Simulating Hurricane Storm Surge in the Lower Mississippi River under Varying Flow Conditions

This paper reports a reconnaissance level study of a storm surge barrier in the Mississippi River. Historical hurricanes have shown storm surge of several meters along the Mississippi River levees up to and upstream of New Orleans. Future changes due to sea level rise and subsidence will further increase the risk of flooding due to hurricane storm surge. A surge barrier downstream of New Orleans has been considered as an alternative to levee raise along the Mississippi River. Hydraulic computations show that the build-up of water behind the barrier due to the Mississippi River flow is (much) lower than the hurricane surge protruding up the river in the no-barrier situation. The barrier will probably eliminate the need to upgrade the system upstream of the barrier while providing the same level of hurricane risk reduction. A hybrid barrier (a combination of different gate types) with a primary swing gate for navigation (and flow) and secondary lift gates to accommodate for flow is a technically feasible alternative. The barrier remains open for almost the entire year and would only to be closed during severe tropical events (say once every 2 - 3 years). Several measures are included in the conceptual design to mitigate the navigation impact. The construction costs of the barrier are estimated at $1.6 - 2.6 billion. It is recommended to compare the investment costs of a barrier including adjacent tie-ins to the existing HSDRRS to the costs of upgrading and maintaining the levee system throughout the city of New Orleans.

Download Full-text

Once-Through Cooling Potential of the Middle and Lower Mississippi River During Low Flow Conditions

Journal of Engineering for Power ◽

10.1115/1.3230773 ◽

1981 ◽

Vol 103 (3) ◽

pp. 594-601

Author(s):

A. R. Giaquinta

Keyword(s):

Mississippi River ◽

Power Plants ◽

Low Flow ◽

Flow Conditions ◽

Consumptive Water Use ◽

Temperature Distributions ◽

Longitudinal Temperature ◽

Lower Mississippi River ◽

Consumptive Water ◽

Plant Capacity

The once-through cooling potential of the Middle and Lower Mississippi River has been computed for the seven-day, ten-year low flow by the steady-state Iowa Thermal Regime Model. Longitudinal temperature distributions are shown with existing power plants and future power plants proposed through 1995. Permissible future plant additions based on current thermal standards also are determined. It is shown that even if thermal standards were based on low flow conditions, no existing or proposed future power plants will violate present thermal standards, and the total permissible future fossil-fueled power plant capacity along the study reach ranges from about 70,000 to 90,000 MW depending on the temperature base used. It also is shown that the total consumptive water use for existing and proposed future plants should cause no problems even during periods of low flow.

Download Full-text

MODELING THE EFFECT OF LAND-BUILDING PROJECTS ON STORM SURGE AND HURRICANE WAVES IN COASTAL LOUISIANA

Coastal Engineering Proceedings ◽

10.9753/icce.v36.risk.21 ◽

2018 ◽

pp. 21

Author(s):

Kelin Hu ◽

Qin Chen ◽

Ehab Meselhe

Keyword(s):

Storm Surge ◽

Mississippi River ◽

Coastal Wetlands ◽

Wetland Loss ◽

High Rate ◽

Coastal Protection ◽

Building Projects ◽

Lower Mississippi River ◽

Louisiana Coast ◽

Coastal Louisiana

Wetland loss on the hurricane-prone Louisiana coast continues at an alarmingly high rate. Coastal Louisiana is at risk of losing between 2118 and 4677 km2 of land over the next 50 years (Couvillion et al., 2013). To combat the devastating wetland loss, the Louisiana 2017 Coastal Master Plan (CMP) called for sediment diversions along the lower Mississippi River to enhance sediment supplies to coastal wetlands and build more wetlands. The Louisiana Coastal Protection and Restoration Authority (CPRA) plans to spend $2 billion on the Mid-Breton and Mid-Barataria sediment diversion projects. In this study, numerical experiments were conducted to quantify the effect of land-building projects on storm surge and hurricane waves in Barataria and Breton Basins of Louisiana.

Download Full-text