CPRA recommends advancing two Mississippi River sediment diversions

Baton Rouge, La. — The Louisiana Coastal Protection and Restoration Authority (CPRA) made a recommendation to advance both the Mid Barataria (75,000 cfs) and Mid Breton (35,000 cfs) sediment diversions to engineering and design. This recommendation is based, in part, on recent results of a suite of diversion studies initiated in late 2013 in response to concerns raised by various stakeholder groups. The announcement comes several months in advance of a formal request for the additional funds needed for engineering and design. The funding request will be included in the CPRA’s Annual Plan, which will go before the CPRA Board and the Louisiana Legislature in early 2016.

“Decades of studies have suggested the importance of diversions,” said CPRA Board Chairman Chip Kline. “The analysis conducted as part of the 2012 Coastal Master Plan further indicated that sediment diversions are essential to sustaining coastal Louisiana. With predictable funding becoming available as a result of the oil spill settlement, we have the opportunity to invest in systemic restoration tools like diversions, which mimic natural processes by reconnecting the river to the delta. In doing so, we anticipate extending the longevity of many of the more substantial marsh creation projects called for in the master plan. As we transition to these larger projects, the Board recognizes that this work will become increasingly more difficult. That is exactly why we approved the request for funds to conduct these studies and why we continue to utilize this forum to engage resource agencies, stakeholder groups and members of the public in these difficult but necessary discussions.”

In late 2013 the CPRA Board approved the use of approximately $13 million to advance a suite of studies related to the lower Mississippi River sediment diversions proposed in the 2012 Coastal Master Plan. The goal of those studies was two-fold: to address concerns raised by various stakeholders and to allow the CPRA to better understand benefits and limitations of the proposed projects. The funds utilized to conduct the studies were made available through criminal settlements associated with the Deepwater Horizon oil spill. The settlements included approximately $1.27 billion to be directed to the National Fish and Wildlife Foundation (NFWF) specifically dedicated for barrier island and diversion projects in Louisiana.

“As these studies have matured and the results are coming in, we’re continuing to have confidence in the ability of sediment diversions to maximize our use of riverine resources to create a more sustainable footprint for coastal Louisiana,” said CPRA Executive Director Kyle Graham. “It became evident through our preliminary analysis that the Mid Barataria and Mid Breton diversions should be prioritized to advance into engineering and design. While this recommendation is a very important step we still have much work to do prior to implementation. We anticipate the engineering and design work will take several years. During that time we will further refine our analysis, develop an operational regime and continue to engage the public as we progress through the design and permitting process.”

The studies utilized some of the most advanced modeling tools available, such as Delft 3-D, CASM and EwE to predict changes that could potentially occur as a result of implementing sediment diversions. A complementary effort using outputs from these models is underway to investigate and understand potential socioeconomic impacts. In evaluating the modeling results, the CPRA is considering a number of factors including the projects’ ability to build or maintain land, effects on the river, changes in water levels, changes to salinity, habitat diversity and quality, abundance and distribution of fisheries and economic trends. In addition to analyzing modeling results, the CPRA is also considering project costs, funding availability and continued feedback from stakeholders.

Throughout the next several months, the CPRA will conduct approximately 20 key briefings to discuss these results in further detail with various stakeholder groups.