Timeline of Savannah Harbor
Expansion Project
Hydrodynamic
&
Salinity and Dissolved Oxygen Modeling
This
page
is intended to organize and present links to the modeling events that
have
occurred for the project in chronological order. As much as possible,
the records
that were created at the time represent the events. This requires
effort to open each document, but provides
the most objective presentation of what transpired.
General Information
(Click
on the link to go to this section,
which contains background information on the modeling.)
Feasibility study modeling
(Click on the link to
go to this section,
which runs
from March 1997
through the submission of the Final Feasibility Study Report and Tier I
EIS in
September 1998.)
Post feasibility study modeling
(Click on the link to
go to this section,
which runs
from the submission of the final Feasibility Study Report
and Tier I EIS in September 1998 and the initiation of the USACE
General
Reevaluation Study and Tier II EIS preparation that commenced with the
execution of a Memorandum of Understanding between the USACE and the
GPA in
July 2001.)
| The
links below will take you to the specific month. |
||
| Jul 1999 | ||
| Aug 1999 | ||
| Oct 1999 | |
|
| Nov 1999 | |
|
General Reevaluation Study modeling
(This period covers the time
from the execution of the Memorandum of
Understanding between the USACE and the GPA in July 2001 to the present.)
| The links below will take you to the specific month. | |||
| May
2005 |
|||
| |
|||
| |
|||
| |
|||
| |
|||
| |
|||
| |
|||
| |
|||
(Top)
As the Georgia Ports Authority (GPA) started the Feasibility Study for
the Savannah
Harbor Expansion Project, it was decided that the dynamic response of
the Lower
Savannah River estuary to deepening projects could not be predicted
based
solely on historic observations of this complex system. Prediction
would
require a reliable physical or numerical model for use as a simulation
tool for
the changes that could occur as a result of increasing the authorized
depth of
the navigation channel.
The primary concerns of the study team
were
focused on the intrusion of saline water into the estuary as the tidal
conditions changed, particularly how far saline water would penetrate
the
estuary and the duration of such penetrations. It was clear that
previous
modifications to the estuary, including a channel depth increase to 42'
MLW in
1992, the installation of and subsequent removal of the Tidegate from
service,
and channel widening had affected the environment with the Savannah
National
Wildlife Refuge (SNWR) being particularly sensitive to salinity.
A three dimensional numerical modeling
system,
WQMAP from Applied Science Associates, Inc., was chosen to meet the
study
needs. According to ASA's website (http://www.wqmap.com):
"WQMAP
is an integrated modeling system designed to study surface water
quality
issues. The system allows the engineer or scientist to develop
numerical grids,
perform hydrodynamic simulations, conduct single constituent pollutant
transport and multiple constituent eutrophication studies in a
geographic
context all from one application."
The WQMAP modeling system features
include:
1.
Incorporates
USEPA WASP
kinetic rate equations
2.
Includes
Ammonia, Nitrates,
Phosphates, Biological Oxygen Demand (BOD), Dissolved Oxygen (DO),
Organic
Nitrogen, Organic Phosphorous and Phytoplankton in its species
(Top)
This period runs from March
1997
through the submission of the Final Feasibility Study Report and Tier I
EIS in
September 1998.
Model Calibration and Validation
The Hydrodynamic and Salinity (H&S)
model was
calibrated by:
The Dissolved Oxygen (DO) model was
calibrated by:
Validation was performed with an
independent set
of data to determine how well the model could predict the distribution
of the
model variables. A series of tests were used to provide measures for
the
success of the calibration and validation steps. The first test was to
perform
a sensitivity analysis to determine which parameters and coefficients
were most
important in the Savannah Harbor simulations. Values were changed by
+10 percent
or +50 percent, individually, to determine their effect on model
results.
The second type of testing used actual
measures of
fit between field data and model results. These tests had been used
successfully for some years and included the following:
Monitoring and Data Collection
Data sets that had been collected by the
USGS and
the USACE, Savannah District were reviewed and judged to not adequately
quantify these characteristics, which were deemed critical to the
modeling
effort:
A monitoring program to collect and
provide sufficient
data for model calibration and validation was developed and presented
to
representatives of the U.S. Fish and Wildlife Service (USFWS), GA.
