Mississippi River Gulf of Mexico Watershed Nutrient Task Force Gulf Hypoxia Action Plan 2008 Sediment loads from the Mississippi and Atchafalaya Rivers empty into the Gulf of Mexico. 1 Contents Moving Forward on Gulf Hypoxia 2 Framework for Action. 8 n Principles ..................................................................... 8 n Goals ......................................................................... 9 n Critical Needs ............................................................... 10 Progress and Reassessment 2001–2007. 14 n Trends in the Size of the Hypoxic Zone ........................................ 14 n Trends in Nitrogen and Phosphorus in the Basin .............................. 15 n Progress on Actions in the 2001 Action Plan ................................... 17 n Updating the Science ........................................................ .20 n Conclusions from the Reassessment .......................................... 21 Next Steps: Getting Results 28 Actions to Accelerate the Reduction of Nitrogen and Phosphorus. 29 Actions to Advance the Science, Track Progress and Raise Awareness. 42 Appendix 60 Mississippi River/Gulf of Mexico Watershed Nutrient Task Force . Gulf Hypoxia Action Plan 2008 Moving Forward on Gulf Hypoxia 2 Moving Forward ore than thirty years after the passage and includes waters from several major river Mof the Clean Water Act, a large area systems, including the Missouri/Platte River of low oxygen or hypoxia, absent of most Basin, the Ohio/Tennessee River Basin, and the marine life and threatening to inexorably Arkansas/Red/White River Basin. The Mississippi change the biology of the region, continues River Basin includes two functionally distinct to form in the Gulf of Mexico during periods zones, each with its own potential to contribute in the summer off the coasts of Louisiana to the reduction of Gulf hypoxia. These zones and Texas. The hypoxia is primarily caused include the huge Mississippi watershed with by excess nutrients—originating from the its tributary network, and at the lower end of great productivity of Middle American cities, the river system, the deltaic zone that formerly farms, and industries—which cause extensive dispersed river water naturally throughout growths of algae that deplete the oxygen in Southeast Louisiana via a distributary (deltaic) the water when they die, sink to the bottom, network. While the tributaries of the Mississippi and decompose. The condition is exacerbated River are the sources of nutrient loading to by the stratification of the water column— the river trunk, the distributaries within the the result of warmer, low salinity surface Mississippi Delta are critical to the final dispersal waters that isolate the organic-rich bottom of nutrients and sediments into the Gulf of waters from the surface and prevent oxygen Mexico and the salinity of the estuaries and exchange with the atmosphere—which coastal waters. occurs where the Mississippi River meets the Gulf of Mexico. The distributary zone includes the entire area influenced by river flow south of the Old River The watershed of the Mississippi River drains Control Structures, where the Atchafalaya River 41 percent of the contiguous United States diverges from the lower Mississippi River and Mississippi River/Gulf of Mexico Watershed Nutrient Task Force . Gulf Hypoxia Action Plan 2008 Moving Forward on Gulf Hypoxia 3 on Gulf Hypoxia the Red River merges with the Atchafalaya (Figure 1). During the past two centuries the hydrology of the distributary zone was totally modified by the construction of flood levees and closing of key distributaries for flood control and navigation enhancement programs. These structures isolated the river from its delta, causing an ongoing catastrophic collapse in the deltaic landscape, primarily wetlands. The hydrologic changes that have caused such damage to South Louisiana also exacerbate Gulf hypoxia by jetting most nutrient-rich river water and sediments directly into the Gulf of Mexico, bypassing the deltaic wetlands that require the nutrients and sediments. Figure 1. Deltaic plain of Louisiana showing land built, maintained, and nourished over States and Tribes within the entire Mississippi/ thousands of years by many distributary Atchafalaya River Basin and Federal agencies channels of the Mississippi River, including the two that are currently active. are working together to take action to reduce the size of the hypoxic zone, while protecting and restoring the human and natural resources of the Mississippi River Basin. In January 2001, the Mississippi River/Gulf of Mexico Watershed Mississippi River/Gulf of Mexico Watershed Nutrient Task Force . Gulf Hypoxia Action Plan 2008 Moving Forward on Gulf Hypoxia 4 Nutrient Task Force issued