Archive for Mardi Gras Pass
This was originally posted by Environmental Defense Fund on EDF Voices.
By Estelle Robichaux, Restoration Project Analyst, Environmental Defense Fund
Soon after my flyover of the Mississippi River Delta, I joined Dr. John Lopez of the Lake Pontchartrain Basin Foundation (LPBF) on a boat ride down the Bohemia Spillway to Mardi Gras Pass. As we sped down the spillway canal, beautiful swamp lilies and purple morning glories popped out against a backdrop of lush, green plants. Once we reached our destination, we saw an incredible number of birds: Laughing Gulls, Snowy Egrets, Great Blue and Tricolored Herons – just to name a few. This, along with an increase in the number of river otters and beavers observed, is a good indicator that there are healthy fish populations in the area.
Thirty-five miles southeast of New Orleans, Mardi Gras Pass is the Mississippi River’s newest and naturally evolving “distributary,” a channel of water that flows away from the main branch of the river. This new distributary began forming during the spring flood of 2011, when the water level of the Mississippi River was so high that it flowed over the natural levee in this area. When the floodwaters receded, Dr. Lopez and his team of scientists noticed two breaches in the embankment. These breaches continued to widen and deepen and soon, right around Mardi Gras Day 2012, the breach was complete. The Mississippi River was once again connected to the surrounding wetlands, allowing freshwater and land-building sediment back into the area.
Louisiana has lost 25% of its coastal land area since 1930 and continues to lose land at an alarming rate – one football field every hour, on average. Man-made levees along the Mississippi River cut off many small distributaries, like Mardi Gras Pass, from the wetlands in the floodplain of the river and have contributed to this massive wetland loss. Our team here at EDF works with partner organizations, including the Lake Pontchartrain Basin Foundation, as part of the Mississippi River Delta Restoration Coalition, which has a vision of reconnecting the Mississippi River to its delta to help protect people, wildlife and jobs in coastal Louisiana.
To address the complex, yet urgent need for coastal restoration in Louisiana, the state legislature unanimously passed the 2012 Coastal Master Plan. This plan is a long-term, science-based restoration program that includes nearly 250 restoration projects such as barrier island restoration, marsh creation, establishment of oyster barrier reefs and sediment diversions that will help rebuild Louisiana’s disappearing coast.
Restoring our coast, restoring my hope
One of the principal guidelines for restoration under the Coastal Master Plan is to address the root causes of land loss by using the natural power of the Mississippi River to build land at a large scale. Sediment diversions, a central component of the plan, embody this principle because they are designed to mimic the natural stages of the river and carry sediment to the areas of coastal Louisiana that need it most. By operating diversions at times of high water flow (like during a flood), large amounts of sediment can be diverted. It will then settle out in the wetlands and shallow bays, eventually building land mass in vulnerable coastal areas.
In a way, Mardi Gras Pass is a naturally occurring ‘pilot project’ of a sediment diversion. Knowledge gained from studying this area can tell us about the land-building properties, as well as the short-term effects, of sediment diversions. To learn more about this, LPBF scientists are studying how the reintroduction of freshwater and sediment to the spillway area is changing the wetlands and affecting wildlife populations.
Swift currents and downed trees along the edge of the flooded forest can make navigating Mardi Gras Pass somewhat treacherous, but we, in a trusty 14’ skiff, maneuvered through the channel and onto the Mississippi River for a brief but thrilling cruise.
This is what it means for the river to be connected to its floodplain, I thought as we emerged out onto the open water, this is what this ecosystem is supposed to be like.
Although I grew up only a few miles from it, this was the third time in my life I had been out on the Mississippi River and the first time it was in a boat small enough that I could reach down and touch its muddy waters. As our tiny boat circled out in that mighty river, despite the heat and the midday sun, I had goose bumps.No Comments
Basics of the Basin research symposium discusses past, present and future of the Pontchartrain BasinNovember 6, 2013 | Posted by Delta Dispatches in Mardi Gras Pass, Meetings/Events, Mississippi River Gulf Outlet, Science
By Shannon Hood and Estelle S. Robichaux, Environmental Defense Fund
On October 24-25, 2013, the Lake Pontchartrain Basin Foundation (LPBF) hosted its 11th Basics of the Basin research symposium. Scientists and researchers from academia, non-profit organizations, private consulting groups and federal and state agencies gathered at the University of New Orleans (UNO) on the shores of Lake Pontchartrain to discuss the past, present and future issues of the Pontchartrain Basin. LPBF has hosted these biennial symposiums since 1992, providing an opportunity for students and established researchers alike to share and discuss the most up-to-date research on the restoration and management of Louisiana’s Pontchartrain Basin.
After opening remarks by Dr. John Lopez, executive director of LPBF, the plenary continued with comments and presentations from Phil Turnipseed of the U.S. Geological Survey; Dr. Ioannis Georgiou, Director of the Pontchartrain Institute for Environmental Sciences at UNO; and Dr. Chip Groat, President and CEO of The Water Institute of the Gulf, among others. The conference was grouped into seven general session topics, including hydrodynamic modeling, water quality, storm surge protection, river diversions, wetland restoration, the Central Wetlands Unit and fisheries. Because of the diversity of environmental concerns within the Pontchartrain Basin, broad, interdisciplinary research is essential to effective system-wide restoration and management.
Understanding the present condition of the Lake Pontchartrain Basin requires a look into the history of the lake itself. Dr. Oliver Houck, professor at the Tulane University Law School, provided the storied account of the history of Lake Pontchartrain during his keynote speech. He spoke of the lake’s days as a hot spot for recreation, as well as its decline during the years when the lake was dredged for the clam shells that lined the bottom. This dredging caused a rapid decline in the health and suitability of this lake for wildlife habitat and for recreation. A few brave souls recognized the trauma that the lake was enduring and took on the task of halting the dredging to allow the lake to begin to heal. Through years of dedication, lawsuits and creative thinking, the dredging was successfully stopped, and the healing process began.
