John Mcloughlin managing director of NYC DEP office of Ecosystem services and Green infrastructure research gives updates on the research they have done on using natural features such as ribbed mussels to remove pathogens from water bodies
NYC DEP update on Ribbed Mussel potential for treating pathogens in water bodies
1. Jamaica Bay Task Force Meeting
November 13, 2019
John McLaughlin
Managing Director, Office of Ecosystem Services, Green Infrastructure and
Research
Natural Systems for Water Quality
Improvements:
Ribbed Mussel and Tidal Wetland Research
2. 2
Why Natural Systems?
Traditionally (and still do) solve the City’s need for water quality
improvements with large infrastructure solutions.
However, some new infrastructure projects come at a significant
cost, while achieving modest, incremental improvements as past
investments have already provided substantial cost effective water
quality improvements.
Therefore, sustainable and nature-based approaches need to be
part of the toolbox and a central theme that protects, preserves and
improves water quality while also providing substantial ecological lift.
3. 3
Comparison of Wetland Channels
Alley Creek
Wetland
Demonstration
Site
Primary Channel
Secondary Channel
Tertiary Channel
Primary Channel
4. 4
Tidal Wetlands and Pathogen Reduction
Research to evaluate tidal wetland
systems for their ability to remove
nutrients and Fecal Indicator
Bacteria (FIB) to improve water
quality.
Working with the Science and
Resiliency Institute at Jamaica
Bay (SRIJB)
Water Column and Sediment
parameters to be measured
include:
‒ Fecal Indicator Bacteria (FIB)
‒ Dissolved Oxygen
‒ Nitrogen and Phosphorus
‒ Total Suspended Solids
‒ pH
‒ Salinity
6. 6
Ribbed Mussels and Pathogen Reduction
DEP in coordination with the New York State Department Environmental Conservation (DEC),
Cornell University Cooperative Extension of Suffolk County and Stony Brook University is
evaluating the potential for using Guekensia demissa (Ribbed Mussel) for water quality
improvements.
Ribbed mussels are possibly unique among bivalves in also possessing the ability to filter and
digest free bacteria, potentially helping to exert top-down control of harmful pathogens
(Kreeger and Newell 1996, 2000).
Existing research confirms that ribbed mussels have removal efficiencies of greater
than 10% for particle sizes between 0.2 - 2 µm (within fecal coliform range of sizes):
8. 8
Experiment Overview
• Purpose of microcosm
lab experiments is to
study the effects of
individual variables on the
filtration efficiency of
ribbed mussels
• Test individual variables
in isolated setting
• Will inform design of
future lab and field
mesocosm experiments
1. Temperature (Completed)
2. Salinity (Completed)
3. Mussel Size (Completed)
4. TSS/Turbidity (Ongoing)
5. Fate of Microbial Absorption
9. 9
Microcosm Experiments
• Each experimental parameter tested over 4 days to
reach the desired number of replicates
• Levels determined from analysis of water quality data
from Bergen Basin and Thurston Basin Harbor Survey (5
to 7-years)
• Experimental parameters will test 3-4 levels
• Temperature: 15˚C, 21˚C, 28˚C (completed)
• Salinity: 5 ppt, 12.5 ppt, 20 ppt, 25 ppt (completed)
• Mussel Size: 30mm, 50mm, 70mm (completed)
• Turbidity/TSS: 12 mg/L (20µg Chlorophyll A), 12 mg/L (100µg
Chlorophyll A, 30 mg/L (20µg Chlorophyll A) (in progress)
10. 10
Microcosm Experiments - Flow Cytometry
• Flow cytometer screenshots demonstrate the distinction among types of bacteria and
beads
• Different fluorescent channel plots show the dispersion of particles as they react to
specific light wavelengths
E. faecalis
E. coli
Beads
The polystyrene microsphere beads are
5-6µm in size (size range that ensures
100% capture efficiency by the gills) and
are used to assess mussel filtration rate
11. 11
Microcosm Experiments - Flow Cytometry
20 ppt at 120 minutes (2 hours)Time 0
• Cytograms showing the bacterial counts at Time 0 and after 2 hours at the salinity
level of 20 ppt
• Preliminary data shows significant bacterial removal at 20 ppt (similar to what was
observed in temperature experiments)
13. 13
Microcosm Experiments - Temperature
Preliminary Microcosm Results – Temperature on E. coli
0
500
1000
1500
2000
2500
3000
3500
4000
0 20 40 60 80 100 120 0 20 40 60 80 100 120 150 180
E.coliParticleCounts
Time (min)
E. coli 28 C E. coli 21 C E. coli 15 C
Bacteria Pulse Higher bacterial counts
on second pulse due to
residual particles from
first pulse
Bacteria Pulse
14. 14
Microcosm Experiments - Temperature
0
200
400
600
800
1000
1200
1400
0 20 40 60 80 100 120 0 20 40 60 80 100 120 150 180
E.faecalisParticleCounts
Time (min)
E. faecalis 28 C E. faecalis 21 C E. faecalis 15 C
Bacteria Pulse
Bacteria Pulse
Preliminary Microcosm Results – Temperature on
Enterococcus faecalis
*Data undergoing QA/QC