RESERVOIR SHORELINE EROSION STUDY PLAN TOLEDO BEND RELICENSING PROJECT FERC PROJECT NO. 2305

Transcription

1 RESERVOIR SHORELINE EROSION STUDY PLAN TOLEDO BEND RELICENSING PROJECT FERC PROJECT NO November 2009 Prepared by: Sabine River Authority of Texas Orange, Texas Sabine River Authority, State of Louisiana Many, Louisiana

2 1.0 INTRODUCTION 1.1 General Description of the Toledo Bend Project The Sabine River Authority of Texas (SRA-TX) and the Sabine River Authority, State of Louisiana (SRA-LA) (collectively, the Authorities) collaborated to develop the Toledo Bend Project (Project) located on the Sabine River. Construction was completed in October The Project is jointly operated by SRA-TX and SRA-LA through Toledo Bend Project Joint Operations (TBPJO). The Project was originally planned, licensed, and constructed as a water supply facility, but it also provides multiple uses, such as hydroelectric power generation and recreation. The Project is located approximately miles upstream of the confluence of the Sabine River and the Gulf of Mexico. Both the Project and this reach of the Sabine River, in which the Project is located serves as the border between the States of Louisiana and Texas. The Project reservoir (which is oriented in a southeast to northwest direction), is approximately 85 miles in length. The Project extends approximately 132 river miles (RM) (channel miles) from Toledo Bend Dam, which is located at RM 147.1, upstream to above Logansport, Louisiana (i.e., Murvaul Bayou), located at RM 279. The Project occupies lands and waters within Panola, Shelby, Sabine, and Newton counties in Texas and De Soto, Sabine, and Vernon parishes in Louisiana. Toledo Bend Reservoir is the largest manmade body of water in the southern United States and the fifth largest in surface area in the country. The reservoir has approximately 1,200 miles of shoreline with a water surface area of 185,000 acres at the normal maximum reservoir elevation of feet mean sea level (msl). The Toledo Bend Reservoir is 7 miles across at its widest point and contains a storage volume of 4,477,000 acre-feet between elevations 162 feet and 172 feet. Primary hydroelectric generation occurs between 168 feet and 172 feet. The watershed above Toledo Bend Dam is approximately 7,178 square miles with an estimated runoff in 2004 of 3.6 million acre-feet (SRA 2008). Over its 1 River Miles (RM) are measured along the river starting at the confluence of Sabine Lake and the Sabine River. 1 Reservoir Shoreline Erosion Study Plan

3 history, water levels have ranged from a low of feet to a high of feet. The Project Boundary is generally located at 175 feet. As currently licensed, the principal Project works consist of: A rolled earth-fill dam with a maximum height of 112 feet and a length of 11,250 feet (including saddle dikes); A reservoir with a surface area of 185,000 acres and approximately 1,200 miles of shoreline with an active storage capacity of 4,477,000 acre-feet; A concrete gravity spillway located on the left abutment (in Louisiana) with a gated ogee section and a concrete chute and stilling basin. The spillway has a maximum length of 838 feet with eleven 40-foot by 28-foot Tainter gates. The top of the gates is at elevation 173 feet and top of the spillway ogee is at elevation 145 feet. A continuous flow of 144 cubic feet per second (cfs) is provided at the spillway; A powerhouse located at the right abutment (in Texas) containing two 58,500 horsepower ( MW) vertical Kaplan turbines with direct drive generators, a tailrace channel, and appurtenant electrical and mechanical facilities. 1.2 Relicensing Process The current Toledo Bend license extends to September 30, The Authorities are relicensing the Project using the Integrated Licensing Process (ILP) as promulgated by Federal Energy Regulatory Commission (FERC) regulations issued July 23, 2003 (18 CFR Part 5). Pursuant to the FERC ILP regulations, the Authorities filed their Pre-Application Document (PAD) and Notice of Intent (NOI) with FERC on September 22, Following the Authorities filing of the PAD and NOI, FERC issued Scoping Document 1 (SD1) on November 21, 2008, and convened scoping meetings and a site tour for agencies and members of the public on December 16 17, Resource agencies and other stakeholders had until January 21, 2009 to submit comments on the PAD and study requests. The Authorities received comments and study requests from six resource agencies, one non-governmental organization, and FERC staff. In total, requests were submitted for forty-four studies, including a request by the U.S. Forest Service (USFS) to study wave action related soil erosion along the Toledo Bend shoreline. 2 Reservoir Shoreline Erosion Study Plan

