92 |
57.4 |
5.49 |
HBI |
8.12 |
4.71 |
7.27 |
6.82 |
9.70 |
0.744 |
7.52 |
6.20 |
7.80 |
5.51 |
NYSDEC Site Mean Water Quality Value |
4.4 |
5.5 |
2.3 |
5.9 |
6.2 |
|||||
Level of Impact |
Moderate |
Slight |
Severe |
Slight |
Slight |
|||||
Notes: NYSDEC WQ Scale Mean refers to the water quality score resulting from a
calculation based on the benthic community index. The calculations are found in the NYSDEC report
“Standard Operating Procedure:
Biological Monitoring of Surface Waters in Indices: Richness = a measure of
the number of species present; Diversity = a measure of species diversity;
Dominance-3 = combined percent contribution of three most numerous species;
PMA = Percent Model Affinity, a measure of similarity to a model non-impacted
community; HBI = Hilsenhoff Biotic Index, a measure of community tolerance to
pollution. |
Figure 6‑11. Spatial depiction of littoral macroinvertebrate
community data.
Changes in the fish community of
Table 6‑3. Fish species identified in Onondaga Lake,
2000-2010. |
|||||
Abundant Species |
Common Species |
Uncommon Species |
|||
Alewife Banded killifish Bluegill Brown bullhead Carp Gizzard shad Golden shiner |
Largemouth bass Pumpkinseed Smallmouth bass Walleye White perch White sucker Yellow perch |
Black crappie Bluntnose minnow Bowfin Brook silverside Brook stickleback Brown trout Channel catfish Emerald shiner |
Fathead minnow Freshwater drum Longnose gar Logperch Northern
pike Rock bass Tessellated darter Shorthead redhorse |
Black bullhead Chain pickerel Goldfish Greater redhorse Green sunfish Johnny darter Longnose dace Northern hogsucker |
Quillback Rainbow smelt Rainbow trout Round goby Rudd Silver redhorse Spotfin shiner Tiger muskie Trout perch White bass Yellow bullhead |
Several important metrics of the
fish community are based on measured diversity and richness of the adult fish community,
both littoral (near-shore) and pelagic (open water). Richness is a count of the number of species
within a community, while diversity considers both the number of species
present and their relative abundance. In
The diversity
of fish communities fluctuates in response to changes in seasonal and
environmental variables, and inter-species competition. In
The AMP employs several methods to assess fish reproduction, including nesting surveys, sampling of larval fish, and sampling of young of year fish. Evaluation of the young fish provides information on the overall health of the fish community within the lake and success of reproduction from year to year. Factors other than water quality, including water temperature during and after spawning, water levels, and trophic dynamics, can affect reproductive success and need to be considered as well.
The centrarchid species in the lake (largemouth and smallmouth bass, pumpkinseed and bluegill sunfish, rock bass) and bullhead construct nests in the littoral zone. Each year, the AMP team conducts nesting surveys to estimate the number and spatial distribution of the nests. In 2010, 2,050 nests were observed (Figure 6-12), with a slightly skewed distribution between the north and south basins, (60% and 39%, respectively).
Figure 6‑12. Nesting survey
map and comparison of north vs. south-2010.
This represents a slightly less even distribution than in the past two years, although not as skewed as earlier years, for example, in 2007, 84% of the nests were located in the northern basin. Approximately one third of the nests supported pumpkinseed sunfish.
During sampling in 2010, larval
stages of alewife, bluegill, and pumpkinseed were collected in
|
|
|
|
Figure
6‑13. 2010
Young-of-year Catch per Unit Effort (CPU) distribution by stratum and species.
Data indicate where young-of-year
fish were caught in the lake during 2010, as well as the percent of species
caught in each stratum.
Electrofishing
and gill net catches of largemouth bass in fall 2010 indicated that the majority
(69%) of angling-size largemouth bass in the lake are 8-15 inches in
length. The proportion of the population
from 15-20 inches increased by nearly 20% from 2009 to 2010 and now represents
nearly a third of the angling-size population.
