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 Authorizatio n

• 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

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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.

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Status

Draft report due in June 2013.

Coastal Protection and Restoration Authority of Louisiana

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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

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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

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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

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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

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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

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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 [email protected]

225-342-9430

Coastal Protection and Restoration Authority of Louisiana