4 On March 9, 2009, the Authorities filed their response to the comments and recommended studies that did not propose to adopt the USFS s proposed soil erosion study. On March 25, 2009, the Authorities held the required Proposed Study Plan Meeting with the agencies and stakeholders. Based on the comments and recommendations from this meeting and other stakeholder meetings, the Authorities prepared an updated Proposed Study Plan that was distributed for review and comment on May 27, Relicensing participants, including FERC staff, then filed comments on the updated Proposed Study Plans with FERC on June 8, The Authorities filed their Revised Study Plan document on July 17, FERC staff reviewed the Authorities revised study plans and the stakeholder comments received on those plans. Based on that review, the FERC Director of the Office of Energy Projects issued an August 6, 2009 Study Plan Determination approving the Authorities revised study plans with certain modifications. In response to the USFS request for a soil erosion study, FERC s Study Plan Determination required the Authorities to develop a new study plan to survey bank erosion on the Toledo Bend Reservoir. The FERC stated that this study should inventory the extent of shoreline erosion around the perimeter of the Toledo Bend Reservoir, and identify the effects of erosion on certain of the Project s natural resources. The study plan required by the FERC did not adopt certain elements requested by the USFS, including a comparison of past and present shorelines using historical imagery and the development of a predictive model to estimate future erosion. The goals of the Soil Erosion Survey required by FERC are to inventory the extent of shoreline erosion on Toledo Bend, identify effects of erosion on resources, and prioritize sensitive areas for erosion for possible inclusion in the Authorities Shoreline Management Plan being developed as part of relicensing. On August 26, 2009, the USFS filed a notice with FERC for dispute resolution of FERC s Study Plan Determination. As part of that notice, the USFS disputed FERC s treatment of its recommended soil erosion study. Specifically, the USFS notice stated that while it was clear that the cause of bank erosion along the shoreline is wave-action, the goal of the soil erosion study 3 Reservoir Shoreline Erosion Study Plan

5 should be to identify where erosion is on-going to determine site-specific mitigations. The Authorities responded in their September 21, 2009 comment letter on the Notice of Study Dispute that FERC s required study plan and the study proposed by the USFS seek to accomplish largely the same goals: to inventory the extent of the shoreline erosion around the perimeter of the reservoir, and then address the near-term and long-term management of erosion. In accordance with FERC s regulations, a Study Dispute Panel was convened and held a technical conference on October 6, In this conference, the USFS acknowledged that its dispute about soil erosion largely revolved around the study s methods that had yet to be formally proposed by the Authorities. The Dispute Panel found that the USFS erosion study dispute was premature because it was concerned with study methods that had yet to be developed. The Dispute Panel therefore concluded that there was no live dispute on the soil erosion study and recommended that the dispute be dropped. FERC, by letter dated October 14, 2009, indicated that the USFS agreed to withdraw the dispute concerning soil erosion since it will have an opportunity to provide input on the content of the Authorities study plan. With this, the FERC considered the study dispute withdrawn and required the Authorities to file its proposed study plan by November 30, As required by the FERC, the Authorities met with the USFS on November 20, 2009 to discuss the proposed study plan scope and methodology. At the meeting, the USFS was in agreement with the study plan elements as proposed by the Authorities. On November 24, 2009, the USFS filed comments to the FERC concerning the Soil Erosion Study Plan. In the letter, they reiterated that they agreed that the aerial videography appears to be the best method for assessing the current extent of erosion along the 1,200 miles of shoreline. Other comments by the USFS include: We encourage the SRA to conduct the surveys in 2010, rather than wait until Identifying soil erosion is important for other studies (i.e., cultural resources, special status species) and the Shoreline Management Plan. Consult with the USFS after the fixed-wing flights occur to discuss areas being excluded [from further study]. 4 Reservoir Shoreline Erosion Study Plan

