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4 Future Planning and Project Implementation for Coastal Restoration and Hurricane Protection ADAPTIVE PLANNING AND IMPLEMENTATION Due to the complex interactions of estuaries, wetlands, rivers, levees, sea level rise, and future changes in climate, plans within the LACPR project should be designed with some capacity to adapt to future, chang- ing conditions. Not only will environmental conditions in this vast re- gion change over time, but social and demographic conditions will change and initiatives such as nonstructural measures for reducing flood risk reduction (e.g., the adoption of flood insurance; the elevating of buildings in vulnerable areas; the number of structures that are relocated) will change and evolve in unforeseen ways. Monitoring of various physical and ecological change, as well as compliance with and success of various nonstructural programs, will be an important part of successful future adjustments in coastal restoration and hurricane protection. Monitoring of the performance of the hurri- cane protection system should be part of the systemâs ongoing mainte- nance and there should be regular considerations for altering the system in response to any adverse impacts. This is particularly true in the face of the LACPR study assumptions of no net loss of coastal lands. The outcomes from diversions will have to be monitored in order to adjust and improve future actions. Following up and adjusting programs re- lated to compliance with nonstructural flood risk reduction initiatives and incentives will also be important to their future performance and effec- tiveness. 33
34 Second Review of LACPR Draft Report TRADE-OFFS BETWEEN DIVERSIONS AND NAVIGATION The LACPR draft final technical report proposes nearly two dozen diversions to permit up to 525,000 cubic feet/second of sediment-laden water to leave the Mississippi River and flow into the wetlands for land building (USACE, 2009, p. 43, main report). These diversions would operate during the flood season. The diversion of this much water from the river would cause the riverâs flow rate to decrease. This would re- duce the riverâs scouring ability and would lead to additional shoaling. Diversions are featured within the LACPR report as a major supplier of sediment for restoration purposes (USACE, 2009, p. 219-220, main report). Diversions have large implications for the navigation sector, however, and the trade-offs between diversions and keeping water in the channel to support navigation are prominent, important issues. Remov- ing river water to create diversions for wetlands restoration, while also maintaining full navigational uses of the river, means that dredging costs will rise. Increased diversions imply reduced benefits for navigation, and vice versa. Despite the importance of these trade-offs, the LACPR team has conducted little analysis of them to date: It should be noted that the LACPR team has not deter- mined the cumulative impacts that multiple diversions may cause on the system. Nor has the team quantified the impacts on navigation or flood control on the Missis- sippi River (USACE, 2009, p. 219-220, main report). The LACPR team should more specifically identify and explain the trade-offs between commercial navigation and river diversions for coastal restoration. Current dredging in order to support commercial navigation yields large amounts of sediment from the bed of the Mississippi River. This sediment, if not contaminated, constitutes a valuable resource for the re- plenishment of wetlands and where possible should be put to beneficial use. The importance of capturing sediment or limiting its loss is a point that has been made previously in a number of reports. Historically, overbank flooding has provided sediment to the wetlands, but flood pro- tection by levee fortification has eliminated overbank flooding and con- sequently resulted in the loss of most sediment to the deep waters of the Gulf of Mexico. Minimizing the loss of this sediment off the continental shelf wilI be important to the success of efforts to preserve and restore Louisianaâs coastal wetlands.
Future Planning and Project Implementation 35 FUTURE SETTLEMENT AND INDUCED DEVELOPMENT A frequent consequence of levee construction is human settlement of areas behind levees, as these areas may be seen as safe for development and habitation. This phenomenon may take place in previously undevel- oped and uninhabited areas; similarly, it may occur in flood-damaged areas such as New Orleans, where settlement or resettlement may take place behind strengthened and raised levees. The negative consequences of this âinduced developmentâ were noted in this NRC committeeâs 2008 report, where it was stated that âPlans that encourage people to move into hazardous areas put them at risk in future hurricanesâ (NRC, 2008). The Association of State Flood- plain Managers likewise has concluded that levees âare inappropriate as a means of protecting undeveloped land for proposed developmentâ (ASFPM, 2007). The LACPR draft final technical report explains the importance of preventing induced development behind levees (USACE, 2009, p. 25, main report). The LACPR report explains the ways in which induced development was addressed in its report and the LACPR team deserves credit for recognizing the importance of limiting new settlement in haz- ardous areas. The LACPR report also appropriately recognizes the value of other related nonstructural measures, such as relocations, in signifi- cantly and reliably reducing flood risk (USACE, 2009, p. 36, Summary). Even though the concept of preventing induced development is en- dorsed, another portion of the LACPR report explains that âthe popula- tion of South Louisiana is expected to increaseâ (LACPR, 2009, p. 38, main report). Population growth and redevelopment policies are of course beyond the Corpsâ responsibilities; nevertheless, a program for reducing flood risks that sought to prevent induced development in vul- nerable areas would state clearly the reasons why the most vulnerable areas of southern Louisiana should be avoided and not resettled. There are of course many parties encouraging population growth in the region, but efforts to resettle people back into vulnerable areas will increase the flood risks to the city and its inhabitants and will not improve public safety. It is encouraging that the LACPR draft final technical report describes the importance of preventing induced development. The report, however, does not adequately demonstrate how these principles will be a prominent part of hurricane protection and coastal restoration actions. Discouraging development in particularly vulnerable areas, whether or not they are protected by