Largemouth bass exceeding 20 inches are rarely collected during AMP
sampling efforts. This suggests that
fish of this size are rare in
The size distribution of smallmouth bass in the fall 2010
electrofishing and gill net catches was distinctly different from that of largemouth
bass, with the majority (60%) of angling-size fish being 7-11 inches in
length. However, the proportion (40%) of
smallmouth bass greater than 11 inches in fall 2010 was the highest it has been
since 2003. This increase was due
primarily to an increase in the number of 11-14-inch fish. The overall number of smallmouth bass
captured during fall sampling efforts has shown a steady decline since 2007,
but in 2010, the proportion of larger fish in this population increased
considerably. The current abundance and
size structure of the smallmouth bass population in Onondaga Lake provides
somewhat limited availability of smallmouth bass to anglers, but those fish
that are available provide relatively high angling quality. Analysis of smallmouth bass weight by size
class in 2010 indicates that smallmouth bass are in generally good condition
and above average in weight for their length.
Though not as abundant as largemouth bass,
The
fall 2010 electrofishing and gill net catches of sunfish (bluegill and
pumpkinseed) indicated that the population is dominated (99%) by fish of 3-8
inches in length. This has been the case since the AMP began in
2000. The fall 2010 data showed that the
proportion of sunfish 6-8 inches increased from 13% in fall 2009 to 22% in fall
2010. This means that currently a
greater proportion of quality-size sunfish are available to anglers than in the
previous year. This proportion may
increase further in 2011 as the large proportion (77%) of angling-size sunfish
less than 6 inches grow to quality size.
Sunfish
greater than 8 inches in the catch have been scarce. Several factors may be contributing to
this. It is possible that the selected
gear does not capture larger sunfish in proportion to their abundance. Larger adult sunfish tend to be more pelagic
than juveniles and smaller adults and may be captured disproportionately less
than these other groups when electrofishing littoral habitats. Slow growth of fish after reaching
reproductive age and competition for food with other species such as alewife and
gizzard shad may also be contributing to low abundance of larger sunfish in
Size distribution of yellow perch in the fall
2010 electrofishing and gill net catch indicated that the angling-size
population is dominated (88%) by fish 5-8 inches long. Yellow perch from 8-10 inches long comprise
10% of the angling-size population, and fish larger than 10 inches are rare. We
measured a similar size structure of the yellow perch population in 2006. This was followed by two years of increasing
proportions of fish 8-10 inches long and 10-12 inches long as the dominant year
class of smaller fish grew to maturity.
Increases in the proportion of yellow perch in the larger size classes
in 2011 and 2012 can be expected as the abundant year-class representing fish
5-8 inches ages. The overall abundance
of yellow perch has been increasing.
This coupled with a strong year-class that is approaching quality size
should translate to more and larger yellow perch being available to anglers in
the near future.
Electrofishing
and gill net catches of brown bullhead in fall 2010 indicated that
there is a relatively even distribution of angling-size fish among the 6-9 inch
(31%), 9-12 inch (40%), and 12-15 inch (28%) size classes. Nearly 70% of the angling-size fish are of
quality size (9 inches) or greater. This
affords anglers an opportunity to catch relatively large brown bullhead. Analysis of brown bullhead weight for various
size classes indicated that brown bullhead in Onondaga Lake are in generally
good condition, and their weight for a given length has shown an increasing
trend since 2008. The increasing overall number and individual relative weight
of brown bullhead in recent years has created the potential for a high-quality
brown bullhead fishery in
Largemouth
and smallmouth bass are the most popular game species in
Largemouth
bass angler catch rates in
Conversely,
smallmouth bass angler catch rates in
The
general lower angler catch rates of smallmouth bass from
The
occurrence of physical abnormalities in fish captured during AMP sampling is
monitored using a standardized protocol known as DELTFM. DELTFM abnormalities are defined as Deformities,
Erosions, Lesions, Tumors, Fungus, and/or Malignancies. Data are used for trend analysis and to
compare fish collected from
DELTFM abnormalities showed an overall increase
from 2003 to 2009, but decreased in frequency in 2010. DELTFM abnormalities were found in 0.6% of
adult fish from
Nineteen
species of adult fish were found with DELTFM abnormalities in 2010, exceeding
the previous high of 17 species in 2009.
One of these species was common carp, which had not previously been
included in fish examined for DELTFM abnormalities. The species contributing the most to the
DELTFM total in 2010 were brown bullhead (22% of total), largemouth bass (16%),
gizzard shad (12%), pumpkinseed (10%), and white sucker (10%). The decline in DELTFM abnormalities observed
in 2010 is due primarily to a decline in occurrence of abnormalities in brown
bullhead from 2009 to 2010 (Figure 6-14). This continues a decline in abnormalities in
this species that began in 2009.
