Land-Based Evaluations of the Maritime Solutions, Inc.

Ballast Water Treatment System

Maritime(Environmental(Resource(Center

20 November 2009

c/o Chesapeake Biological Laboratory

PO Box 38, Solomons, Maryland 20688, USA

UMCES Technical Report Series: Ref. No. [UMCES]CBL 09-138
 MERC ER02-09

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Notice

The objective of this Maritime Environmental Resource Center (MERC) evaluation was 

to provide shipping lines, classification societies, regulators, and flag states with an independent 

and credible assessment of treatment performance under realistic conditions. Therefore, the 

ballast water treatment system was tested in accordance with the International Maritime 

Organization (IMO) International Convention for the Control and Management of Ships’ Ballast 

Water and Sediment (2004), Resolution MEPC.174(58) Guidelines for Approval of Ballast 

Water Management Systems (G8). The evaluation was conducted under specific, predetermined, 

agreed-upon protocols, criteria, and quality assurance procedures to assess the treatment system's 

performance.

MERC does not label or list technologies as acceptable or unacceptable but will present 

the results in an objective way that can be used to determine regulatory compliance by 

appropriate administrations, agencies or certification societies. Subsequent data on the 

technology's performance characteristics is presented to allow for comparison with the IMO

Convention discharge standards, Regulation D-2, Ballast Water Performance Standard. 

MERC and the MERC Advisory Board do not provide certification for technologies, or 

certify that a technology will always operate as demonstrated. Additionally, no expressed or 

implied guarantee is provided as to the performance of the technology, or that a technology will 

always operate at the levels verified. MERC does guarantee the levels verified during the 

evaluation under the conditions, circumstances, and operations encountered as fully independent 

and credible. 

This report has been reviewed by the MERC Advisory Board and provided to MSI and 

MERC funding agencies prior to public release. Mention of trade names or commercial products 

does not constitute endorsement or recommendation by MERC.

Questions and comments should be directed to Dr. Mario Tamburri, tamburri@umces.edu.
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Table of Contents

Page No.

1. MERC Background and Objectives...............................................................................1

2. Description of the MSI Ballast Water Treatment System .............................................1

3. Summary of IMO Standards..........................................................................................2

4. Summary of Test Protocols............................................................................................2

5. Summary of Results.......................................................................................................3

6. Results Trial 1................................................................................................................4

7. Results Trial 2................................................................................................................6

8. Results Trial 3................................................................................................................9

9. Results Trial 4..............................................................................................................11

10. Results Trial 5..............................................................................................................13

11. Acknowledgements......................................................................................................16
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1. MERC Background and Objectives

The Maritime Environmental Resource Center (MERC) is a State of Maryland initiative 

that provides test facilities, information, and decision tools to address key environmental issues 

facing the international maritime industry. The Center’s primary focus is to evaluate the 

mechanical and biological efficacy, associated costs, and logistical aspects of ballast water 

treatment systems and the economic impacts of ballast water regulations and management 

approaches. A full description of MERC’s structure, products, and services can be found at 

www.maritime-enviro.org.

To address the need for effective, safe, and reliable ballast water treatment systems to 

prevent the introduction of non-native species, MERC has developed as a partnership between 

the Maryland Port Administration (MPA), Chesapeake Biological Laboratory/ University of 

Maryland Center for Environmental Science (CBL/UMCES), U.S. Maritime Administration 

(MARAD), Smithsonian Environmental Research Center (SERC), and University of Maryland 

(UMD) to provide independent performance testing and to help facilitate the transition of new 

treatment technologies to shipboard implementation and operations. 

This report describes the MERC evaluation of the Maritime Solutions Inc. (MSI) Ballast 

Water Treatment System through objective and quality assured land-based testing (dockside at a 

flow rate of 200 m3/hr). The goal of this evaluation was to provide shipping lines, regulators, 

classification societies, and flag states with an independent and credible assessment of treatment 

performance under realistic conditions. Therefore, the data and information on performance 

characteristics covers legitimate information to meet the evaluation's objective, and performance 

is presented in a way to allow for comparison against the International Maritime Organization 

(IMO) International Convention for the Control and Management of Ships' Ballast Water and 

Sediments (2004), Regulation D-2 Ballast Water Performance Standard.