Department
of Environmental Protection (GAEPD), GA Department of Natural Resources
(GADNR), U.S. Environmental Protection Agency (Region IV) (EPA) and
local
industry representatives.
The monitoring and data collection
lasted
approximately two months during late summer (July - September) of 1997.
Bathymetry survey data was provided by Savannah District, USACE
personnel. This
was used, along with annual navigation channel survey data and aerial
photography to
define the geometry for modeling. Water quality data was collected at
the
upstream (I-95 bridge for water quality and Clyo for hydrodynamic) and
downstream (offshore extent of the navigation channel) boundaries.
Water
surface elevation measurements were made using 3 gages installed by the
U.S.
Geologic Service (USGS) and 8 additional gages placed along the Front
River,
South Channel and Middle River. Additional gages were placed in the
freshwater
marshes in the Savannah National Wildlife Refuge (SNWR) to quantify the
propagation of tidal cycles between the main channel and the marshes.
Two
continuous recording flow-measuring instruments were placed, one in the
upper
portion of the Front River and the other near Fort Jackson. A series of
water
quality and salinity instruments were placed to collect data
supplemented by
boat surveys and data collection.
Technical Advisory Group
A series of technical meetings were held
focusing
on the computer modeling and field data collection efforts that were
conducted
to characterize the hydrodynamic, chemical, and biological aspects of
the
Savannah River estuary. This group was informally named the Technical
Advisory
Group (TAG). These meetings were attended by local, state, and federal
agency
representatives and were a source of information and advice about model
development as well as a forum for communication amongst interested
entities.
Natural Resources Group
Another informal group, dubbed the
Natural
Resources Group (NRG), was formed to discuss the application of the
hydrodynamic model results to evaluate the potential biological impacts
on the
estuary. This group was instrumental in the selection of river flows
for
critical biological periods that were used in the H&S model
simulations.
Calibration
The model
was
calibrated to the tides, flows, currents and salinity data that were
collected.
The details of the calibration and the data used are contained in a
report
titled: "Hydrodynamic and Water Quality Modeling of the Lower Savannah
River Estuary" prepared by Applied Technology & Management (ATM).
Because how vertical mixing was addressed becomes a key concern in
2003, a
section of text from the July 1998 modeling report states:
"Due
to the highly dynamic nature of the stratification/destratification
processes
within the Lower Savannah River Estuary, and the inability for standard
turbulence formulations to capture them, a modified vertical turbulence
formulation was developed. A detailed discussion of this
turbulence
formulation is presented in Appendix B."
ATM personnel raised the issue to the
Technical Review Group because it
was
recognized that the methodology utilized was not a standard
method. The
standard methods available to ATM at that time were unable to capture
the
highly dynamic nature of the system relative to salinity, and, given
the need
for accuracy that was repeatedly stressed to our modelers, ATM chose to
develop
a more site-specific formulation for the Savannah Estuary. The
consensus
at the time within the Technical Advisory Group was that while one
would prefer
that standard turbulence methods be used, the method seemed reasonable
and
appeared to work for this system. The complete report may be
reviewed here.
H&S Simulations
To evaluate the changes in salinity
intrusion
caused by a deeper channel, model simulation runs were conducted using
the
following conditions:
Detailed conclusions regarding the
changes in
salinity and dissolved oxygen resulting from a deeper channel are
presented in
the Tier I Environmental Impact Statement (EIS), Section 5.3.1
Salinity. In
general, the simulations showed an increase in the upriver extent of
the .5 ppt
salinity concentration during tide cycles. (The value of .5 ppt
salinity was
used to characterize the salt/fresh water interface.) The Tier I EIS
may be reviewed here.
