140 likes | 243 Views
Jacksonville Harbor Deepening: A Never Ending Saga. Quinton White , Jr ., Ph.D. Professor of Biology and Marine Science Executive Director, Marine Science Research Institute Jacksonville University. St. Johns River – Mouth to Jacksonville - 1791.
E N D
Jacksonville Harbor Deepening: A Never Ending Saga Quinton White, Jr., Ph.D. Professor of Biology and Marine Science Executive Director, Marine Science Research Institute Jacksonville University
Jacksonville Harbor Channel Improvements – First Dredging • Dredging of the 6 mile long channel commenced in June 1892 and took exactly two years. • The 15 foot deep channel permitted ships drawing 20 feet to dock in Jacksonville. • Prior to project completion, discussion about additional deepening commenced.
Jacksonville Harbor Channel Improvements – Deepening • After 6 years of deliberation (1902)Congress made an initial appropriation of $350,000 to start the dredging of a channel 24 feet deep and 300 feet wide, from Jacksonville to the sea. • By 1906 the work was completed and the 24-foot channel became a reality. • Ten years later, in 1916, another dredging project was started that resulted in a 30-foot channel from Jacksonville to the sea. • By 1924 ships weighted to 30 feet could dock at the municipal docks in Jacksonville at low tide. • Total cost of dredging and jetties: $7 million
Port of Jacksonville Project and Channel Improvements • 1880 – June; Jetties at entrance (maintenance only) • 1890 –Two jetties on Volusia Bar and 6’ deep channel • 1892- Secure 15’ deep navigational channel Dames Pt (RM 11) to Mile Point (RM 5) - Completed 1894 • 1896 – 24’ Jacksonville to Ocean & extend jetties - completed 1906 • 1910 – 30’ Jacksonville to Ocean – completed in 1916 • 1925 – The distance from the mouth to the FEC RR Bridge is 28.1 miles • 1930 - Widen bend at Dames Point to 900’ • 1935 - Widen Trout, Six Mile and Drummond creeks • 1945 – The river channel deepened to 34’ and the Dames Pt. Fulton Cut made – Federal Project 26.8 miles long. • 1965 – 38’ deepening completed in 1978 • 1998-2004 – RM 15 to mouth of the SJR deepened to 40’ • 2010 – Drummond Pt. to Tallyrand (5.3 mi) from 38 to 40’
St. Johns River Dredging Impacts: • Impact to benthic (bottom dwelling) organisms • Impact to salinity zones • Impact to marine mammals • Impact to flushing rates ( positive and negative) • Impacts to tributaries (positive and negative)
Mitigation • Very Difficult to Mitigate Salinity Changes • Corps had proposed to increase monitoring • The proposed monitoring has no mechanism to react if damage is discovered. • Monitoring is not Mitigation • Purchase of Credits from Wetland Mitigation Banks • Funding Nutrient Reductions that are already existing regulatory requirements • Restoration of the Ocklawaha River (removal/breaching of the Rodman Dam) has been withdrawn as an option
The Billion Dollar Question: Is it worth it economically for the environmental damage that will occur? And is there a better way to achieve the same end result?