2. Description of the MSI Ballast Water Management System

The MSI Ballast Water Treatment System (UV), patent pending, is designed to meet

IMO D2 discharge standards for low to moderate flow rate shipboard applications. The 

treatment utilizes Ballast Safe Filtration Company's proprietary self-cleaning filter design to 

separate the components of the influent ballast water in its primary treatment stage. As a 

primary treatment, the filter is intended to remove silt and sediment, organic materials and

organisms > 25 μm (nominal) in size from the influent ballast water. The remaining filtered

water stream is then treated by Hanovia UV In-Line UV units in a secondary treatment stage to 

address the remaining organisms < 25 μm. In addition to its two treatment stages, the MSI 

System (UV) has been fully integrated and is controlled by a proprietary ABB Instrumentation 

water quality monitoring and flow control system designed to assure and document effective 

treatment by continuously monitoring a number of water quality parameters including total 

suspended solids (TSS) and UV transmission rate, automatically adjusting flow rate to assure 

proper treatment, and recording all required water quality and system operation parameters.

Because the treatment system was a prototype, it was operated at all times by members of the 

MSI or ABB staff. All evaluation system equipment and instrumentation, excluding the 

treatment system, was operated by MERC personnel.
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3. Summary of IMO Standards

This evaluation was designed to determine if the MSI system can meet IMO D2 standards 

in accordance with both the IMO Guidelines for Approval of Ballast Water Management Systems 

(G8). The IMO Convention performance standard states that ships must discharge:

1) Less than 10 viable organisms per m3, greater than or equal to 50 μm in minimum 

dimension;

2) Less than 10 viable organisms per ml, less than 50 μm in minimum dimension and greater 

than or equal to 10 μm in minimum dimension and

3) Less than the following concentrations of indicator microbes, as a human health standard:

1. Toxigenic Vibrio cholerae (serogroups O1 and O139), less than 1 colony forming unit 

(cfu) per 100 ml 

2. Escherichia coli, less than 250 cfu per 100 ml;

3. Intestinal Enterococci, less than 100 cfu per 100 ml.

4. Summary of Test Protocols

The following is a brief summary of the testing approach and methods. For complete 

details on protocols, data management, and quality control / quality assurance procedures for this 

MERC evaluation, please refer to the Test Plans for the Performance Evaluation of the Maritime 

solutions, Inc. Ballast Water Treatment System (April 2008 and March 2009), available for 

download at www.maritime-enviro.org.

The protocols described below are based upon the IMO G8 guidelines and the U.S. Coast 

Guard supported ETV protocols under development. Any deviation from IMO G8 or ETV were 

explained and justified in the Test Plan. MERC evaluated the biological efficacy of the MSI

ballast water treatment system onboard the MARAD vessel MV Cape Washington while docked 

in the Port of Baltimore. The ballast system on MV Cape Washington was modified to allow for 

water at a flow rate of 400m3

/hr to be split equally at flow rates of 200 m3/hr and delivered 

simultaneously to either a “control” (untreated) ballast tank or a “treated” (passing first through 

the MSI system) ballast tank. These two tanks were used for the required holding time of five 

days and were essentially identical in size and structure. Each tank was filled to approximately 

250 m3

 for each test trial.

Temperature, salinity, dissolved oxygen, chlorophyll fluorescence, turbidity and pH were 

measured every 15 minutes during the test trials by two identical multi-parameter probes placed, 

one each, into the control and test tanks. Initial inline samples of ballast water during the filling 

of the control and test tanks were collected, filtered, and analyzed for the water quality 

parameters of particulate organic carbon (POC), dissolved organic carbon (DOC – only in 2009), 

and total suspended solids (TSS).

A total of 10 identical 1.1 m3 conical bottom mesocosms were also used for controlled 

sampling during each trial. Using the mesocosms, five sequential samples were taken during: 

(A) initial filling of tanks, just prior to the split of control and treated water (T0 Control), (B) 

initial filling of test tank, just downstream of the MSI system during filling of test tank (T0 

Treated), (C) during discharge of control water after a five-day holding time (TF Control), and 

(D) during discharge of treated water after a five-day holding time (TF Treated). 