Lake Pontchartrain Basin Foundation’s original research was well represented at the conference, with 14 presentations in six different sessions. Eva Hillman presented LBPF’s research into the salinity levels found within wetland soils in the Central Wetlands Unit (CWU), just west of New Orleans. Construction of the nearby Mississippi River Gulf Outlet (MRGO) in 1968 allowed salt water to easily enter these previously freshwater wetlands and lead to severe deterioration of the CWU wetlands. Although the MRGO has been closed since 2009, much of the area still remains highly degraded. LPBF scientists are monitoring soil salinity throughout the CWU to inform restoration efforts, specifically re-vegetation projects.
Research conducted by LPBF scientists on Mardi Gras Pass, a new and evolving distributary of the Mississippi River, was also on display. Dr. Theryn Henkel presented preliminary research on where the fresh water and sediment from Mardi Gras Pass is going once it enters the receiving basin. Results from this study indicate that the deposition of sediment happens well before the influence of fresh water on salinity levels in the receiving basin is no longer observed, and that sediment travels further into the northern areas of the basin than it does to the south. Andreas Moshogianis presented the preliminary findings of ongoing biological assessments in Mardi Gras Pass, most notably that a range of both fresh- and saltwater fishes have been caught during these assessments, often in the same net. LPBF’s research on Mardi Gras Pass is important because it has implications for future restoration efforts throughout coastal Louisiana, as scientists and citizens work to reconnect the Mississippi River with its delta.No Comments
By Emily Guidry Schatzel, Communications Manager, National Wildlife Federation
Recent news reports suggest that the potential for compromise exists in the case of Mardi Gras Pass, the newest known distributary of the Mississippi River. The pass was discovered in 2012 when the river cut a channel through its bank in the Bohemia Spillway, a stretch without levees, giving an exciting and rare view at how a natural delta system operates.
While the pass promises ecological prosperity for the delta, the newly enlarged channel washed out the private road that one local oil company uses to access its facilities. The company has since applied for a permit to rebuild that road. Coastal restoration advocates believe that the current plan to rebuild will effectively close the Mardi Gras Pass and will eliminate encouraging ecological benefits that scientists from the Lake Pontchartrain Basin Foundation have been monitoring since the channel’s development.
This video further explains the debate over keeping the pass open, and alternatives for compromise. The key takeaway? Whether it be construction of a bridge, or another reasonable alternative that gives the oil company access while allowing Mother Nature to literally “run its course,” this is clearly an issue that requires the full attention of key decision-makers so that the best long-term solution is achieved.
As Dr. John Lopez, executive director of the Lake Pontchartrain Basin Foundation — the organization that discovered the pass in 2012 — said, “It’s the kind of thing that most scientists sit in their offices there, dreaming how it might happen. Here, you can actually see it.” Keeping Mardi Gras Pass open is important — it’s a chance for the river to reconnect with its wetlands, which is exactly what the river is designed to do.1 Comment
At just five months old, Mardi Gras Pass is the newest distributary of the Mississippi River — a modern addition to an ancient system. Located about 50 miles south of New Orleans on the east bank of the river, the pass was discovered by Lake Pontchartrain Basin Foundation (LPBF) staff on Mardi Gras Day 2012. The natural flow of the Mississippi River had cut a continuous channel through the river’s bank and into the Bohemia Spillway, creating a new distributary and offering a small glimpse at what a natural delta system looks like.
On August 1, Louisiana’s Governor’s Coastal Advisory Commission held their regular meeting in Davant in Plaquemines Parish. At the meeting, Dr. John Lopez, executive director and coastal sustainability program director for LPBF, presented on the status of Mardi Gras Pass to the commission. The presentation showcased how LPBF and its partners were taking every advantage to study and learn about the river’s natural ability to connect to the wetlands. In June, LPBF released a report on the dimensions of the new channel, and its staff continues to regularly monitor the pass’s progress. Both the report and Dr. Lopez’s presentation can be found at SaveOurLake.org.
Mardi Gras Pass’s flow has increased modestly since February, but the discharge is almost entirely dependent on the height of the Mississippi River water level. This summer, while the river has been exceptionally low, the flow rate has been less than 500 cubic feet per second. But when the river rises toward the end of the year, the flow could be ten times greater.
The Governor’s Commission also visited Bohemia Spillway and Mardi Gras Pass themselves. They were taken to a location where the newly-established Mardi Gras Pass has cut through a private road within the spillway, making it impassable. A local oil company has applied for a permit to repair the road, which could close off the flow from the river and block the pass. The state has expressed scientific interest in Mardi Gras Pass and recognizes it as a potential restoration opportunity. Therefore, the state has requested that the company evaluate alternatives to repairing the road which would allow the pass to still function.
The Commission also visited the actual location where Mardi Gras Pass has cut through the Mississippi River’s bank. Some Commission members had never seen the Mississippi River without an artificial river levee, and it was a moving experience to see the river in its natural condition and to see the meandering Mardi Gras Pass’s channel cutting through the river’s willow tree forested bank. Mardi Gras Pass is a real-life example of nature at work. As a natural distributary and natural diversion, Mardi Gras Pass represents a small precursor to what a more natural Mississippi River and delta could look like in a Coastal Master Plan future.
- Presentation to Governor's Commission: Status of Mardi Gras Pass, the Newest Distributary Pass of the Mississippi River within the Bohemia Spillway, Southeast Louisiana (Lake Pontchartrain Basin Foundation)