DO Simulations
To evaluate the changes in DO
concentration, the
hydrodynamic output files from the H&S simulation runs were used as
input
forcing files for the WQMAP DO model simulations. A detailed discussion
of the
methodology and conclusions is contained in the Tier I EIS, Section
5.3.2
Dissolved Oxygen (DO). In general, the simulations predicted reduced
mixing of
the water column and a small decrease in the DO concentration for a
deeper
channel.
The model report for this
effort
can be accessed here.
Post Feasibility Study Modeling
(Top)
This period runs from the submission of the final Feasibility
Study Report
and Tier I EIS in September 1998 and the initiation of the USACE
General
Reevaluation Study and Tier II EIS preparation that commenced with the
execution of a Memorandum of Understanding between the USACE and the
GPA in
July 2001.
In his endorsement submitting the
Feasibility
Study Report, the Chief of Engineers included: "... refinement of the
hydrodynamic model and concurrence by the U.S. Army Corps of Engineers
and the
natural resource agencies in the model's ability to reasonably predict
the
impacts of the proposed project alternatives, including mitigation
features." The complete report may be reviewed here.
In addition, comments submitted in
response to
review of the draft Tier I EIS pointed out needs for additional
refinement of
the H&S and DO models.
January 1999
At the first Stakeholders Evaluation Group meeting in January 1999, GPA
presented its recommendations for a DO field study to the SEG for
consideration. This proposal was titled:
Additionally, the GPA
proposed and
the SEG concurred in the formation of a group of modeling experts to
review the
study proposal and provide recommendations to the SEG. That group was
titled
the Modeling Technical Review Group and included representatives from:
February
1999
The MTRG reported to the SEG that it had agreed on the schedule and
content of
studies for dissolved oxygen, salinity and chlorides. They further
reported
they expected to present a study plan to the SEG by 1 May 1999. The
MTRG
recommended establishment of an Internet site for the posting of all
documents
to expedite their review and distribution and the dissemination of
information.
ATM established that site on Feb 1, 1999. The Feb 5, 1999 MTRG
meeting report can be reviewed here.
The Feb 26, 1999 MTRG meeting report may be reviewed here.
(Top)
March 1999
The MTRG forwarded several recommendations to the SEG via email,
including that the monitoring plan be further developed
after the
start of the field data collection, which was scheduled to occur in
early April
1999. The email with the recommendations can be reviewed here.
April 1999
The SEG gave interim approval of the DO field data collection task in
the April
1999 SEG meeting, subject to resolution of concerns with effects of
dredging on
data collection and collection of additional upstream and Back River
data. The
MTRG took up review of the model development task statements:
(SEG
meeting report
April
1999)
(Top)
August 1999
Data collection commenced.
October
1999
The field data collection was completed by October 9, 1999. It had been
extended over its initial scheduled completion due to the approach of a
hurricane in September 1999.
November 1999
The MTRG met on November 18, 1999 and agreed upon a review process for
model
development based on the task statements SEGDO1 and SEGDO2.
The
proposed
roles and activities of the MTRG through the execution of the task
statements
were:
"The MTRG will meet on a regular basis and ATM will provide to the MTRG
updates on the progress of the Model development. The MTRG will provide
review
and recommendations on the work completed based upon the progress
reports and
interim deliverables presented by ATM. The MTRG will be an active
participant
in the determination and development of the model coefficients, inputs,
and
comparison methodologies. This will be done through the review process.
The
goal will be to develop stepwise review and recommendations, such that
upon
completion of the model development, the MTRG is in agreement with the
coefficients, inputs, and accuracy of the hydrodynamic, water quality,
and
chloride models. The submittal and approval, therefore, of the final
model
development reports should be complete by the end of this stepwise
review
process. This will eliminate the need for substantial alteration of the
model
upon completion and expedite the overall review process. Additionally,
if
representatives of the various stakeholders are required to develop
their
review opinions in the light of review by other technical experts, this
will
reduce the amount of non-technically based opinions, maximize the
credibility
of the model verification and allow all stakeholders to represent their
positions through a qualified expert review process...."
The MTRG meeting report
may be reviewed here.