Figure
6‑14. Relative importance of brown bullhead in
characterizing DELTFM abnormalities in
The
incidence of lesions and tumors in brown bullhead in
The
AMP collects a large amount of data each year related to the lake’s fish
community; lake managers, local scientists, university professors and others
use these data for teaching and research purposes.
The
The story of
The size structure of the zooplankton community is directly
affected by the alewife. The decrease in alewife biomass in 2008 and the first
part of 2009 allowed for the return of larger species of zooplankton, and had
subsequent effects on the structure of the phytoplankton community. Analysis of the 2010 data has indicated
another strong year class for alewife (2009 year class) that virtually eliminated
large zooplankton in 2010; the average size zooplankton in
Macrophyte coverage and abundance in
Of importance to anglers is the increase in largemouth bass in the electrofishing surveys and the decline in smallmouth bass in the littoral zone. Macrophyte coverage in 2010 appears to be reaching a density that is higher than the preferred range for largemouth bass, which may eventually lead to a reduction in the population of this gamefish.
In years of high alewife abundance, fish with pelagic larvae (such as pumpkinseed, bluegill, yellow perch and white perch) have shown reduced recruitment, which is likely due to predation of larvae by alewife when alewife abundance is relatively high. Analysis of larval trawl data indicate that only three species were collected throughout 2010, with the alewife dominant. Pumpkinseed larvae were collected in early June; bluegill larvae were collected in mid- and late-July, and larval alewife from early June to late July. The alewife, in turn, serve as forage for larger, fish-eating species such as smallmouth and largemouth bass, yellow perch, white perch, and walleye. Changes in the size distribution of smallmouth bass - in particular since 2000 - suggest that larger adults of this species may have shifted to deeper, offshore habitat from shallower, littoral habitat. The availability of alewife as forage in pelagic habitats may be facilitating this shift. If such a shift has occurred, this would reflect a change in adult smallmouth bass foraging from a littoral-based food web to a pelagic-based food web.
The proliferation of zebra and quagga mussels in the lake
after reductions in ammonia levels may be helping to support the increased
abundance of species like pumpkinseed by providing an abundant food
source. Other species such as freshwater
drum, yellow perch, and common carp that feed on mussels are also likely
benefitting from the increasing abundance of these mussels. All three species utilize both littoral and
pelagic areas; fishbase.org identifies yellow perch and common carp as
benthopelagic and freshwater drum as demersal. The AMP monitoring results
confirm this trophic classification; the three species are captured by
electroshocking in the littoral zone as well as by gill netting in the pelagic
zone Consumption of mussels by multiple fish species provides another
connection between the littoral-based food web and the pelagic-based food
web. The increasing complexity of the
overall food web in
In addition to the food web effects, dissolved oxygen (DO)
and temperature affect habitat availability for different species of fish,
which shapes the fish community structure of
Two metrics illustrate this approach:
(1) coldwater fish habitat (Figure 6-15(a)), and
(2) coolwater fish habitat (Figure 6-15(b)).
In both graphics, the blue color represents depth and
temporal location of water temperatures and dissolved oxygen concentrations
suitable for cold- and coolwater fish habitat, respectively. Yellow shows where and when temperatures are
out of range, while green shows where and when dissolved oxygen is out of
range.
Figure 6‑15. Fish space metric, 2010, for coldwater
and coolwater species.
Overall, there has been an increase in the quantity and
quality of habitat available to fish species in
The ACJ includes requirements for monitoring and modeling
the water quality conditions in the
As part of the annual AMP, water
quality conditions are monitored at Buoy 316 in the
Figure 7‑1. Three Rivers system study area.