the Action Plan for Six major policy themes provided direction Reducing, Mitigating, and Controlling Hypoxia for the reassessment. These themes address in the Northern Gulf of Mexico. The plan was needed improvements to the 2001 Action Plan submitted in accordance with the Harmful within the adaptive management framework Algal Bloom and Hypoxia Research Control and include: Act of 1998. The plan stimulated a great deal of collaboration in understanding science and 1. Acknowledge the social, political and planning; however, much work remains to be economic changes and links to emerging done to implement it. issues and policies. The vast drainage basin of the Mississippi/Atchafalaya River Basin and The Task Force has updated the initial plan the adaptive management framework of the through a multiple-step reassessment. This Action Plan require that the Task Force analyze 2008 Action Plan reflects the Task Force’s efforts the broad landscape and policy changes that to track progress, update the science, and impact the hypoxic zone and water quality in adapt actions to improve the effectiveness of the Basin. These trends may include wetland the efforts throughout the Basin. Building on trends in both the upper and lower basin, the 2001 Action Plan, this plan lays out specific channelization of the Mississippi River and steps that need to be accomplished to reach how it affects the hydrology of the Mississippi the goals. It also reiterates the long term goals and Atchafalaya deltas, and the role of energy and continues the Task Force’s commitment and agriculture markets on land use in the to an adaptive management approach Mississippi/Atchafalaya River Basin. to reduce the size and impact of the Gulf hypoxic zone and improve water quality in the 2. Ensure greater specificity and Basin. This adaptive management approach accountability and tie to funding involves continual feedback between the strategies. The Task Force must identify the interpretation of new information and appropriate actions and engage State, Tribal, improved management actions and is the key and Federal agencies and stakeholders to to targeting actions within watersheds where identify the appropriate funding strategies that they will be most effective. will be the most effective in ensuring timely Mississippi River/Gulf of Mexico Watershed Nutrient Task Force . Gulf Hypoxia Action Plan 2008 Moving Forward on Gulf Hypoxia 5 implementation to achieve measurable and 5. Maximize opportunities for stakeholder effective results. involvement. Given the cooperative and voluntary nature of the Action Plan, the 3. Track program and environmental Task Force must engage a wide range of progress. The Task Force needs to improve stakeholders and facilitate broad acceptance of communication, better understand the the plan in order to maximize opportunities for results of its efforts, and improve tracking and stakeholders to pursue the identified actions. integration of results into improved design and targeting of adaptive strategies in future 6. Reexamine roles and responsibilities reassessments. of Task Force partners. A reassessment of the roles and responsibilities assigned to 4. Adapt to new scientific findings. the Federal agencies, the States, Tribes, and The Task Force has been active in soliciting the Sub-Basin Committees in achieving the and evaluating the latest scientific findings goals of the Action Plan will improve future through a series of symposia on relevant topics implementation and action. and advice from a panel of experts under the United States Environmental Protection Agency’s (EPA) Science Advisory Board. Mississippi River/Gulf of Mexico Watershed Nutrient Task Force . Gulf Hypoxia Action Plan 2008 7 Contents Moving Forward on Gulf Hypoxia 2 Framework for Action. 8 n Principles ..................................................................... 8 n Goals ......................................................................... 9 n Critical Needs ............................................................... 10 Progress and Reassessment 2001–2007. 14 n Trends in the Size of the Hypoxic Zone ........................................ 14 n Trends in Nitrogen and Phosphorus in the Basin .............................. 15 n Progress on Actions in the 2001 Action Plan ................................... 17 n Updating the Science ........................................................ .20 n Conclusions from the Reassessment .......................................... 21 Next Steps: Getting Results 28 Actions to Accelerate the Reduction of Nitrogen and Phosphorus. 29 Actions to Advance the Science, Track Progress and Raise Awareness. 42 Appendix 60 Mississippi River/Gulf of Mexico Watershed Nutrient Task Force . Gulf Hypoxia Action Plan 2008 Moving