December 1999
Due to the highly dynamic nature of the
stratification/destratification
processes within the Lower Savannah River Estuary, and the inability
for
standard turbulence formulations to capture them, a modified vertical
turbulence formulation had been developed in 1997-1998. This unique
turbulence
parameterization was based on a log law fit of the vertical mixing
coefficients
to the tidal energy in the system. The methodology was presented
in a paper
in
the Estuarine and Coastal Modeling Section of ASCE, a peer-reviewed
journal
(this is the Mendelsohn et al., 1999 reference).
January 2000
The MTRG met on January 20, 2000 to:
(Top)
March 2000
The MTRG met on March 1, 2000 (MTRG status report of 3/1/00) to:
The MTRG met again on
March 30,
2000 (MTRG status report of 3/30/2000)
to:
June 2000
An MTRG meeting was held on Thursday, June 22, 2000 in Atlanta, GA at
the EPA
office (MTRG status report of 6/22/2000).
The
goals of the meeting were as follows:
The Federal agencies
associated
with the Savannah Harbor Expansion project prepared the first draft of
the
Federal Agencies Expectations and circulated it for internal review
amongst the
agencies.
August 2000
An MTRG meeting was held on Tuesday, August 29, 2000 (MTRG status report of 8/29/00) in
Atlanta,
GA at the EPA office. The goals of the meeting were as follows:
October
2000
An MTRG meeting was held on Thursday, October 5, 2000 (MTRG status report of 10/5/00) in
Atlanta, GA at the EPA office. The goals of the meeting were as follows:
The final field data
collection
report, titled 1999
Hydrodynamic and Water Quality Monitoring Report was delivered
to the
MTRG.
November 2000
An MTRG meeting was held on Monday, November 13, 2000 (MTRG status report of 11/13/00)
in Savannah,
GA at the USACE offices. The goals of the meeting were as follows:
(Top)
January 2001
An MTRG meeting was
held on
Wednesday, January 17, 2001 in
Atlanta,
GA at the USEPA offices. The goals
of the meeting were as follows:
At that meeting, Jim
Greenfield stated EPA intended to request the raw data presented in the
1999
Hydrodynamic and Water Quality Monitoring Report be made
available in
database or ASCII format. The MTRG status report may be reviewed here.
Attachment A is available here.
Attachment B is available here.
Attachment C is available here.
March 2001
The draft Hydrodynamic Model Calibration report was completed and
circulated to
MTRG members. The report may be reviewed here.
April 2001
An MTRG meeting was held on Tuesday, April 24, 2001(MTRG status report 4/24/01) in
Atlanta, GA
at the USEPA offices. The goals of the meeting were as follows:
May
2001
At the request of EPA, a
multi-agency
meeting of Federal agencies associated with the Savannah Harbor
Expansion
Project was held on 5/22/01 at the USFWS Wildlife Refuge office in
Savannah.
The agencies were represented by attendees from:
The
purpose was to discuss concerns that had surfaced in regard to the
H&S
model. (See MFR). The discussion ranged
over
concerns for the performance of the model to interactions with GPA and
ATM in
the development of the model and direct access to the model. The
agencies
decided to prepare precise and explicit criteria (a.k.a. goalposts),
which defined
what the model must provide in order to be used to assess potential
impacts. At
this point, it became clear that the Federal Agencies and GPA had very
different perspectives on what had been accomplished through the MTRG.
(See memo.)
June 2001
At the request of the Georgia Ports Authority (GPA), the Savannah
District
called an interagency meeting of the Federal Agencies associated with
the SHE
project and the GPA, their agents, and their contractors to discuss the
Federal
Agency views in regard to the subject model. The meeting was held on
Thursday,
28 June 2001 at the Environmental Protection Agency (EPA), Region IV. (Interagency Modeling Meeting 6/28/01).
The
agenda
for
that meeting was detailed and covered wide range of information that
GPA needed
to understand.
During the meeting, the draft
federal expectations document was presented to GPA and briefly
discussed.
The federal agencies requested that the field data collected in 1997
and 1999
be provided in the EPA's Water Resources Database (WRDB) format.