Between late May and early November, 2010, water-quality
recording devices (YSI sondes) were deployed at Buoys 316, 236 and 409 to
measure in-situ dissolved oxygen, pH, salinity and temperature at 15-minute
intervals. Data from these locations
document ambient water quality conditions upstream of the “state cut”, an area
of prolific dreissenid mussels (Buoy 409), upstream of the Baldwinsville-Seneca
Knolls WWTP outfall and outlet of Onondaga Lake (Buoy 316), and downstream of
the lake outlet and Wetzel Rd WWTP outfall (Buoy 236). In addition to the high-frequency sonde
monitoring, three full water quality surveys were conducted in 2010 on July 29,
August 17 and September 21. Taken
together, these data portray water quality conditions in the
The higher salinity of
The
The year 2010 can be characterized as a relatively higher
flow year. Flow conditions in the
As a reference, the seven-day average low flow condition for
the
WEP personnel completed three water quality surveys of the
The 2010 summer discharge of the
Similar to 2009, there were seasonal differences between the July/August surveys and the September survey. The spatial patterns for the water quality parameters were more pronounced during the July and August surveys than they were during the September survey. The seasonal differences can be attributed to the changes in flow regime and the higher respiration rate of dreissenid mussels during the warmer July and August surveys.
Twelve violations of the NYSDEC instantaneous minimum DO standard of 4 mg/l were measured during the August 2010 survey (Table 7-1). There were no measured violations of the NH3-N or NO2 standards during the 2010 field program.
Table 7‑1. Summary of non-compliance with selected AWQS, Three Rivers, 2010. |
||||
Parameter |
Sampling
Date |
Location |
Depth |
Values
Out of Compliance (mg/l) |
Dissolved
Oxygen (Instantaneous Compliance Criteria = 4 mg/l) |
8/17/2010 |
Buoy-10 |
Bottom |
3.52 |
|
Buoy
-222 |
Bottom |
3.28 |
|
|
Buoy
-240 |
Bottom |
1.54 |
|
|
Buoy
-255 |
Bottom |
3.16 |
|
|
Buoy
-260 |
Bottom |
2.32 |
|
|
Buoy
-269 |
Bottom |
3.18 |
|
|
Buoy
-294 |
Surface |
3.97 |
|
|
|
Bottom |
1.79 |
|
|
Buoy
-316 |
Surface |
2.99 |
|
|
|
Bottom |
2.78 |
|
|
Buoy
-334 |
Surface |
3.69 |
|
|
|
Bottom |
3.19 |
|
Parameter |
Sampling
Date |
Location |
Depth |
Values
Out of Compliance (mgN/L) |
NO2-N (AWQS = 0.1 mg N/L) |
All
dates |
All
locations |
All
depths |
None |
Total
NH3-N AWQS calculated from pH and Temperature* |
All
dates |
All
locations |
All
depths |
None |
*The median value for NH3-N ambient water quality
standard in 2010 was approximately 1.2 mg N/L, ranged from 0.25 mg N/L to 1.8
mg N/L. |
In addition to the three extensive surveys in 2010, data from the in-situ sondes deployed in the Three Rivers indicate the frequency, magnitude and duration of low DO conditions. For days during which the sondes were in operation, the daily instantaneous standard of 4 mg/l was not met in 18%, 17%, and 28% of those days at Buoys 409, 316, and 236, respectively. Likewise, the daily average DO standard of 5 mg/l was not met in 14%, 22%, and 28% of those days. The frequency of such violations in 2010 was slightly less than that from 2009 at Buoys 409 and 316, but slightly higher at Buoy 236, due to low DO concentrations at the bottom layer measured during mid-August in 2010. Overall, the water quality conditions in 2010 exhibited an improvement in terms of regulatory compliance when compared with previous lower flow years (e.g., 2007).
(1) Develop a comprehensive revitalization, conservation and management plan for Onondaga Lake that recommends priority corrective actions and compliance schedules for the cleanup of Onondaga Lake; and
(2) Coordinate
the implementation of the plan by the State of
The plan for restoring Onondaga
Honeywell International, Inc. is
proceeding with remediation of legacy industrial pollution under regulatory
oversight. To date, efforts have focused on identification and removal of
sources to prevent additional contamination from reaching the lake. Now, the
remedial project effort is addressing contaminated lake sediments. Plans for
sediment dredging and capping in certain areas, mostly in the southern littoral
zone, are complete and dredging will begin in 2012. Information on the Honeywell
project submittals is available online at www.dec.ny.gov/chemical/37558.html on
the NYSDEC website.