6 Priority sites should also include the USFS shorelines that are highly susceptible to future erosion due to long fetches, erodible soils, short beaches, etc., even when known sensitive resources are not known. Provide a video DVD and GIS data for the USFS records. Consult with the USFS when designating priority areas as it relates to soil erosion. These comments are addressed in the methodology section of this study plan (Section 6.0). 2.0 GOALS AND OBJECTIVES The primary goal of this study, as required by FERC, is to inventory and characterize the extent of shoreline erosion around the 1,200 mile perimeter of the Toledo Bend Reservoir. The other goal of this study, as required by FERC, is to identify effects of Project induced erosion on resources such as cultural resources, aquatic habitat, recreation, wildlife and habitats, sensitive plants, and scenic resources. In accordance with FERC s directions, the overall objectives of the study are to: (1) Identify, using the agreed upon methodology, the areas and extent of shoreline erosion along the reservoir. (2) Identify and characterize shoreline erosion impacts on specific resources. (3) Identify how the proposed Shoreline Management Plan may serve as a mechanism for prioritizing, monitoring, and managing erosion impacts over the term of the new license. 3.0 STUDY AREA The reservoir shoreline erosion study will include all shoreline lands within the FERC Project Boundary surrounding Toledo Bend Reservoir (Figure 1.0-1a and 1.0-1b). 5 Reservoir Shoreline Erosion Study Plan

7 6 Reservoir Shoreline Erosion Study Plan

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9 4.0 BACKGROUND AND EXISTING INFORMATION 4.1 Resource Discussion In general, reservoir shoreline erosion is a process where the subjected shoreline becomes affected by natural and man-made induced forces such as wave action from wind and boat action (Holmes and Stallings 1987). Born and Stephenson (1973) considered shoreline erosion as a natural consequence of impoundment of a waterway with substantial topographic relief. This creates a condition of geomorphic disequilibrium and initiates wave front on a new shoreline. The new shoreline is not suited for its new environmental conditions and is easily eroded away. This appears to be the case at the Toledo Bend Reservoir. Holmes and Stallings (1987) considered the late winter/spring prevailing wind driven, wave action as the principal erosive force at Toledo Bend Reservoir. The USFS has also indicated that wave action is the cause of shoreline erosion at Toledo Bend (USFS 2009). The magnitude and rate of erosion is dependent on the vulnerability of the shoreline banks to forces that tend to flatten shoreline topography (Findlay 1993). With similar lithology (i.e., characterization of the rock formations) and erosive forces, shorelines that are steep generally erode at a faster rate than those that are flatter (Findlay 1993). Thus, erosion tends to slow over time as the geologic landform flattens and the system approaches equilibrium with the forces that tend to cause erosion (e.g., waves) (Findlay 1993). Findlay (1993) and Ferguson (1999) discuss how lithology affects the erosion magnitude and rate. For instance, sands erode at a relatively faster rate until a relatively flat beach or bench is established. The beach then limits further erosion through the absorption of wave energy through friction. The term beach refers to the section of the shoreline extending from the ordinary high water line to the critical water depth where wave action causes soil/substrate movement. The slope of the beach is dependent on soil type and the severity of the affecting force. The beach so formed serves to retard further erosion. Upon filling of a reservoir and during the early years after filling, steep banks slump shortly after submergence occurs because the increased groundwater level reduces slope stability and removes vegetation cover that has reinforced the soil allowing it to stand on slopes greater than the angle of repose (Findlay 1993). During this period, wind induced waves tend to easily reach 8 Reservoir Shoreline Erosion Study Plan

10 the shoreline, and the wave run-up tends to destabilize and flatten the banks. As the reservoir banks slump, the protective beaches form (Findlay 1993; Twenhofel 1961). The combination of flatter slopes due to bluff slumping and development of the beaches tends to reduce the erosive forces and gradually over time, a relatively stable shoreline develops. The beach that develops as the shoreline stabilizes is sufficiently flat to effectively dissipate the wave energy and prevent most waves from reaching the bank and thus limiting ongoing erosion. Born and Stephenson (1973) and Gatto and Doe (1997) indicated that reservoir bank slopes typically achieve stability within years of the reservoir filling or as the reservoir develops over time. The rate of erosion is fastest in the first few years of the impoundment or when shorelines are first submerged (Twenhofel 1961). 5.0 PROJECT NEXUS In accordance with FERC s ILP regulations, any request for an applicant to conduct a study must explain any nexus between project operations and effects on the resource to be studied (18 C.F.R. 5.9(b)(5)). According to FERC s Study Plan Determination letter, the Soil Erosion Survey being required by FERC is intended to identify the effects of erosion on water quality, aquatic habitat, cultural resources, recreation, wildlife habitat, sensitive plants, and scenic resources. The Authorities Cultural Resource Study Plan specifically includes an assessment of erosion related to cultural resources. With the exception of cultural resources, the Authorities continue to maintain that no study, data, or other information has been provided in any recommended study, comment, or other transmittal that establishes that Project operations are having an effect on the above resources. In fact, FERC s own Study Plan Determination letter states, [w]ith the exception of cultural resources, there is no evidence that such [erosion] processes within the project area are adversely affecting any other resources. The Authorities believe that FERC must balance the cost and level of effort of any study request with the need for the information requested. Because FERC has acknowledged that there has been no showing of any resource impacts (other than possibly cultural resources) due to shoreline erosion, and because the potential cost of surveying all 1,200 miles of reservoir shoreline is extreme and could easily be in excess of $500,000, the Authorities have developed what they believe to be an 9 Reservoir Shoreline Erosion Study Plan