Discussion of access to the model was also held. Because of
intellectual
property rights and licensing agreements between ATM and ASA, it was
essential
to understand whether the agencies wanted the ability to change the
underlying
algorithms and code or just a "runtime" version that would allow
modification of the inputs and the ability to run the model. EPA,
USACE, and
USGS confirmed that their desire was for a runtime version.
In light of the formalizing of Federal agency interaction regarding the
H&S
and DO models, discussion was held about the effect this would have on
the MTRG
and the SEG. Another important aspect of discussion related to the
Memorandum
of Agreement, which was being developed between GPA and the USACE for
execution
of the Savannah Harbor Expansion Project. Since that was not finalized
at this
point, it was not clear who had which role and where authority lay for
project
decisions.
The USGS and EPA representatives agreed to introduce the newly
determined
federal agency participation in the calibration process and the
finalized
expectations document at the next MTRG meeting.
General
Reevaluation Study Modeling
(Top)
This period covers the time from the execution of the Memorandum of
Understanding between the USACE and the GPA in July 2001 to the
present.
September 2001
The Savannah District called an interagency meeting (Minutes - Federal Agency Coordination
Meeting 9/6/01)
of the Federal Agencies associated with the SHE project and the GPA,
their
agents, and their contractors to discuss the Federal Agency views in
regard to
the subject model. The meeting was held on Thursday, 6 September 2001
at the
Environmental Protection Agency (EPA), Region IV. The main goal of the
meeting
was to provide for discussion of the draft expectations document that
was
received at the June 2001 meeting with the federal agencies. In
addition, a
review of the turnover of field data in WRDB format and model turnover
were
discussed. Agreement was reached that the expectations document
contained goals
for achievement, rather than pass/fail criteria.
October 2001
The 1997 and 1999 field data sets were provided to the Federal agencies
in WRDB
format.
November 2001
An MTRG meeting was held on Thursday, November 8, 2001(MTRG status report 11/8/01) in
Atlanta, GA
at the EPA offices. The goals of the meeting were as follows:
The Federal agencies
involved in
the Savannah Harbor Expansion H&S and DO model calibration
discussed the
Federal agency coordination process and the draft agency expectations
document
with the MTRG.
The Federal agencies involved in the Savannah Harbor Expansion H&S
and DO
model calibration, now titled: "Savannah Multi-Agency Review Team
(SMART)", provided a document
detailing the process for finalization of the Savannah Harbor
H&S model
and a revised Federal expectations document.
February 2002
A meeting of the Federal agencies involved in the Savannah Harbor
Expansion
H&S and DO model calibration met with GPA representatives on
2/28/02 in
Atlanta. (SMART
meeting
minutes 2/28/02)
March 2002
The MTRG met on Mar 1, 2002 at the
EPA offices in Atlanta.. The goals of the meeting were:
The USACE, Savannah
District
provided the GPA
with a memorandum
detailing
the federal agency requirements for the contents and distribution of
the
H&S model review package.
April 2002
An MTRG meeting was held on Tuesday, April 30, 2002 in Atlanta, GA at
the EPA
offices. The goals of the meeting were as follows:
A SMART meeting was
held following
completion of the MTRG meeting. (SMART
meeting minutes 4/30/04). Discussion
included:
An initial H&S
model
acceptance package was issued by ATM to the SMART members.
(Top)
May 2002
Based on the feedback on the initial H&S model acceptance package
from the
SMART members in the 4/30/04 SMART meeting, a revision to the package
was
submitted by ATM. Included in Revision 1 to the acceptance package were:
June 2002
An MTRG meeting was held on Thursday June 6, 2002 in
Atlanta, GA
at the EPA offices. The meeting included discussion of:
A SMART meeting was
held following
the MTRG meeting on June 6, 2002. (SMART meeting summary 6/6/02)
Discussion included:
EPA stated the model
was
sufficiently calibrated to proceed to D.O. modeling and would defer to
the
USFWS on utility of the model (salinity and water levels) to address
impacts to
the marshes. ATM agreed to provide a revised approval package that
acknowledged
the need for additional processing to provide usable input for
evaluation of
wetland impacts.
