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Joe’s Pond Beach E. coli Monitoring
History and Plan for 2013
2003
Purpose
Protecting swimmers from contracting an illness
while recreating
Why E. coli?
• Best available and cost effective approach developed to date
• EPA approved for fresh waters
• Used to infer likelihood water contains human pathogens that elevates risk to contracting swimming-related illness
Indicator of Fecal Contamination
• E. coli is a bacteria found in the intestines of humans and other warm-blooded animals
• When found in rivers, lakes, ponds, streams, or drinking water, it means that somehow fecal material has made its way into the water
Indicator of potentially infectious pathogens
• It isn’t the E. coli we are worried about
• It’s the other fecally transmitted pathogens like live viruses, bacteria, protozoans or worms that may also be present
Indicator: Not Direct Measure of Pathogens
• Many times pathogens cannot survive outside the intestines for long periods of time and therefore are not alive
• To be prudent, it is assumed that if E. coli is present, live contagious viruses or pathogens may have been present in the source fecal material and thus may now be in the water
Some E. coli is O.K.
• The joy of swimming outdoors
• Enjoyment of wide variety of wildlife
• Naturally, some ‘waste’ from wildlife makes it into our waterbodies
• This does not necessarily mean we are going to contract gastroenteritis or other illness from swimming in these waters
Factors Increasing Risk
• The more fecal contamination that enters a waterbody, the more likely that human viruses and pathogens are going to be present
• A very little amount of fecal material present, but if from an infected human, when contact by other swimmers occurs while pathogens still alive and viable
• Swimmer vulnerability: children, elderly, persons with reduced immune systems
What is an Acceptable Risk?
How do we know when the level of fecal contamination is high enough to increase our risk of illness to an unacceptable level?
Epidemiological studies
• Measure the amount of E. coli in swim waters
• Record the # of people who become ill afterwards
• Repeat over and over under a wide range of E. coli measurements
• Illness rate then related to amount of bacteria measured
EPA Standard
• 8 in 1,000 swimmers getting sick, EPA chose as acceptable level of risk
• Sample criterion at 235 E. coli organisms/100 milliliters (ml) of water
• By the federal criterion, as long as E. coli derived
from a single sample collection remains below 235 E. coli /100ml, waters are considered safe to swim in
• Conducted at very populated, urban beaches
• Some of the swimmers themselves were likely the source of the fecal contamination
• Beaches were also under the influence of nearby sewage discharges
• Human sources of fecal contamination
Epidemiological studies: Basis for EPA Standard
Human vs Non-human Fecal Sources • It is thought that human fecal material is more
likely to contain organisms that are pathogenic to humans than fecal material from other animals
• Don’t have the studies yet to tell us which warm-blooded animals carry organisms that are pathogenic to humans
Assume Risk is the Same • Risk from non-human fecal contamination
unknown
• Have to assume that non-human sources present the same risk as human sources
Advent of the Vermont Standard
• In 1986, the EPA published its national Ambient Water Quality Criteria for Bacteria document
• States were strongly encouraged to adopt the criteria or ones more stringent
EPA Recommended States:
Set illness rate of 8 per 1,000 swimmers
– Single sample 235 E. coli/100ml
– 5-sample geometric mean 126 E. coli/100ml
EPA Would Allow States:
Set illness rates up to 14 per 1,000 swimmers
– Single sample 1,021 E. coli/100ml
– 5-sample geometric mean of 548 E. coli/100ml
The Vermont Standard
Set illness rate to < 4 per 1,000 swimmers*
