Hurricane Ike Caused Underwater Damage To GalvestonScienceDaily (Oct. 30, 2008) — Conducting a rapid response research mission after Hurricane Ike, scientists at The University of Texas at Austin surveyed the inlet between Galveston Bay and the Gulf of Mexico, discovering the hurricane significantly reshaped the seafloor and likely carried an enormous amount of sand and sediment out into the Gulf.
The ongoing research could help coastal communities gauge the effectiveness of their sometimes controversial efforts to replenish eroding sand along shorelines while revealing the role storms play in building and eroding barrier islands such as Galveston.
“The big question is whether the sand was entirely removed from the system or if it’s still close enough to the shoreline to get back into the system,” said John Goff, survey team member and senior research scientist at the university’s Jackson School of Geosciences.
Goff and Mead Allison, another research scientist at the Jackson School, used the 60-foot research vessel R/V Acadiana to conduct a seafloor survey of the Bolivar Roads inlet just a week and a half after Hurricane Ike made landfall on the Texas coast. The inlet is the main passage between the Gulf of Mexico and Galveston Bay and is the route of the Houston Ship Channel as it passes between Galveston Island to the west and the Bolivar Peninsula to the east. The team used sonar to map the depth of the seafloor and seismic instruments to measure the thickness of sediments.
The researchers knew the area well having led a group of university students on a marine geology and geophysics field class to Galveston this summer, collecting the most recent pre-Ike seafloor mapping and sample data from Bolivar Roads.
“The timing of our previous study was fortuitous,” said Goff, “adding to the practical and public benefit of our post-Ike data.”
Hurricane Ike’s surge last Sept. 13 filled Galveston Bay with 12 feet of water, which subsequently drained back into the ocean as a “back surge.” Although considerable amounts of water flowed over the Bolivar Peninsula and other lower-lying portions of the barrier system, most of the surge and back surge likely passed through Bolivar Roads, by far the deepest access between the Gulf and the Bay. The very high rate of flow that must have passed through the inlet had the potential to cause substantial erosion and transport sediment long distances.
Comparing pre- and post-Ike surveys, the scientists determined the hurricane’s surge and back surge significantly modified the seabed over broad areas. Ike either erased or substantially degraded large shell-gravel ridges up to 10 feet high. The storm gouged out sediments deposited hundreds of thousands of years ago to create “erosional pits” up to five feet deep in one area. It appears to have mobilized and redeposited sediments over large regions in a layer eight to 40 inches thick, and in isolated spots up to 6.5 feet thick. Most of the movement of sediments is associated with the back surge.
In conducting their post-Ike survey, the scientists are primarily interested in investigating the impact of the storm surges on the movement of sediment into and out of the beach barrier system. Maintenance of a barrier system requires an influx of sand, provided naturally by rivers such as the Mississippi. Human modifications to rivers by dams or levees disrupt the delivery of sand to the shore, which can cause the barrier system to degrade.
Until now, the transport of sediments during large storms was a poorly known quantity. Surges could potentially boost the barrier island sand budget by delivering sediments to the shore face, or they could subtract from it by moving sand too far off shore to be incorporated into the barrier system. The pre- and post-Ike survey work will also identify any storm-affected changes to the inlet channel that could affect navigation.
Weather permitting, the team will conduct an additional survey Nov. 6-8 offshore of Bolivar Roads to identify the extent of storm-related deposition, and offshore of the Bolivar Peninsula, where aerial and satellite photos suggest significant amounts of surface erosion during the back surge and consequential deposition off shore. Jackson School researcher Sean Gulick will also participate in this extended effort.
Funding for the survey was provided by the Jackson School’s Rapid Response Program, which funds field research requiring immediate action, in advance of the months it often takes to receive federal or non-profit grant money. Such projects include research into the effects of natural disasters like sinkholes, hurricanes, earthquakes and tsunamis.
WEATHER NOTE
2008: A record year for tornadoes
BIRMINGHAM, Ala. (AP) - Its been a record year for tornadoes in Alabama, so says the National Weather Service.
According to meteorologists, mother nature spawned 78 twisters through August of this year.
That breaks a previous record of 77 tornadoes in 2005.
The dangerous storms were responsible for five fatalities and 70 injuries statewide.
NWS said the worst tornado outbreak in 19 years occurred Feb. 6 when two violent EF4 twisters touched down in the Tennessee Valley.
The highest number of injuries occurred Feb. 17 when two strong tornadoes touched down near Prattville and were on the ground for 25 miles.
