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Evaluation of the Effect of Sea Level Rise on the C-111 Spreader Canal Western Project, South Florida This page is intentionally left blank. US Army Corps of Engineers ® Jacksonville District Please cite as: Landers, Glenn B., Mark Shafer, and Ariane O. Pinson. 2015. Evaluation of the Effect of Sea Level Rise on the C-111 Spreader Canal Western Project, South Florida. U.S. Army Corps of Engineers, Institute for Water Resources Responses to Climate Change Adaptation Pilot Study.Evaluation of the Effect of Sea Level Rise on the C-111 Spreader Canal Western Project, South Florida i Executive Summary The C-111 Spreader Canal Western Project is a U.S. Army Corps of Engineers (USACE) project under the Congressionally-authorized Comprehensive Everglades Restoration Plan (CERP). Past USACE construction of local canals for flood damage reduction and water supply benefits had the unintended impact of reducing freshwater flows and lowering water levels in wetland conservation areas along and inside the eastern boundary of Everglades National Park. The project uses pumps to restore historic freshwater flows in targeted wetland areas and provides a linear surface water feature to create a hydraulic ridge that prevents surface and near-surface groundwater from seeping out of the Everglades National Park. The C-111 project is a critical piece in a long-term effort to restore and sustain freshwater flows through the unique south Florida sawgrass wetlands, and to sustain estuarine conditions in Florida Bay and the coastal mangrove forests. Ecosystem restoration benefits are anticipated from the increased freshwater flows which will benefit significant areas of low elevation coastal wetlands along with the adjacent tidal and near shore shallow marine ecosystems in Florida Bay. Almost all of the project area is less than 6 feet above sea level, with much of the area below 3 feet above sea level in a coastal landscape with low relief, so long term sea level rise is anticipated to affec

An in situ seismic investigation consisting of surface refraction seismic, downhole, and crosshole tests was conducted at Lake Isabella, near Bakersfield, California. Compression and shear wave (P- and S-wave) velocities as a function of depth were determined for the main and auxiliary dams and underlying foundation materials. Results at the main dam indicated four P-wave velocity zones from a surface refraction seismic line located along the crest of the dam. These zones had velocities of (a) 1,750, (b) 2,550, (c) 8,050, and (d) 18,450 fps, which corresponded to (a) random fill material, (b) the central impervious core, (c) weathered granite, and (d) fresh granite. Data at the auxiliary dam were given two separate interpretations. The primary interpretation established three basic P- and S-wave velocity zones with respective velocities of (a) 2,850 and 1,150 fps for the embankment, (b) 6,600 and 1,600 fps for the foundation to bedrock, and (c) 12,100 and 3,300 fps for granite bedrock. The alternate interpretation provided a more detailed profile. Nine P-wave and eight S-wave velocity zones were established ranging from a low of 2,450 and 1,000 fps (P- and S-wave, respectively) to a high of 13,400 fps (P- wave) and 3,750 fps (S-wave) for fractured granite.

Seismic attenuation studies were conducted in two areas (A and B) where rock excavation is anticipated at the Portsmouth, Ohio, Gaseous Diffusion Add-On site. Ground and structure motions were measured from detonation of various charge weights to seismically calibrate the site and provide explosive use limits criteria for rock excavation operations. The data were analyzed and blasting criteria established as follows: (1) Charge limits which will minimize public annoyance and prevent residential or industrial structure damage at the site area included; (2) The probability of internal component damage in the moderately sensitive structures cannot be accurately determined because the available response data are insufficient. If the risk to moderately sensitive structures stated above is inacceptableunacceptable, then the Area B recommendations should applied to both Areas A and B or one of two other procedures should be followed. One is to gain additional data during the early phases of excavation blasting for further analysis and the second is to limit the charge/delay in 100 lb. The latter two procedures will reduce the risk significantly and in the last, the maximum charge/delay (100 lb) is no larger than that already used in a test at the site.