11 appropriate level of effort for the conduct of this study. Applicable court precedents on this issue firmly establish that the license applicant does not have a duty during relicensing to search for problems and that there must be some hard facts supporting the need for a study. No such sitespecific evidence has been brought forward in this proceeding to date. 6.0 METHODOLOGY In general, the methodology associated with this study includes using aerial videography to identify shoreline erosion along the Toledo Bend shoreline. Using the erosion site information provided through the videography, a Geographic Information System (GIS) overlay map including sensitive site information gathered from other relicensing studies will be prepared for the study. The information that is gathered on sensitive resources will be overlain via the GIS, in relation to the known erosion sites. The intersection between these affected sensitive sites and known erosion sites may then be designated as priority sites to be field verified and monitored (i.e., rates of erosion) over the term of the new license through guidelines of the future Shoreline Management Plan. This methodology provides a high-quality, reasonable cost inventory of current shoreline erosion, and can provide useful information for the Shoreline Management Plan and the future monitoring of shoreline erosion rates. The SMP will include the anticipated protocols, methods, and schedules for monitoring the rate of shoreline erosion over the term of the license. Consultation with the FERC, USFS, and other stakeholders will occur throughout this process. 6.1 Identifying and Prioritizing Areas of Shoreline Erosion Geo-referenced Aerial Videography The Authorities will identify and document the extent of shoreline erosion along the Toledo Bend Reservoir. Shoreline erosion areas will be initially identified and inventoried through use of geo-referenced aerial videography of the Toledo Bend shoreline. Aerial videography was 10 Reservoir Shoreline Erosion Study Plan

12 determined to be an appropriate and cost-effective method for inventorying and documenting shoreline erosion along the approximately 1,200 miles of Toledo Bend shoreline. In a review of existing aerial photography for the project (e.g., 1995 color infrared digital orthophoto quadrangles [DOQs], natural color/color infrared National Agricultural Imagery Program [NAIP] photos), it was determined that these photos were not of a quality or accuracy that would allow reliable assessment of erosion sites along the shoreline and were thus insufficient to establish a baseline for future monitoring. Initially in the spring of 2010, a fixed winged aircraft will be used to identify relatively large stretches of shoreline where present and on-going erosion is unlikely occurring in order to eliminate these from the more intensive geo-referenced aerial videography. These areas are suspected to be those located in embayments or extensive wetland areas along the reservoir where slopes are low and wave action is limited by fetch and boat accessibility. These areas will be documented on aerial photography. GIS mapping and photography, detailing the areas potentially excluded from further study, will be provided to the FERC and USFS for consultation, discussion and approval. The aerial videography will be conducted along the shoreline of the main body of the reservoir (i.e., not the tributary arms) through use of a helicopter. The helicopter pilot will be instructed to fly at the appropriate altitude for identifying shoreline erosion sites but will not be asked to fly below safe limits. The usual flight height above the ground/water surface is feet. Generally, the goal is to have 80 percent of the video monitor consisting of the reservoir shoreline. The pilot will maintain a reasonable speed through the survey. However, speed and altitude will vary due to wind speed, constant turning, passing over powerlines, and flying with the correct color and lighting optimizing sun angle. The optimal sun angle for the aerial videography is typically between 10:00 am and 3:00 pm during a dry and relatively cloudless day. The reservoir water levels should be at levels lower than normal pool so that the erosion features are visible during the videography. The video will be shot with a Sony VX 2000 and recorded onto a Sony DV-Cam deck. The video will also be linked to the Geographic Positioning System (GPS) and will be connected to 11 Reservoir Shoreline Erosion Study Plan