July 2002
A memorandum
detailing the revised process for calibration and review for the
H&S,
DO, Cl, and Marsh Succession Models was provided by the SMART to the
GPA. This
established the sequence of events leading to the acceptance of the
H&S
model. Those events were:
August 2002
A final H&S
model
acceptance package was issued to the SMART members for review. This
acceptance package was issued in lieu of a calibration report in an
effort to
reach a decision on the H&S model calibration so that work on the
DO model
could proceed. The plan was to provide a calibration report after the
DO model
calibration was accepted.
(Top)
September 2002
An MTRG meeting was held on Tuesday, September 18, 2002 in
Atlanta, GA
at the EPA offices. The meeting included discussion of:
Based on their review
of the
H&S model acceptance package, the federal agencies each accepted
the model
for use in the project and as a basis for further development and
calibration
of the DO model.
EPA letter
Department
of Interior
letter
Department
of Commerce
letter
USACE letter
November 2002
At the request of EPA, a meeting was held to discuss how to
proceed
with the final phase of the DO modeling effort "...so that the
calibration
will be accomplished in an efficient and appropriate time frame to the
satisfaction of the Federal Agencies." A memorandum describing
the agreements reached was provided to the Savannah District from the
meeting
participants.
December 2002
Dr. Johnson, USACE Engineering Research and Development Center (ERDC)
offered recommendations
for possible improvements based on the August 2002 acceptance
package.
March 2003
ATM provided responses
to Dr. Johnson's suggestions after investigating each. Their
recommendations were that no modification be done to the calibration.
Based on
testing that showed only marginal improvement in some of the variants
tested,
there was not enough improvement overall to warrant additional work.
May 2003
A data characterization report
dealing
with the 1999 dataset was issued by ATM. The SMART met on May 16, 2003
to
discuss DO model calibration, review the data characterization report
and
discuss the base case for the modeling. The meeting report is here.
July 2003
A complete draft DO model calibration report
was
issued by ATM to the SMART.
August 2003
The Savannah District provided comments
received
from the SMART members regarding the complete draft DO model
calibration
report.
Questions raised about vertical mixing were responded to by ATM by way
of
explanation of their choice of vertical mixing methodology. (Memo
dated
19Aug 03) This was the first discussion of the vertical mixing
formulation chosen
by ATM
in 1998 since the MTRG discussions of the March 2001 Draft H&S
model calibration report. Prior to this point, the focus of the
modelers and reviewers
had been exclusively
on model performance - how well it met the expectations goals.
On 20 August 2003, a meeting of
representatives from the Savannah Harbor Expansion Project and the
Savannah Harbor Ecosystem Restoration Project met to discuss the review
of the draft DO model calibration
report. Feedback that was given was incorporated into the planning for
production of the final calibration reports for both the H&S and DO
models.
(MFR
dated 3 Sep 03).
September 2003
Additional comments
were forwarded by the Savannah District that resulted from the
Water
Quality Joint Agency Meeting. This letter emphasized the need for the
calibration reports on both models to address defensibility:
"Agencies
are looking for calibration report that presents the defensibility of
the model
in all aspects (application, calibration, and prediction) for
evaluation of the
deepening impacts."
(Top)
December 2003
The Savannah District provided details
of
how the federal agencies would review and evaluate the calibration of
the
H&S and DO models.
January 2004
The final H&S and DO model calibration report
was
delivered to the federal agencies in hard copy and CD-ROM format.
Included with
the report was the latest version of the model for agency use.
March 2004
The SMART held a meeting on Mar 3, 2004 in response to a request from GPA.
The purpose was for SMART members to formulate a written request for
clarification of any
questions or
concerns they had, so
that they could be addressed formally by ATM. The federal agencies wanted to be able to
discuss their opinions amongst themselves, so GPA was not present at
the meeting.During the
meeting objections were
voiced
about the defensibility of the models as predictive tools. The summary
report of the meeting is available here.