– Single sample 77 E. coli /100ml
*Based on EPA’s epidemiological studies
The Vermont Standard
• Standard legally binding when adopted in state’s water quality standards
• VT standard far more strict than EPA recommendation
• Most stringent standard in the nation
The Vermont Standard
• At 77 E. coli /100 ml, we can be 75% certain that 3.4 persons in 1,000 will get sick
• This assumes they are swimming at a beach with
– very heavy use and
– influence by some level of waste discharge
The Vermont Standard
• Vermont’s beaches aren’t like the ones in the epidemiological studies
• In Vermont, we no longer have beaches that are subject to sewage discharge and have thousands of human swimmers like those in the epidemiological studies used by EPA
Limits ability to assess real risks to Vermont swimmers
• Epidemiological studies performed at beaches unlike Vermont’s
• VT sources more likely to be non-human
• Pathogenic risk from non-human sources unknown, but thought less
• VT standard strictest in nation
VT Standard Exceeded in Undeveloped Watersheds
Recent local studies* found that after rainfall events, E. coli levels will exceed the state standard in waters draining completely undisturbed, forested watersheds
*Sargent and Morrisey, 2000; Moir, 2003
Preliminary Results: VT Undeveloped Watershed
Year N No. of
Events Min Max Median
Geometric
Mean Mean
2001 28
4 1.5 292 15.25 15.9 43.4
2002 27
4 2.1 436.2 82.2 53.5 115.6
Overall 55
8 1.5 436.2 24.0 28.8 78.8
Meghan Moir UVM Thesis, 2003
Good News
Swimming at waters that are regularly tested and posted in Vermont is probably safer than
swimming anywhere in the nation
Bad News
Sometimes beaches in Vermont are going to be closed when the risks to
becoming ill are very low
2004 Danville Town Health Officer Sampling Joe’s Pond Beach
2004 Joe's Pond Beach E. coli
0
50
100
150
200
250
7/6
/2004
7/1
3/2
004
7/2
0/2
004
7/2
7/2
004
8/3
/2004
8/1
0/2
004
8/1
7/2
004
8/2
4/2
004
E.
co
li p
er
100 m
l
U.S. EPA Standard (235 E.coli/100 ml)
VT Standard (77 E.coli/100 ml)
Town Health Officer samples, Danville pays for analyses, Lab and method used unknown
2005
2005 Kellie Volunteers to Sample for Town
• Given understanding of E coli
• Given transition in town health officer
• Given discussion at Town Meeting Day where Joe’s townspeople expressed the opinion that the beach was too polluted and hence the town should not buy it from the power company
2005
2005 Joe's Pond Beach E. coli
0
50
100
150
200
250
5/3
1/0
5
6/7
/05
6/1
4/0
5
6/2
1/0
5
6/2
8/0
5
7/5
/05
7/1
2/0
5
7/1
9/0
5
7/2
6/0
5
8/2
/05
8/9
/05
8/1
6/0
5
8/2
3/0
5
8/3
0/0
5
E.
co
li p
er
100 m
l
U.S. EPA Standard (235 E.coli/100 ml)
VT Standard (77 E.coli/100 ml)
Kellie Merrell volunteers, Danville pays for analyses, VTDEC laboratory analyzes using Quanti-Tray Method SM 9223 B
2006
Kellie Merrell volunteers, Danville pays for analyses, VTDEC laboratory analyzes using Quanti-Tray Method SM 9223 B
2006 Joe's Pond Beach E. coli
0
50
100
150
200
250
5/2
0/0
6
5/2
7/0
6
6/3
/06
6/1
0/0
6
6/1
7/0
6
6/2
4/0
6
7/1
/06
7/8
/06
7/1
5/0
6
7/2
2/0
6
7/2
9/0
6
8/5
/06
8/1
2/0
6
8/1
9/0
6
8/2
6/0
6
E.
co
li p
er
100 m
l
U.S. EPA Standard (235 E.coli/100 ml)
VT Standard (77 E.coli/100 ml)
2007
2007 Joe's Pond Beach E. coli
0
50
100
150
200
250
6/6
/07
6/1
3/0
7
6/2
0/0
7
6/2
7/0
7
7/4
/07
7/1
1/0
7
7/1
8/0
7
7/2
5/0
7
8/1
/07
8/8
/07
8/1
5/0
7
8/2
2/0
7
8/2
9/0
7
E.
co
li p
er
100 m
l
U.S. EPA Standard (235 E.coli/100 ml)
VT Standard (77 E.coli/100 ml)
Kellie Merrell volunteers, Danville pays for analyses, VTDEC laboratory analyzes using Quanti-Tray Method SM 9223 B
2008
Kellie Merrell volunteers, Danville pays for analyses, VTDEC laboratory analyzes using Quanti-Tray Method SM 9223 B
2008 Joe's Pond Beach E. coli
0
50
100
150
200
250
300
6/1
/2008
6/8
/2008
6/1
5/2
008
6/2
2/2
008
6/2
9/2
008
7/6
/2008
7/1
3/2
008
7/2
0/2
008
7/2
7/2
008
8/3
/2008
8/1
0/2
008
8/1
7/2
008
8/2
4/2
008
E.