36 Second Review of LACPR Draft Report levees, is a fundamental principle of flood risk management and reduction. The LACPR should strengthen its cooperation with state and local entities to ensure that the prevention of induced development is accorded a more prominent and meaningful role in future plans. CONSTRAINTS OF THE CURRENT LEGISLATIVE SETTING The Corps of Engineers has responsibilities for numerous restoration and hurricane protection projects in southern Louisiana, under multiple authorizations. Although this reflects the traditional process of project authorizations through federal Water Resources Development Acts, it represents a piecemeal and poorly coordinated approach to ecosystem restoration and hurricane protection. If these projects are to be devel- oped and implemented in a coordinated fashion across all of coastal Lou- isiana, this current situation of multiple authorizationsâwhich may en- tail lengthy re-authorization processes if the Corps wishes to adjust op- erational goalsâwill hinder comprehensive, collaborative, and adaptive restoration and protection. The LACPR draft final technical report indicates that the majority of the improvements identified for final consideration therein could be im- plemented under the multiple, existing authorizations for hurricane pro- tection across southern Louisiana, either directly or by utilizing project change orders and that the remainder could be handled by new authoriza- tions; however, it is not clear that this is advisable. A good precedent for authorizing legislation for large-scale, adaptive ecosystem management projects, such as those that are needed to protect southern Louisiana into perpetuity, is the Comprehensive Everglades Restoration Plan (CERP). Authorized in the Water Resources Develop- ment Act of 2000 (WRDA 2000), the CERP is a 50/50 funding partner- ship with the State of Florida with a goal to ârestore, preserve, and pro- tect the South Florida ecosystem while providing for other water-related needs of the region, including water supply and flood protectionâ (WRDA 2000, Section 601). In addition to the enabling legislation, an accompanying report from the U.S. Senate Committee on Environment and Public Works explains the rationale and value of the CERP in promoting an adaptive approach to large-scale ecosystem management: The committee does not expect rigid adherence to the Plan as it was submitted to Congress. This result would
Future Planning and Project Implementation 37 be inconsistent with the adaptive assessment principles in the Plan. Restoration of the Everglades is the goal, not adherence to the modeling on which the April, 1999 Plan was based. Instead, the committee expects that the agencies responsible for project implementation report formulation and Plan implementation will seek continu- ous improvement of the Plan based upon new informa- tion, improved modeling, new technology and changed circumstances (U.S. Senate Committee on Environment and Public Works, 2000). From the outset of comprehensive restoration efforts in the Ever- glades, the Corps and the State of Florida recognized that they were charged to implement a large, complex portfolio of projects over decades and in the face of substantial scientific uncertainty. Their approach was to build in adaptation based on a major analytical and modeling effort and to seek congressional approval for a unique type of program authori- zation. The LACPR program is similar to the Everglades Restoration Plan in its spatial extent, hydrologic and ecologic complexity, and uncer- tainties regarding outcomes of future ecosystem restoration and hurricane protection efforts. The LACPR, however, presently lacks the kind of authorization that allowed CERP to move forward with a flexible, adap- tive program. Current legislation for coastal Louisiana hurricane protection and ecosystem restoration does not explicitly promote or provide for com- prehensive and adaptive planning. Examples of important scientific and planning principles that could be more explicitly encouraged include: â¢ There is a need to shed many outdated concepts such as levee height specifications that are tied to the Saffir-Simpson scale or the standard or maximum probable hurricane; â¢ Protection should be cast in a risk-based framework (e.g., 1,000-year protection) that is coordinated although not neces- sarily equal throughout the region; â¢ A mechanism is needed to specifically monitor changing envi- ronmental conditions (e.g., due to sea level rise and subsi- dence) and incorporate the findings into ongoing protection and restoration efforts in order to achieve successful, long-term adaptation; â¢ It should be possible to modify plans as new technologies,
38 Second Review of LACPR Draft Report such as improved hazard models, are developed; â¢ Projects should include beneficial use of all dredged materials (also see USACE, 2009, p. 225, main report); â¢ There should be a requirement of external review of new or substantially modified projects and periodic external review of existing projects; â¢ It is necessary to clearly delineate the roles of the federal and state governments in the collaborative design and development of a comprehensive system that includes coastal, structural, and non-structural protections and ties together initial system design and construction with long-term maintenance and op- erations using adaptive management. The multiple authorizations that govern ecosystem restoration and hurricane protection in southern Louisiana represent a piece- meal approach and may hinder integrated, adaptive restoration and protection improvements across the region.