Immediately after filling, 1.0 m3 of water in each mesocosm was filtered through a 35 μm 

plankton net to concentrate the zooplankton for qualitative and quantitative analyses under a 

dissecting microscope. The proportion and total concentration of live versus dead organisms was 
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determined using standard movement and response-to-stimuli techniques within one hour of 

collecting the individual samples. Zooplankton samples were also fixed and returned to the 

laboratory for additional taxonomic evaluations. 

Ten liters of unfiltered water from each mesocosm were also collected immediately after 

filling, to determine concentrations of organisms in the 10 to 50 micron size class using four 

distinct methods: (A) One sub-sample was fixed with standard Lugol’s solution to determine 

total cell abundances under an inverted compound microscope using grid settlement columns and 

phase contrast lighting. (B) A second sub-sample was stained using CMFDA (5-

chloromethylfluorescein diacetate) as a selective live/viable indicator. Stained sub-samples were 

incubated and observed on a Sedgewick Rafter slide using a Leitz Laborlux S modified for 

epifluorescence. (C) A third sub-sample was filtered and frozen until analysis of total and active 

chlorophyll-a by the NASL. (D) Finally, a fourth sub-sample was used to determine chlorophylla levels after allowed to regrow under favorable conditions. An increase in chlorophyll, or 

positive regrowth, indicates that viable phytoplankton were in the samples, whereas chlorophyll 

levels at or below detection limits of the laboratory analytical method suggests that there was no 

viable phytoplankton. 

Additional 1-liter subsamples of unfiltered water were also collected from each 

mesocosm to determine concentrations of total heterotrophic bacteria and three specific indicator 

pathogens, E. coli, intestinal Enterococci, and toxigenic Vibrio cholerae. Total heterotrophic 

bacteria were enumerated by spread plate method using NWRI agar according to Standards 

Methods for the Examination of Water and Wastewater. The presence and abundance of E. coli

and intestinal Enterococci was determined using a commercially available chromogenic substrate 

method (IDEXX Laboratories, Inc.; Noble et al. 2003) and 10 ml and 100 ml water sample 

aliquots. Additionally, concentrations of culturable E. coli and intestinal Enterococci were 

determined using a standard USEPA method, namely, membrane filtration on mTEC agar (E. 

coli) (1 ml, 10 ml and 100 ml) and mEA agar (Enterococcus) (10 ml and 100 ml). Abundance of 

total and toxigenic V. cholerae were calculated by filtration and selection on TCBS agar and 

enumerated using species-specific RNA colony blot (500 μl to 1 ml) and ctxA DNA colony blot 

(1-10 ml). Viable toxigenic V. cholerae was assayed with a commercial DFA kit specific for 

serogroup O1 (New Horizons Diagnostics) using monoclonal antibodies tagged with fluorescein 

isothiocyanate (FITC) (Hasan et al. 1994).

5. Summary of Results*

The MSI Ballast Water Treatment System dramatically reduced the numbers of live 

organisms in ballast water during MERC land-based testing in the Port of Baltimore. For most 

biological categories, the treatment system consistently met IMO D2 discharge standards. 

However, while large reductions in the abundances of organisms greater than 50 μm were found, 

the T-Final average numbers of live zooplankton (> 50 μm) were not consistently below 10 μm 

in treated water after the 5-day holding time. The MSI system also experienced minor 

mechanical failures at different points during the testing process (broken in-line sensor housing 

and tripping of a circuit breaker). However, the failures were easily resolved with small 

modifications or repairs.

* Complete datasets and further performance information is available upon request.
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6. Results Trial 1 (MSI-05-08): 18-23 September 2008

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Initial Ave StDev Ave StDev Ave StDev

Conditions 5.0 0.5 - - 1.123 0.129

Note: Did not analyze for DOC in 2008

Temp oC Salinity psu Dis. Oxygen mg/l *Turbidity NTU

Ave StDev Ave StDev Ave StDev Ave StDev

T0 Control 24.5 0.0 11.7 0.0 3.9 .5 - -

T0 Treated 24.6 0.2 11.6 0.1 3.7 0.3 - -

TF Control 24.5 0.1 11.7 0.0 3.8 0.1 - -

TF Treated 24.7 0.1 11.6 0.1 3.3 0.1 - -

*Data not recorded in 2008

Live Organisms > 50 μm

T0 Ave #/m3 T0 StDev #/m3 TF Ave #/m3 TF StDev #/m3

Control 31,175 4,238 55,050 10,828

Treated 107 4.16 6 1.87

* Taxa listed in order of abundance.