co
li p
er
100 m
l
U.S. EPA Standard (235 E.coli/100 ml)
VT Standard (77 E.coli/100 ml)
2009
Kellie Merrell volunteers, Danville pays for analyses, VTDEC laboratory analyzes using Quanti-Tray Method SM 9223 B
2009 Joe's Pond Beach E. coli
0
50
100
150
200
250
300
6/1
8/2
009
6/2
3/2
009
6/3
0/2
009
7/8
/2009
7/1
6/2
009
7/2
1/2
009
7/2
9/2
009
8/5
/2009
8/1
1/2
009
8/1
8/2
009
8/2
4/2
009
8/3
1/2
009
E.
co
li p
er
100 m
l
U.S. EPA Standard (235 E.coli/100 ml)
VT Standard (77 E.coli/100 ml)
2010
Kellie Merrell volunteers, Danville pays for analyses, VTDEC laboratory analyzes using Quanti-Tray Method SM 9223 B
2011
Swimmer volunteers, Danville pays for analyses, NH Lab performs analyses, samples dropped off at Gould Drilling on Tuesday evenings for delivery to Endyne lab Wednesday mornings
Tuesday after Tropical Storm Irene
2011
Swimmer volunteers, Danville pays for analyses, NH Lab performs analyses, samples dropped off at Gould Drilling on Tuesday evenings for delivery to Endyne lab Wednesday mornings
Tuesday after Tropical Storm Irene
December 2011
• EPA releases a draft guidance for recreational water quality
• Scientific review of more than 20 years of data.
• Guidance value: E coli bacteria density should not exceed 235 colony forming units (cfu) per 100 ML of water
June 2012 Vermont Department of Health
• Issues Healthy Recreational Waters Report
• Uses latest science to set guidance recommending 235 be used instead of state’s standard of 77 for closing a beach
2012
Swimmer volunteers, Danville pays for analyses, NH Lab performs analyses, samples dropped off at Gould Drilling on Tuesday evenings for delivery to Endyne lab Wednesday mornings
2012
Swimmer volunteers, Danville pays for analyses, NH Lab performs analyses, samples dropped off at Gould Drilling on Tuesday evenings for delivery to Endyne lab Wednesday mornings
Same Method as VTDEC Lab
Sample tracking
• September 25, 2012 2:30 p.m. sample taken
• September 26, 2012 11:45 a.m. sample arrives at Endyne, 17 C temperature
• 21 hrs and 15 min after sample taken, it arrives at lab
• This is over the 6 hr hold time
Quanti-Tray Method SM 9223 B
VTDEC Lab
• Must get sample to lab within 6 hours of taking it! ‘Hold time’
• Must arrive at lab by 2 p.m. so sample processing can begin
• If exceed temperature upon arrival, sample is void
Endyne Lab
• Sample taken in afternoon, does not arrive at lab processing sample until next morning
• We only have data from one sample, but the temperature when it arrived at the lab was warm 17C.
EPA will allow the 6 hr hold time to be exceeded if:
• It has been demonstrated that no significant difference exists from samples processed with-in the normal 6 hour hold time
• This requires numerous samples to be taken simultaneously and processed at both the 6 and 30 hour hold times
Federal Clean Water Act Regulations require E. coli compliance samples to be analyzed by the laboratory within six (6) hours of sampling. Standard Methods and the Code of Federal Regulations (CFR) state that samples taken for analysis of E. coli, for the demonstration of compliance with NPDES permit requirements, are to be analyzed within six (6) hours of transport and two (2) hours of storage at 1-5oC at the laboratory. 40 CFR allows that samples may be held for longer periods only if the permittee or laboratory has data on file to show that, for the specific types of samples under study, the analytes are stable for a longer time and the permittee or laboratory has received a variance from the Regional Administrator under § 136.3(e).