Three inter-related water quality models, Onondaga Lake Water
Quality Model (OLWQM), Onondaga Lake Basin Model, and Three Rivers Water
Quality Model (TRWQM), are being used to evaluate the effectiveness of
restoration alternatives. The ACJ
required development, calibration and confirmation of these models using AMP
data. These models quantify the response of
The Onondaga Lake Basin Model http://pubs.usgs.gov/sir/2008/5013/SIR2008-5013.pdf is being used to analyze the effects that
proposed best management practices (BMPs) are likely to have on the loads of
phosphorus and nitrogen entering the lake. These BMPs will include both actions
on the landscape (for example, guiding land use changes) and actions to manage
hydrology (for example, through enhanced detention and storage). The link to
reports related to the Onondaga Lake Basin Model is http://ny.cf.er.usgs.gov/nyprojectsearch/projects/2457-AF3-1.html.
WEP
and the Onondaga
Environmental Institute (OEI) www.onondagaenvironmentalinstitute.org collaborated on an extensive
monitoring and surveillance
program designed to identify and, ultimately, remediate dry weather sources
of bacteria to the lower reaches of Onondaga Creek and Harbor Brook. Two phases
of the investigation have been completed, and additional monitoring is planned.
Samples were collected from seven sites along a five mile segment of Harbor
Brook, and 22 sites along a 24-mile segment of Onondaga Creek. Results have
pinpointed specific areas where bacteria are entering the creeks, and helped
direct remedial work on the aging wastewater collection infrastructure within
the City of
A conceptual design and
plan for revitalization of Onondaga Creek has been developed by
representatives of the City of Syracuse, Onondaga Environmental Institute,
Cornell Cooperative Extension of Onondaga County, Atlantic States Legal
Foundation, the SUNY College of Environmental Science and Forestry, and Canopy,
a coalition of parks associations and community gardens in the City of
Syracuse. Project information is available at www.esf.edu/onondagacreek/project.htm. The City of
The engineering improvements to the wastewater collection and treatment infrastructure continue to be the subject of professional and trade publications and presentations. In addition, scientists and academics continue to analyze this unique case study of rehabilitation of a once-degraded lake. The human health impacts and ecological analysis of the contaminant issues are of interest to academic and agency scientists, public policy specialists, economists, and engineers. An Onondaga Lake Symposium is convened each November by Upstate Freshwater Institute to discuss recent findings http://www.upstatefreshwater.org/html/annual_olsf.html.
Exploration of green technology
solutions to the challenges facing
As efforts continue to reduce
point and nonpoint sources of pollution to the lake, other projects are
underway to enhance recreational access and opportunities for community
involvement with the lake and its shoreline. Planning and design of Phase 1 of
the Creekwalk to connect
The AMP is not static;
Remedial measures to mitigate legacy pollutants are underway. Nitrate additions to the lake’s lower waters began in 2011, in an effort to modify the oxidation-reduction potential at the sediment water interface and delay mercury methylation. Plans to dredge sediments from the lake and restore aquatic habitat are proceeding, and will begin to affect the lake in 2011-2012. The restoration efforts will inevitably affect analysis and interpretation of the AMP biological and habitat data. The County will integrate the results of the Honeywell activities into the overall evaluation of the lake’s ecosystem, to the extent that data are made available. Any change to the County’s approach to data evaluation brought about by the Honeywell program will be documented in the Data Analysis and Interpretation Plan, which is part of the annual workplan submittal and included in the library of the Annual Report.
The Onondaga Lake Water Quality Model was developed and
calibrated using data from the AMP, and has been subject to outside expert peer
review. This model will serve the entire community by defining the water
quality and aquatic habitat benefits, if any, realized by further reducing
nutrient and sediment inputs from point and nonpoint sources. NYSDEC will use
this model to evaluate the environmental benefits, if any, associated with
additional phosphorus removal from Metro and watershed sources. This analysis
will support a TMDL allocation for phosphorus inputs to
In addition to the authors of the Annual Report, several
other individuals and professional service firms contribute their expertise to
the data collection and interpretation effort. We wish to acknowledge the
contribution of the following specialists for their ongoing commitment to
investigating the
(1) AirPhotographics Inc. of
(2)
Aquatic
Resources Center of
(3) PhycoTech Inc. of St. Josephs MI. Dr.
Ann L. St. Amand has been identifying the
(4) Racine-Johnson Aquatic Ecologists of
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Kishbaugh, S.A. 2009. NY State Citizens Statewide Lake Assessment
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