Florida Inland Navigation District: Permitting and Construction of the M 5 Island Offloading & Crossroads Maintenance Dredging and the NA 1 Upland

Size: px
Start display at page:

Download "Florida Inland Navigation District: Permitting and Construction of the M 5 Island Offloading & Crossroads Maintenance Dredging and the NA 1 Upland"

Transcription

1 Florida Inland Navigation District: Permitting and Construction of the M 5 Island Offloading & Crossroads Maintenance Dredging and the NA 1 Upland DMMA Facility Authored by Lori Brownell, P.E. and John Adams, P.E. Presented by Jim Marino, P.E., D.CE October 2012

2 Presentation Overview Long Range Planning Efforts for Florida General Dredged Material Management Plan Florida s Intracoastal Waterway Florida s Okeechobee Waterway Permitting Challenges in Florida M 5 Island Offloading and Crossroads Maintenance Dredging NA 1 Dredged Material Management Area Construction

3 Long-Range Planning Efforts for Florida Florida Inland Navigation District (FIND) established in 1927 USACE and State of Florida partnership Shifts in perception occurred in mid 1980s regarding dredging/dredged material management Taylor Engineering became the District Engineer in 1986 Dredged Material Management Plan development guided by Technical advisory committee Citizens advisory committee 12 county specific plans

4 DMMP Permitting Challenges in Florida DMMP Purpose: Assist the USACE with dredging operations in a manner dictated by economic and engineering considerations, and environmental and socioeconomic constraints Economic and engineering considerations Dredged Material Placement Areas (DMMAs) Material locations (shoals) Material volumes (cubic yards [cy]) Material types (sand, clay, silt) Environmental and socioeconomic constraints Natural resources Threatened and endangered species Cultural resources Adjacent land use and zoning restrictions

5 Florida s Intracoastal Waterway 404 channel miles within two federally authorized navigation projects Constructed to present depths Environmentally diverse Multibillion dollar economic impact 16 tidal entrances 5 deep water ports 60 placement sites 8 beach 52 confined upland placement sites 31 properties acquired 18 operational 1 final design/permitting 2 under construction

6 Florida s Okeechobee Waterway Expanding FIND s DMMP 1996 and 2005 legislation added 98 channel miles (4 segments) FIND total 502 channel miles Fundamental differences between ICWW and OWW Initially authorized and constructed for flood control/water distribution No history of channel maintenance Variation in lake levels Active phosphorus load reduction effort

7 M-5 Island Offloading & Crossroads Maintenance Dredging Economic and engineering considerations Island dredge material management area Diverse and challenging wind and wave conditions Tight beach compliance criteria Environmental and socioeconomic constraints Adjacent aquatic water preserve Active least tern and sea turtle nesting areas Offshore hardbottom Multiagency coordination County, FDEP, USACE, NMFS, National Wildlife Refuge

8 Project Overview Repeat Taylor Engineering project 1997 = 625,000 cy at M SLI A and M SLI B ICWW pipeline corridor Fundamental differences 1997 = DMMA construction 2012 = 350,000 cy between R59 and R80 Increased environmental scrutiny Beach pipeline corridor Crossroads Maintenance Dredging ICWW and OWW intersection 2 3 year dredging cycle 50,000 60,000 CY/dredging cycle M 5 DMMA Placement

9 M-5 DMMA M 5 capacity: 290,000 cy Intermodal area challenges Federal channel Wind and wave forces Gabions Adequate navigation depth Seagrass Mangroves

10 Beach Design Pipeline route Martin County easement Beach design challenges St. Lucie Inlet State Park Hobe Sound National Wildlife Refuge St. Lucie Aquatic Preserve OFW Vicinity of hardbottom Sea turtles

11 NA-1 Dredged Material Management Area Economic and engineering considerations Variable subsurface soil conditions Installation of wick drains Rigorous seepage and slope stability analyses Off site material required for construction Environmental and socioeconomic constraints Dense natural maritime hammock community Healthy saltmarsh and freshwater wetland communities Active planning coordination with USFWS, FFWCC, adjacent neighbors (Amelia Island Plantation and Fernandina Beach Municipal Airport)

12 Project Overview

13 NA-1 Unique Site Challenges Geotechnical conditions ICWW dredge material placed on the eastern side of the island between 1943 and 1960 Western soils comprise medium to dense clean silty sand (3 9 feet below ground surface) underlain by 5 10 feet of very soft clayey sand 1943 Aerial Photograph Environmental site conditions Narrow band of freshwater wetlands located between the eastern and western portion of the island lobes Centrally located eagle s nest 1960 Aerial Photograph

14 Summary of Settlement Analysis Results

15 DMMA Cross Sections Western DMMA Cross Section Eastern DMMA Cross Section

16 Summary Long Range Planning Efforts for Florida DMMP for ICWW and OWW ongoing since 1986 and 1996 Permitting and construction phases remaining Florida Permitting Improvements Advance coordination Active communication Government driven streamlined process Contact Information Jim Marino Lori Brownell John Adams