Endyne Lab
• Exceeds hold time and temperature minimum
What do we know
• 2005 – 2010 we never came close to exceeding Vermont’s stringent standard
• 2011 we had our first exceedance of both the Vermont standard AND the EPA 235 standard in 8 years of monitoring. It seemed to be in response to Tropical Storm Irene.
• 2012 we had 3 exceedances of both the Vermont standard AND the EPA 235 standard. Two of which exceeded the maximum minimum standard EPA will allow a state to set its E coli threshold at (1,021) and one that came very close to it.
3 Exceedances in 2012 Could Be:
Wrong • Problem with the collection, holding time,
temperature, etc. • We will never know Real • If real, then what is the cause?
– Fecal material of some sort – Could be human, bird, cow, dog, cat, duck, etc. – We know there was a failed septic – We know the water level dropped unexpectedly due to dam – We will never know which
Determining the source
• Microbial Source Tracking
– In research stages
– Not commonly used
– Very expensive
Town of Danville
• Is doing the right thing by monitoring
• If the town doesn’t do it, no one is going to do it and swimmers will be unprotected
Next steps
1. Build our confidence in the sample results and continue sampling, add some observations simultaneous to sampling
2. Make a plan for seeking out sources when/if exceedance occurs
3. Seek out potential sources of fecal contamination for remediation
Build our confidence in the sample results Sampling Plan and Costs
• Sample every Tuesday at 7 a.m. again
• Memorial Day to Labor Day (14 weeks)
• $16 per sample
• Take 3 duplicates
• Total of $272 for sample analysis
Build our confidence in the sample results Getting Samples to Lab
• Need to be to UVM by 2 p.m.
• Need to get to UVM within 6 hr hold time
• Need to be transported on wet ice
• Need to retrieve sample coolers before next week’s sampling
Build our confidence in the sample results Green Mtn Messenger – W Danville Pick Up
• Immediate pick up at 7 a.m. in West Danville and delivered to UVM within 1.5 hours at 9:30 a.m.
• $95 per sampling date
• 14 sampling dates
• $1,330 total delivery costs
Build our confidence in the sample results Green Mtn Messenger – Montpelier Pick Up
• Kellie take sample at 7 a.m., meets GMM in Montpelier at 8 a.m.
• GMM delivers directly to UVM by 9 a.m.
• $65 times 14 sampling dates = $910
Problem is that Kellie doesn’t always go to Montpelier, many times she samples lakes in the NEK and meets crew in field
Additional Potential Costs
• If have an exceedance on Tuesday, will know on Wednesday
• Will take sample on Thursday and will need to have courier service deliver sample to UVM ($95 or $65 depending on where Kellie can meet them)
• Each additional sample is $16
Make a plan for seeking out sources if exceedance occurs
• Kellie’s notes during collection (counts of
geese, ducks, etc)
• Evidence of recent manure applications
• Evidence of failing septic systems
• Counts of waterfowl
• Mobilize West Danville Community Club, JPA and Town people to report these things
Seek out potential sources of fecal contamination for remediation
• Failing septic systems
• Manure discharges
• Waterfowl counts
• Dog waste management
• Etc…
Caution
• I would refrain from doing anything expensive or publically controversial until we have evidence that E coli is really exceeding the standard
• Obvious exceptions being when there is evidence that: – a septic system is failing it should be repaired or
replaced
– Manure is being directly discharged into the lake or inlet stream VT Agency of Agriculture should be called to stop it
Good Practices to Employ
• Educate lakeshore residents on importance of proper septic maintenance, signs of failing septics, and recommended pump out schedules
• On private properties, plant vegetative buffers as barriers to waterfowl coming on shore to use preferred lawn habitat
• At public beach, continue to educate users importance of not feeding waterfowl
Tom Dente’s Expectations
1. Give JPA members process to follow for identifying, treating and reporting failing septic systems
2. Is it Geese or Septic at the Beach?
3. Roles and Responsibilities
1. JPA
2. Town
3. State
Conclusions
• We will never know what was responsible for the exceedances in 2012
• All we can do is decide what to do from here on out. – Make sure we can’t question the data collected
– Work collectively when there is an exceedance to collect evidence about what are the likely sources
– Educate landowners and users on best management practices
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