LCA Mississippi River
Hydrodynamic and
Delta Management
Study (MRHDMS)
Carol Parsons Richards
River Studies Manager
Governor’s Advisory Commission on Coastal Protection,
Restoration, and Conservation
June 6, 2013
committed to our coast
committed to our coast
Background and Authorization
• The MRHDM study is comprised of two large-scale
initiatives for the Mississippi River that were outlined in
the 2004 LCA report:
• Mississippi River Hydrodynamic Study
• Mississippi River Delta Management Study
• The study is authorized under Section 7003 of the Water
Resources Development Act (WRDA) 2007 (Public Law
110-114).
Coastal Protection and Restoration Authority of Louisiana
Project Area
LCA Mississippi River Hydrodynamic
and Delta Management Study Goal
•
Reconnect Mississippi River water, sediment, and
nutrient resources to the surrounding basins sufficient
to provide a sustainable coastal ecosystem that allows
for the coexistence of navigation and flood risk
reduction.
Coastal Protection and Restoration Authority of Louisiana
LCA MRHDMS Team
Biedenharn Group, LLC
Over 30 Federal, State, Academic,
and Private Scientists and Engineers
Hydrodynamic Study
Study Manager: Carol Parsons Richards
Hydrodynamic Study Objectives
• Identify Mississippi River resource quantities and
locations that can be effectively directed to support long
term sustainable restoration in balance with multiple
river and basin functions.
• Provide a decision making framework (e.g., models, etc.)
and criteria for making programmatic management
decisions of managing sediment and water for
restoration.
Coastal Protection and Restoration Authority of Louisiana
Hydrodynamic Study Tasks
• Geomorphic analysis
• Data collection and management
• Development of one dimensional (1D) hydrodynamic
model of the Mississippi River
• Development of multi-dimensional hydrodynamic
models
• Modeling metrics
• Expanded small scale physical model production runs
Coastal Protection and Restoration Authority of Louisiana
Geomorphic Analysis
Purpose
• Integrates existing field surveys, gage data, sediment
data, hydraulic data, hydrologic trends, and natural and
anthropogenic changes to characterize process-form
interactions of the river, identify control points and
problem locations, and support division of the system
into distinct reaches or areas that may be individually
classified with respect to morphology.
Status
• Draft report due in June 2013.
Coastal Protection and Restoration Authority of Louisiana
Data Collection and Management
Purpose
• Collect bathymetry, bed morphology changes, bed load
flux of sediment, sand sheet thickness, three-dimensional
flow dynamics, water velocities, discharge, suspended
load flux load, grain size distribution, salinity,
temperature, turbidity, nutrient data.
• These data are critical to the development and
refinement of one dimensional and multi-dimensional
models that will simulate the complex behavior of water,
sediment, nutrients, and salinity.
Status
• Data were collected in 2011 and 2012, and will continue
in 2013.
Coastal Protection and Restoration Authority of Louisiana
One-dimensional Hydrodynamic Model
Purpose
• Evaluate long-term (years to decades) responses of the
Lower Mississippi River to operation of existing and
proposed diversions.
• Estimates longitudinal (reach-scale) variations in
sediment delivery, scour and deposition, and bed
material gradation.
Status
• Future without project (FWOP) conditions simulations
completed for sea level rise scenarios, draft report due
June 2013. Working on first project production run,
sediment diversion in the vicinity of Myrtle Grove.
Coastal Protection and Restoration Authority of Louisiana
Multi-dimensional Hydrodynamic
Models
Purpose
• Develop multi-dimensional modeling tools (ADH-SedLib,
Delft 3D, FVCOM, Flow 3D) that will be used to simulate
the hydrodynamic and transport processes and
pathways that govern the behavior of the lower
Mississippi River, including transport of salinity,
temperature, and sediment.
Status
• FWOP analyses for all models scheduled in Summer
2013.
Coastal Protection and Restoration Authority of Louisiana
Modeling Metrics
Purpose
• Develop metrics to assess the predictive performance of
the numerical models
• Ensure transparency in the models performance
evaluation and provide objective, quantifiable measures
for evaluating the models performance
• Provides uncertainty bounds on the model results
allowing disclosure of risks, associated assumptions and
uncertainties related to model performance
Status
• The metrics report was completed March 2013. The
metrics are currently being applied to the models before
production runs are completed.
Coastal Protection and Restoration Authority of Louisiana
Expanded Small Scale Physical
Model Production Runs
Purpose
• Used as supplementary information in the screening of
the final array of alternatives to reach the tentatively
selected plan
• Intended for visualization, educational public outreach
purposes, and for supplementary analysis
Status
• New model construction completion is estimated for
December 2014.
• Production runs will be funded through MRHDMS, not
model construction.
Coastal Protection and Restoration Authority of Louisiana
Hydrodynamic Study: Next Steps
• Geomorphic analysis:
Final report Summer 2013
• Data collection and management:
Ongoing in 2013, data collection dependent on river
conditions
• 1D hydrodynamic model:
Project modeling production runs complete by
December 2013
• Multi-dimensional hydrodynamic models:
FWOP and project modeling production runs
complete by December 2013
• Modeling Metrics:
Apply metrics to the models
Coastal Protection and Restoration Authority of Louisiana
Delta Management Study
Study Manager: Renee Bennett
Delta Management Study Objectives(1)
• In areas surrounding coastal communities, achieve a
sustainable net positive elevation change relative to sea
level rise and subsidence by adjusting bayside hydrology
and re-establishing geomorphic connectivity of the
Mississippi River to the receiving basins to introduce and
retain sufficient volumes of sediment, freshwater, and
nutrients.
Coastal Protection and Restoration Authority of Louisiana
Delta Management Study Objectives(2)
• Formulate alternatives that:
• Consider multi-use and multi-purpose projects that
involve ecosystem restoration, flood risk management,
and navigation.
• Alternatives will be heavily guided by the 2012
State Master Plan.
• Arrive at a long term multi-purpose project that is
sustainable and meets the needs of the Nation.
• Could mean changing currently authorized project
purposes to arrive at a multipurpose plan that
appropriately balances ecosystem, navigation, and
flood risk management needs and purposes.
Coastal Protection and Restoration Authority of Louisiana
Delta Management Study Tasks
• Compilation of existing information
• Document existing conditions
• Forecast future conditions
• Utilize model developed under Hydrodynamic Study
to document future conditions
• Develop ecological models to document impacts to
biological resources
• Complete NEPA documentation
• Public outreach/Stakeholder engagement
Coastal Protection and Restoration Authority of Louisiana
Delta Management: Activities to Date
• August 2011- Project Management Plan and Cost Share
Agreement signed
• February-March 2012- USACE SMART Planning Guidance
Issued (3x3x3)
• October 2012- MRHDMS Planning Guidance Charette
Status:
• Awaiting guidance from USACE on Planning Guidance
Waiver
Coastal Protection and Restoration Authority of Louisiana
Delta Management: Next Steps
If waiver is granted:
• Renegotiate the PMP while the team begins developing
measures and an initial array of alternatives.
• Finalize the tools to be used to screen alternatives and for
documentation of impacts.
• Public outreach activities will increase.
• Chief’s Report is expected to take 3.5 years and is
anticipated to be completed Summer/Fall 2016.
Coastal Protection and Restoration Authority of Louisiana
Questions?
Carol Parsons Richards
Carol.Richards@la.gov
225-342-9430
Coastal Protection and Restoration Authority of Louisiana