13 the helicopter s intercom system to capture real time location of the erosion sites and facilitate cockpit communications. The camera will be hand-held by the experienced operator using a shoulder rest and pistol grip. The camera also has a built in electronic stabilizer. The finished video, to be provided to the USFS and other stakeholders, will include GPS coordinates of the erosion sites, a time stamp (hours; minutes; seconds; frames), and audio. Speed, altitude above the ground, and known landmarks will be audible on the video. The final product will consist of DVD(s) with a play selection menu that will allow the viewer to select different sections of the reservoir shoreline. The geo-referenced aerial videography provides a high-quality, reasonable cost inventory of the present shoreline erosion, and can provide useful information for the Shoreline Management Plan and future monitoring program. This erosion site identification phase (i.e., videography) will occur during leaf-off, winter conditions in January and February of Due to the current and anticipated above normal and high water levels throughout the winter and early spring of 2010, it will not be feasible to conduct this portion study in Erosion features would not be visible for the videography helicopter surveys. Given the fast-approaching and short duration of these specific conditions at the Project, there simply is not enough time to plan, contract, and fully complete all aerial surveys in 2010, following FERC approval of the study plan, especially in light of the currently anticipated above-normal and high-water levels throughout the winter and early spring of While the Authorities do not believe it feasible to fully complete the surveys in 2010, in response to the USFS s comments the Authorities propose to complete the fixed-wing survey in 2010, which will allow for initial GIS analyses and the preparation of an initial study report in Once the videography is completed in 2011, the Authorities propose to continue the GIS analysis and prepare an updated study report at that time. 12 Reservoir Shoreline Erosion Study Plan

14 GIS Mapping, Field Verification and Characterization Upon completion and review of the DVD of erosion sites, GPS coordinates of the representative erosion sites will be uploaded to GIS geo-referenced maps that will denote the FERC project boundary and general site conditions (e.g., soil types, fetch length). Using this base map, additional GIS data overlays will also be prepared for the study. The information that is gathered on sensitive resources such as cultural resource sites, recreational areas, and rare species sites and/or habitats (i.e., other relicensing studies) will be provided in relation to the known erosion sites. These affected sensitive sites may then be designated as priority sites to be field verified and monitored over the term of the new license through guidelines of the Shoreline Management Plan. Using this information, the Authorities will then conduct a field verification and characterization of these priority erosion sites around the Toledo Bend shoreline. These priority sites will be selected from the GIS analysis based on the presence of sensitive resources, as well as site location (e.g., west/east shoreline; peninsulas; USFS reservation lands), fetch length (i.e., the maximum open water distance across the reservoir-unimpeded by islands, vegetation or other obstructions), orientation of the shoreline, soil types (e.g., sands, clays), and vegetative cover. When selecting and designating the priority sites, the Authorities will consult with the FERC and USFS for discussion and approval. The field surveys will be conducted through observations via boat access and pedestrian surveys. However, it is not the intent of this study to inventory and characterize all the sites within or adjacent to the FERC project boundary. Representative sites for long-term, highly-accurate monitoring will be chosen using the following criteria. These criteria will be crucial in documenting baseline site erosion and for establishing the benchmarks in determining the rates of erosion over time. The SMP (filed along with the License Application) will include the anticipated protocols, methods, and schedules for monitoring the rate of shoreline erosion over the term of the license. 13 Reservoir Shoreline Erosion Study Plan

15 Position in Landscape o Embankment and levee o Steep bank o Floodplain terrace o Cove o Stream confluence o Relation to project boundary Shoreline Erosion Type o Undercut bank o Bluff slumping and slides o Rill and gully Parent Material Type o Fine sediments (silts and clays) o Sands o Loams o Gravel o Bedrock Physical Properties (dimensions and geometry) o Approximate height and width of erosion area o Shape and depth o Slope o Presence of beach deposit formation or other protective condition Vegetation Cover o Presence and absence o Type (herbs, shrubs, trees, vines) Adjacent Land Use o Undeveloped wooded o Undeveloped herbaceous o Developed residential o Developed commercial o Recreational 14 Reservoir Shoreline Erosion Study Plan