Based on the results of
discussions between ATM and agency modelers after the meeting, it
appeared that the conclusions were founded, in
part, on
misinterpretations of the contents of the calibration report. A
memorandum from ATM describing their
understanding of the misunderstandings is available here.
GPA requested a meeting with the SMART members to discuss their
conclusions
with the ATM modelers present and able to respond to the feedback from
the
SMART members. That meeting was held on Mar 31, 2004. In preparation
for the
meeting, GPA requested each agency provide written comments regarding
their
concerns with the vertical mixing scheme only, since that was a key
decision
point for the agencies. If the vertical mixing methodology was not
acceptable
and the models were not predictive tools, they could not be used. ATM
provided
written responses to those concerns - see part 1
and part
2. The outcome of the meeting was that the SMART members judged
that the models, as configured, were
not defensible by their resepective agencies.
April 2004
On April 7, 2004, the regional heads of the lead and cooperating
agencies met
in an Executive Management Group session. At that meeting, GPA was
presented
with the official agency positions on the models calibration, which are
listed
below:
The Executive
Management Group
agreed to examine alternatives for the way forward in modeling and meet
to
discuss them in mid May 2004. The report of the April meeting is here.
A meeting of the Savannah Harbor Water Quality Working Group was held
on April
22, 2004 to review the status of EPA's efforts to develop the Plan B DO
model.
(Note: This group was constituted by EPA to deal with TMDL setting and
is not a
part of the Savannah Harbor Expansion project.) The Savannah
District
requested a letter from each agency expressing their position on the
Plan B
H&S model (EFDC) by the end of April. EPA's goals for the TMDL
analysis and
the setting of a D.O. Water Quality standard for the State of Georgia
were
discussed along with the Corps need to develop or select and apply
models to
identify expected impacts from the Savannah Harbor Expansion Project.
It was
agreed that EPA would take the lead on issues concerning TMDL
development and
technical development of the EFDC models while the Corps would take the
lead on
issues concerning the application of the models to evaluate harbor
deepening.
Grid resolution, boundary conditions, and loadings were also discussed.
Details
are available here.
(Top)
May 2004
On May 3, 2004, GPA hosted a
meeting
of SEG members interested in the status of model calibration for the
project.
The meeting was held in response to a request from the SEG. Meeting
minutes
were not formally kept, nor was a list of attendees generated.
Attendees
included SEG members, agency representatives, technical representatives
(modelers) from agencies and ATM, along with project management
representatives. Two purposes were identified for the meeting:
After a review of the
modeling
effort for the Savannah Harbor Expansion project, much of the
discussion
centered on questions from the SEG members. Emerging from the
discussion was
the following feedback:
GPA promised to take
the
suggestions and discussion from the meeting to the federal agencies for
consideration. In a letter to
each of the Federal agencies represented in the EMG, GPA expressed
their opinions and recommendations about the Savannah Harbor Expansion
Project modeling.
On May 21, 2004, the
Executive Management Group met at GPA
headquarters.
The purpose of the meeting was to decide the path forward regarding
modeling.
The federal agencies decided that further development of the Plan A
models was
not warranted since they judged them to not be defensible. The
available
resources were to be shifted to the development of the Plan B (EFDC and
WASP) models.
When the
EFDC and WASP models were calibrated for use by the Savannah Harbor
Expansion Project, their suitability would be judged based on the
performance
expectations
established for the project during Plan A development. The meeting
report for
the meeting is available here.
The decision memorandum is available here and
the accompanying information paper here.
The federal agencies generated a consolidated response to GPA's letter
from May 11, 2004, which can be reviewed here.
(Top)
August 2004
Following the Executive Management Group meeting on May 21,
2004, the
Savannah District and GPA reviewed what had transpired in the Plan A
modeling
efforts. This led to the identification of important considerations to
be
incorporated into the calibration of the EFDC and WASP models (Plan B)
for use.
Those considerations are available here.
May
2005
Refinement of the EFDC and WASP models was contracted by the
USACE, Savannah District to Tetra Tech, Inc. The status of their work
can be viewed here.
Future information will be
posted to the model information page located here.