Live Organisms 10 - 50 μm 

Vital Stain Results

Note: the CMFDA stain technique commonly underestimates the abundance of live 

organisms in this size class because not all live organisms reliably take up this stain. 

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control 530.7 122.5 11.2 2.3

Treated 7.3 0.6 0.6 0.7

*TF Control *TF Treated

Nauplii (copepod) Nematoda

Copepoda, Harpacticoida nauplii (copepod)

Copepoda, Cyclopoida Turbellaria

Copepoda, Calanoida

Nematoda

Rotifera
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Total Counts

This approach commonly overestimates the abundances of live organisms in this size 

class because all individuals in fixed samples are counted unless obviously dead (significant 

damage to organism).

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control Diatom 7,734 1,280 3,063 457

Dinoflagellate 578 223 134 49

Treated Diatom * 149 52

Dinoflagellate * 6 8

* Not yet analyzed

Note: 454/ml = Average counts for T-Final-Treated, for picoplankton <10μm.

Dominant species Type

Leptocylindrus minimum Diatom

Gyrodinium estuariale Dino

Eutreptia veridis Euglenid Flagellate

Thalassiosira sp. Diatom

Amphora sp. Diatom

Gonyaulux sp. (danicum?) Dino

Gyrodinium spirale Dino

Amphidinium sphenoides Dino

misc. Tinntinnids Ciliates

Active Chlorophyll-a

Chlorophyll is used as ancillary data and as a general presence/ absence indicator of 

viable photosynthetic organism. MDL = 0.56 μg

T0 Ave μg/l T0 StDev μg/l TF Ave μg/l TF StDev μg/l

Control 23.70 5.39 3.45 2.19

Treated * - 0.46 0.05

Regrowth Control - - 11.37 5.33

Regrowth Treated - - 0.04 0.01

*No initial treated data collected

Live Indicator Pathogens

CFU = colony forming units

E. coli

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 19.4 12.7 0.6 0.89

Treated * - 0 0

*No initial treated data collected
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Enterococci

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 5.66 - 13.58 -

Treated * - 0 -

*No initial treated data collected. No StDev reported.

V. cholerae

No detectable culturable toxigenic Vibrio cholerae were detected in any samples during 

any of the trials.

Total Heterotrophic Bacteria

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 31,833 7,591 98,288 90,638

Treated * - 6,936 6,586

*No initial treated data collected

7. Results Trial 2: (MSI-06-08) 2-7 Oct 2008

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Initial Ave StDev Ave StDev Ave StDev

Conditions 7.4 0.4 - - 0.474 0.042

Note: Did not analyze for DOC in 2008

Temp oC Salinity psu Dis. Oxygen mg/l *Turbidity NTU

Ave StDev Ave StDev Ave StDev Ave StDev

T0 Control 22.8 0.2 14.9 0.3 1.4 1.0 - -

T0 Treated 22.6 0.5 14.4 0.1 0.9 0.1 - -

TF Control 22.1 0.1 15.7 0.1 3.8 0.2 - -

TF Treated 22.4 0.1 14.7 0.1 4.5 0.8 - -

*Data not recorded

Live Organisms > 50 μm

T0 Ave #/m3 T0 StDev #/m3 TF Ave #/m3 TF StDev #/m3

Control 61,100 8,600 30,625 6,027

Treated 1370 120 2170 523

Note: Increase in numbers for T-Final treated counts likely due to hatch-outs of the egg bearing poicelistome 

copepod.
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* Taxa listed in order of abundance.

Live Organisms 10 - 50 μm 

Vital Stain Results

Note: the CMFDA stain technique commonly underestimates the abundance of live 

organisms in this size class because not all live organisms reliably take up this stain. 

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control 54.7 6.5 2.6 0.3

Treated 1.5 0.1 0.5 0.3

Total Counts

This approach commonly overestimates the abundances of live organisms in this size 

class because all individuals in fixed samples are counted unless obviously dead (significant 

damage to organism).