16 o Agricultural o Federal reservation lands o Known cultural resource site o Known recreational site o Known protected or sensitive species habitat 7.0 DATA ANALYSIS AND REPORTING In regards to this study, an analysis will include the results of the shoreline erosion area inventory (tabular and GIS mapping), results of the GIS analysis, and results of the site prioritization. The Draft and Final technical report on the results of the GIS analysis, field studies, and recommendations for monitoring will include the following elements: Project Introduction and Background Study Area Methodology Discussion and Analysis Results Discussion on the use of the potential use of the SMP for monitoring rates of erosion Location maps, GIS analysis and photos Agency correspondence and/or consultation Literature Citations Based on the information described in Section 6.0 (Methodology), an Initial Study Report (ISR) will be prepared that includes the study components (e.g., initial GIS analysis) and progress of this study to date. However, due to the early 2011 schedule associated with the aerial videography, inclusion of the study results in the Initial Study Report is not feasible. This information will be provided in the Updated Study Report (USR) to be filed in the fall of The ISR and USR will be submitted to the following agencies: Federal Energy Regulatory Commission United States Forest Service 15 Reservoir Shoreline Erosion Study Plan

17 United States Fish and Wildlife Service United States Parks Service Texas Commission on Environmental Quality Louisiana Department of Environmental Quality Texas Parks and Wildlife Department Louisiana Department of Wildlife and Fisheries Other interested stakeholders 8.0 SCHEDULE The anticipated schedule to conduct this shoreline erosion study is outlined below: 1. Study Plan Filed with FERC: November 30, FERC issues the Study Plan Determination: January 2, 2010 (tentative) 3. Study Planning, Fixed Wing Aircraft Reconnaissance, and Initial GIS Analysis Commences (Authorities): April 3, File the Required Initial Study Report (Authorities): October 30, Initial Study Report Meeting (Authorities and Stakeholders): November 15, Field Data Collection (aerial videography) Commences (Authorities): January 15, Complete Video and Provide DVD to Agencies and Stakeholders: March 15, RWG Meeting to Review Data and Select Representative Priority Erosion Sites: April 15, 2011 (tentative) 9. File Study Progress Report (Authorities): May 15, Field Data Collection Ends: July 11, File the Required Updated Study Report (Authorities): October 30, Updated Study Report Meeting: November 14, Updated Study Report Meeting Summary (Authorities): November 29, Study Disputes/Request to Modify Study Plan, if necessary: December 29, Responses to Disputes/Study Requests, if necessary: January 31, Director s Study Plan Determination, if necessary: March 1, Reservoir Shoreline Erosion Study Plan

18 9.0 BUDGET The estimated budget for the Shoreline Erosion Study is approximately $240, DISCUSSION OF ALTERNATIVE APPROACHES There are no established or standard scientific methodologies associated with FERC required shoreline erosion studies. In review of shoreline erosion studies performed at other FERC licensed hydroelectric projects, no known models that accurately predict rates of reservoir shoreline erosion over the long term were identified nor is there a standard approach for addressing this issue. The overall approach provided in this study plan, however, is consistent with FERC study requirements under the ILP and is cost effective and efficient in inventorying, characterizing, and prioritizing existing shoreline erosion sites around the Toledo Bend Reservoir. No generally accepted, feasible alternative methods have been identified at this time. 17 Reservoir Shoreline Erosion Study Plan

19 11.0 REFERENCES Born, S.M., and D.A. Stephenson Water Management of Shoreline Erosion Control in the Chippewa Flowage. Journ. Of Soil and Water Conserv. Vol. 27: Ferguson, B.K Erosional Process and Its Potential Control at Thurmond Lake. Proceedings of the 1999 Georgia Water Resources Conference. March 30-31, Athens, Georgia. Findlay, C PMF Erosion Analysis of the Bridgewater Development (Catawba-Wateree Project). Prepared for Duke Power Company. Gatto, L.W., and W.W. Doe III Bank Conditions and Erosion Along Selected Reservoirs. Environ. Geo. Water Sci. Vol. 9, No. 3, Holmes, W.H. and D.P. Stallings Toledo Bend Reservoir Shoreline Erosion and Soil Control Study. State Project No pp. 69. Twenhofel, W.H Treatise on Sedimentation. Vol. 2. Dover Publications. New York, NY. pp United States Forest Service Notice of Formal Dispute of FERC s Study Determination. US Dept of Agri. File Code August 26, Reservoir Shoreline Erosion Study Plan