Transcript Document

Microbial Source Tracking Techniques:
Lake Michigan Beaches Case Studies
Erika Jensen, M.S.
Great Lakes WATER Institute
April 14, 2005
Potential Sources of E. coli
• CSOs, SSOs, and septic systems
• Urban and agricultural runoff
• Waterfowl, domestic pets, and wildlife
• Sand, algae, and interstitial waters
250,000-500,000 CFU/100 ml
Beach closure 235 CFU/100ml
240,000 CFU/100 ml
10,000-100,000 CFU/100 ml
368,000,000 CFU/g feces
GLWI Research Areas
Fate and transport of bacteria
Milwaukee Harbor, stormwater, Lake Michigan
Sources of pollution
Milwaukee Harbor, stormwater, Lake Michigan
Door, Manitowoc, Milwaukee, & Racine County Beaches
Pathogen occurrence
Bradford Beach, Racine, Milwaukee Harbor
Evaluation of BMPs
South Shore beach, green roofs and rain gardens
Approach to Microbial Source Tracking
1. Gather the experts and share knowledge
2. In depth spatial surveys
3. Targeted sampling to observe dynamics; modeling
4. Apply source tracking approaches:
•
•
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Human vs. non-human?
Are specific groups of animals contributing?
Does sand or Cladophora act as a reservoir?
5. Manage and evaluate the problem
Milwaukee River
Basin
• 900 sq mi watershed
• 410 miles of streams
• 1.3 million people
• Urban, industrial,
agricultural land uses
Bacterial Surveys
Spatial & Temporal
South Shore Beach Study: 2001 to present
Menomonee River Study: 2002
Fate and Transport Study: 2002 to present
Manitowoc & Door County Beach Surveys: 2002 - 2003
Bradford Beach Study: 2004 to present
South Shore Beach
Spatial surveys 2001-2004
Rain, N wind
CSO - 36 hrs, SE wind
No rain – SE Wind
CSO - 45 hrs, SE wind
2001
Dry weather (baseflow)
rivers
Wet weather (stormflow)
rivers
South Shore Beach
South Shore Beach
E. Coli Level Comparisons:
Current & Proposed Beach Sites
Menomonee River Study 2002
Determine river E. coli levels during
baseflow and stormflow

 Determine E. coli levels of inline
stormwater entering river
 Characterize “genetic profile” of E.
coli in stormwater
Menomonee River Survey
1
2
3
4
5
Suburban, suburban industrial
Natural bed
Urban,
Rehabilitated bed
6
7
8
9
10
Urban, industrial
Natural bed
Urban,
Concrete bed
E. Coli Data Menomonee River Survey
Fate & Transport
2003 Spatial Survey
Fate & Transport
CSO Event
May, 14 2004
Hydrodynamic
Model
• Hydrodynamics
- Transport
- Mixing
- Dilution
• Bacterial counts
Bacterial Die off in Lake Michigan
• Die-off is a 2nd
order function
• Die off in Lake
Michigan is 90% in
6-8 hours
Bradford Beach in Milwaukee
E. coli Survival & Persistence
in the Environment
Pre-rain 6-14-04 09:44
Post-rain 6-14-04 10:20
E. Coli in Sand
Range
8-39,000 E. coli/100 g
E. Coli Levels at Bradford Beach
Clonal Populations Suggest Growth
Pearson correlation (Opt:1.00%) [0.0%-100.0%]
100
80
Rep-PCR
60
40
Rep-PCR
1
2
3
E. Coli from Beach Sand
Bacteroides spp.
Case Studies
• Stormwater
• Beach water
• Agricultural Runoff
• Combined Sewer Overflows
Description
Beach Water –
Forested Area
Beach Water –
Resort Area
E. coli
Bacteroides spp. Human Cow
CFU/100ml
% Pos.
% Pos. % Pos.
300-680
100
17
0
42-190
100
0
0
1260-2500
100
0
50
Urban Beach –
No outfalls
450-600
100
0
0
Urban Beach –
with Outfalls
460-15,900
100
89
0
Parking Lot Runoff
300-50,000
100
0
0
Beach Water –
Agricultural land
Summary
•
Spatial surveys provide the most useful data
Identify hot spots or areas of concern
•
Implement targeted sampling surveys to observe
site specific dynamics
•
Apply source tracking approaches:
Human vs. non-human?
Are specific hosts contributing?
Are there environmental reservoirs?
•
Manage and evaluate the problem
Great Lakes WATER Institute
P.I., Dr. Sandra McLellan
Researchers
Annette Daniels
Alissa Salmore
Caitlin Scopel
Michelle Luebke
Pat Bower
Ola Olapade
Graduate Students
Marcia Silva
Sachie Owaga
Heidi Pirkov
Liang Peng
Sukpreet Kaur
Funding kindly provided by
Milwaukee Metropolitan Sewage District
Wisconsin DNR
National Institute of Health
NOAA Sea Grant
SC Johnson
Wisconsin Coastal Management Program
Students
Magnolia Tulod
Josh Harris
Elissa Lewis
Emerson Lee
Jennifer Lee
Andrew Holland
Becky Kirby
Hilary Street
Ben Weston
Morgan Depas
Meredith Van Dyke