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control Diatom 849 176 520 161

Dinoflagellate 116 39 18 12

Treated Diatom * 83 16

Dinoflagellate * 4 4

*Not yet analyzed

Note: 365 #/ml = Average counts for T-Final-Treated, for picoplankton <10μm.

Dominant species Type

Leptocylindrus minimum Diatom

Gyrodinium estuariale Dino

Chaetoceros socialis Diatom

Thalassiosira sp. Diatom

Amphora sp. Diatom

Navicula didyma Diatom

misc. Pennates Diatom

misc. Tinntinnids Ciliate

*TF Control *TF Treated

nauplii (copepod) nauplii (copepod)

Polychaeta (larvae) Copepoda, Cyclopoida

Copepoda, Cyclopoida Copepoda, Poicelistomoida

Copepoda, Poicelistomoida

Copepoda, Calanoida

Rotifera

Bivalvia
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Active Chlorophyll-a

Chlorophyll is used as ancillary data and as a general presence/ absence indicator of 

viable photosynthetic organism. MDL = 0.56 μg

T0 Ave μg/l T0 StDev μg/l TF Ave μg/l TF StDev μg/l

Control 1.52 0.10 0.35 0.04

Treated * - 0.22 0.02

Regrowth Control - - 4.39 0.90

Regrowth Treated - - 0.01 0.00

*No initial treated data collected

Live Indicator Pathogens

CFU = colony forming units

E. coli

T0 Ave

cfu/100ml

T0 StDev 

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 10.6 13.56 1.4 1.52

Treated * - 0 0

*No initial treated data collected

Enterococci

T0 Ave 

cfu/100ml

T0 StDev 

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 24.84 - 14.28 -

Treated * - 0 -

*No initial treated data collected. No StDev reported.

V. cholerae

No detectable culturable toxigenic Vibrio cholerae were detected in any samples during 

any of the trials.

Total Heterotrophic Bacteria

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 12,150 6,954 11,920 6,633

Treated * - 7,860 8,308

*No initial treated data collected
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8. Results Trial 3: (MSI 01-09) 16-21 April 2009

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Initial Ave StDev Ave StDev Ave StDev

Conditions 7.33 0.50 3.62 0.24 0.84 0.07

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU

Ave StDev Ave StDev Ave StDev Ave StDev

T0 Control 10.3 0.3 9.8 0.1 8.4 0.1 4.4 0.2

T0 Treated 10.4 0.1 9.8 0.0 8.4 0.5 4.2 0.1

TF Control 13.1 0.1 10.0 0.1 8.6 0.1 1.6 0.1

TF Treated 13.3 0.1 9.3 0.1 9.5 0.1 3.2 0.1

Live Organisms > 50 μm

T0 Ave #/m3 T0 StDev #/m3 TF Ave #/m3 TF StDev #/m3

Control 179,000 49,518 127,933 21,624

Treated 200 288 8 5

*Taxa listed in order of abundance.

Live Organisms 10 - 50 μm 

Vital Stain Results

Note: the CMFDA stain technique commonly underestimates the abundance of live 

organisms in this size class because not all live organisms reliably take up this stain. 

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control 72.7 38.5 22.3 3.7

Treated 10 4 0.4 0.1

*TF Control *TF Treated

Calanoida (Eurytemora affinis) Calanoida

Copepoda nauplii Harpacticoida

various eggs Copepod nauplii

Cirrepedia nauplii

Rotifera

Ploychaeata (Spionidae)

Harpacticoida
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Total Counts

This approach commonly overestimates the abundances of live organisms in this size 

class because all individuals in fixed samples are counted unless obviously dead (significant 

damage to organism).

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control Diatom 41 17 48 18

Dinoflagellate 21 12 16 4

Treated Diatom 22 15 3 2

Dinoflagellate 10 10 1 1

Note: 2552 #/ml = Average counts for T-Final-Treated, for picoplankton <10μm.

Dominant species Type

Amphora sp. Diatom

Gyrodinium estuariale Dino

Thalassiosira sp. Diatom

Heterocapsa rotundatum Dino

Active Chlorophyll-a

Chlorophyll is used as ancillary data and as a general presence/ absence indicator of 

viable photosynthetic organism. MDL = 0.56 μg

T0 Ave μg/l T0 StDev μg/l TF Ave μg/l TF StDev μg/l

Control 6.20 0.51 2.99 0.38

Treated 5.25 0.46 2.44 0.14

Regrowth Control - - 60.00 27.31

Regrowth Treated - - 0.07 0.09

Live Indicator Pathogens

CFU = colony forming units

E. coli

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 22.40 2.70 0.20 0.45

Treated 0.00 0.00 0.00 0.00

Enterococci

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 21.14 8.43 10.12 4.93

Treated 0.2 0.45 0.00 0.00

V. cholerae

No detectable culturable toxigenic Vibrio cholerae were detected in any samples during 

any of the trials.
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Total Heterotrophic Bacteria

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 1,593.00 4,796.51 556.00 1,672.98

Treated 75.30 22.74 162.00 39.25

9. Trial 4 (MSI-02-09) 23-28 April 2009

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Initial Ave StDev Ave StDev Ave StDev

Conditions 30.13 3.69 3.57 0.34 1.10 0.04

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU

Ave StDev Ave StDev Ave StDev Ave StDev

T0 Control 11.3 0.1 10.4 0.2 6.4 0.3 8.6 0.3

T0 Treated 11.5 0.1 10.5 0.3 6.4 0.3 8.8 0.3

TF Control 13.8 0.1 10.5 0.0 7.4 0.1 1.3 0.4

TF Treated 13.8 0.1 10.3 0.1 8.4 0.1 5.7 0.2

Live Organisms > 50 μm

T0 Ave #/m3 T0 StDev #/m3 TF Ave #/m3 TF StDev #/m3

Control 117,000 32,786 47,167 3,329

Treated 158 53 *516 103

*Increase in treatment numbers due to an increase in newly hatched cirrepedia nauplii.

* Taxa listed in order of abundance.

*TF Control *TF Treated

Calanoida (Eurytemora affinis) Calanoida

Copepoda nauplii Cirrepedia nauplii

Cirrepedia nauplii Copepoda nauplii

Gastropod larvae Rotifera

various eggs
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Live Organisms 10 - 50 μm 

Vital Stain Results

Note: the CMFDA stain technique commonly underestimates the abundance of live 

organisms in this size class because not all live organisms reliably take up this stain. 

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control 1,259 88 68 20

Treated 91 26 12 5

Total Counts

This approach commonly overestimates the abundances of live organisms in this size 

class because all individuals in fixed samples are counted unless obviously dead (significant 

damage to organism).

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control Diatom 764 176 211 80

Dinoflagellate 255 47 106 24

Treated Diatom 324 137 38 6

Dinoflagellate 128 46 18 2

Note: 2489 #/ml = Average counts for T-Final-Treated, for picoplankton <10μm.

Dominant species Type

Heterocapsa rotundatum Dino

Gyrodinium estuariale Dino

Prorocentrum minimum* Dino

Chaetoceros sp. Diatom

misc. Copepod nauplii

Microcystis sp.* (4-5 μm) Cyanobacteria

* Know harmful algal species.

Active Chlorophyll-a

Chlorophyll is used as ancillary data and as a general presence/ absence indicator of 

viable photosynthetic organism. MDL = 0.56 μg

T0 Ave μg/l T0 StDev μg/l TF Ave μg/l TF StDev μg/l

Control 10.22 0.44 1.11 0.17

Treated 8.76 1.41 5.56 0.25

Regrowth Control - - 16.39 5.58

Regrowth Treated - - 0.12 0.03
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Live Indicator Pathogens

CFU = colony forming units

E. coli

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 19.40 26.57 1.40 0.89

Treated 0.00 0.00 0.00 0.00

Enterococci

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 61.44 11.48 13.72 1.94

Treated 0 0.00 0.00 0.00

V. cholerae

No detectable culturable toxigenic Vibrio cholerae were detected in any samples during 

any of the trials.

Total Heterotrophic Bacteria

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 533.00 1,624.82 271.25 947.93

Treated 92.80 18.14 116.88 24.22

10. Trial 5 (real trial MSI -03-09) 30 April – 5 May 2009

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Initial Ave StDev Ave StDev Ave StDev

Conditions 9.27 5.66 3.95 0.10 1.22 0.17

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU

Ave StDev Ave StDev Ave StDev Ave StDev

T0 Control 17.32 0.03 7.41 0.00 8.86 0.13 2.8 0.1

T0 Treated 17.51 0.00 7.34 0.00 9.13 0.01 2.8 0.1

TF Control 15.73 0.01 7.49 0.00 6.77 0.02 1.3 0.1

TF Treated 15.81 0.00 7.33 0.00 7.33 0.09 1.6 0.1
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Live Organisms > 50 μm

T0 Ave #/m3 T0 StDev #/m3 TF Ave #/m3 TF StDev #/m3

Control 113,500 9,674 51,500 4,515

Treated 38 7 *27 11

*All live individuals found were Acartia.

* Taxa listed in order of abundance.

Live Organisms 10 - 50 μm 

Vital Stain Results

Note: the CMFDA stain technique commonly underestimates the abundance of live 

organisms in this size class because not all live organisms reliably take up this stain. 

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control 1,944 174 280 35

Treated 149 27 11 3

Total Counts

This approach commonly overestimates the abundances of live organisms in this size 

class because all individuals in fixed samples are counted unless obviously dead (significant 

damage to organism).

T0 Ave #/ml T0 StDev #/ml TF Ave #/ml TF StDev #/ml

Control Diatom 417 186 281 47

Dinoflagellate 799 173 202 40

Treated Diatom 134 45 21 0

Dinoflagellate 285 66 17 7

Note: 1547 #/ml = Average counts for T-Final-Treated, for picoplankton <10μm.

*TF Control *TF Treated

Calanoida (Acartia tonsa) Copepoda nauplii

Cirrepedia nauplii Cirrepedia nauplii

Copepoda nauplii Calanoida (Acartia tonsa)

Polychaeta (Spionidae) Polychaeta (Spionidae)

Harpacticoida Harpacticoida 

various eggs
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* Know harmful algal species.

Active Chlorophyll-a

Chlorophyll is used as ancillary data and as a general presence/ absence indicator of 

viable photosynthetic organism. MDL = 0.56 μg

T0 Ave μg/l T0 StDev μg/l TF Ave μg/l TF StDev μg/l

Control 23.10 1.84 2.21 0.19

Treated 18.80 1.39 7.23 0.10

Regrowth Control - - 11.75 5.53

Regrowth Treated - - 0.17 0.12

Live Indicator Pathogens

CFU = colony forming units

E. coli

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 2.20 1.10 1.00 1.71

Treated 0.00 0.00 0.00 0.00

Enterococci

T0 Ave cfu

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu /100ml

TF StDev 

cfu/100ml

Control 2.62 1.17 3.9 0.84

Treated 0 0.00 0.00 0.00

V. cholerae

No detectable culturable toxigenic Vibrio cholerae were detected in any samples during 

any of the trials.

Total Heterotrophic Bacteria

T0 Ave 

cfu/100ml

T0 StDev

cfu/100ml

TF Ave 

cfu/100ml

TF StDev 

cfu/100ml

Control 208.75 716.73 192.20 33.08

Treated 116.88 24.22 145.30 44.39

Dominant species Type

Gyrodinium estuariale Dino

Prorocentrum minimum* Dino

Heterocapsa rotundatum Dino

Gymnodinium sp. Dino

Gyrodinium sp. Dino

Amphidinium sp. Dino

Amphora sp. Diatom

Microcystis sp.*(4-5 μm) Cyanobacteria

misc. Tinntinnids Ciliates
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11. Acknowledgments

MERC Testing Team included J. Barnes, M. Carroll, J. Choi, D. Fisher, C. Grim, B. 

Haley, A. Huq, R. Kanzleiter, T. Mullady, G. Ruiz, G. Smith, D. Sparks, M. Tamburri. E. 

Taviani, M.C. Wilkinson, L. Yonkos, and G. Ziegler. We wish thank the crew of the M/V Cape 

Washington who provided critical input on all aspects of these trials, and the Maryland Port 

Administration and U.S. Maritime Administration for funding and supporting this ballast water 

treatment evaluation.

November 20, 2009

November 20, 2009

Date Approved By: Dr. Mario Tamburri

MERC Executive Director

Date Approved By: Ross Kanzleiter

MERC Program Coordinator and

Chief Engineer