On the Web: www.spc.noaa.gov
GSA Launches Program to Support State and Local First Responders
State and local governments have a new way to buy supplies and services to prepare for and respond to all types of emergencies under a program established by the U.S. General Services Administration (GSA) earlier this month.
The Cooperative Purchasing Program allows state and local agencies to buy law enforcement, security, and first responder goods and services off a GSA contract known as Schedule 84. The interim rule implements the Local Preparedness Acquisition Act, signed by President Bush on June 26, 2008.
“Access to Schedule 84 will help our state and local government partners make their communities safer today,” said GSA Acting Administrator Jim Williams.
The GSA Cooperative Purchasing Program was started in 2003 to allow state and local governments to procure information technology equipment, software, and services found under Schedule 70 and Consolidated Schedule contracts containing IT Special Item Numbers. Under the expanded Cooperative Purchasing Program, state and local governments can also buy total solutions for law enforcement, security, facilities management, fire, rescue, clothing, marine craft and emergency/disaster response equipment.
As individual Schedule 84 vendors agree to participate in the program, a blue over red (COOP/PURCH) icon will appear next to their company name and the products/services displayed in GSA E-library and GSA Advantage. In addition, state and local agencies can purchase products and services from Schedules 70 and 84 under Cooperative Purchasing from GSA Advantage.
MARINE NOTE
Thursday, October 30th, 2008
Washington, DC (October 30th 2008): The National Transportation Safety Board has determined that the probable cause of the M/V Kition's collision with the Interstate Highway 10 bridge in Baton Rouge, Louisiana, was the pilot's attempt to execute the high-risk maneuver of turning at the dock immediately above the bridge rather than moving the vessel downriver through the bridge before turning, or taking it well upriver, then turning.
"This accident involving a large ship carrying a load of carbon black (a petroleum product) striking a highway bridge could have been catastrophic," said NTSB Acting Chairman Mark V. Rosenker. "It is imperative that we make sure that an accident like this does not happen again."
On February 10, 2007, the Kition, a Bahamas-registered tankship, was scheduled to depart Port Allen, Louisiana, on the Mississippi River. A state-licensed pilot, as required by Louisiana law, and three tug boats were on-hand to move the nearly 800-foot-long vessel away from its berth at the Apex Oil terminal and turn the vessel around to head downriver. The state pilot directed the movements of the Kition and issued all orders to the tugs. During the maneuver to turn the vessel down river from the dock, its starboard bow struck the bridge pier, knocking out a section of concrete and severely damaging the bridge fenders. There were no injuries or pollution and the accident did not affect the safety of the bridge. However, the vessel did sustain damage to its hull.
"Proper training would have prevented this accident." Rosenker said.
As a result of this accident, the Safety Board made the following recommendations:
• To the Board of New Orleans-Baton Rouge Steamship Pilot Examiners for the Mississippi River:
1. Verify that the pilots assigned to challenging locations such as the Apex dock have received adequate training in docking and undocking large vessels at such locations.
• To the United States Coast Guard:
2. Retrain your investigating officers in the policy set forth in ALDIST 174/97 regarding postaccident drug testing by Coast Guard personnel.
3. Verify whether the regulations for alcohol testing after serious marine incidents are being followed, and if not, identify corrective measures.
The Board's report can be found on its website at the following link: http://www.ntsb.gov/publictn/2008/MAR0803.pdf
NTSB Reference: SB-08-50
Forty-two dead, nine missing following Philippine ferry accident
MANILA (AFP) — The death toll from a ferry accident in the central Philippines rose to 42 Wednesday with nine people still missing, officials said.
The wooden inter-island ferry overturned Tuesday when it was hit by a freak whirlwind just 20 minutes after leaving port, where weather conditions were described as calm and clear.
Local civil defence chief Raffy Alejandro said the ferry was carrying 151 passengers and crew, well in excess of the 119 people listed on the manifest.
Of those on board, 100 have been rescued, 42 are dead and nine are still missing.
"This will be subject of an investigation by the coast guard since apparently it was overloaded," said Alejandro.
It is a common practice for inter-island ferries to be overloaded with last-minute passengers who board without being listed on the manifest.
The captain of the vessel, Dante Bumbales, has been found and turned over to coast guard officials investigating the incident, said local police chief Senior Superintendent Ruben Sindac.
The ferry had just left the port town of Dimasalang on the northeast coast of Masbate for Sorsogon port 80 kilometers (50 miles) away when it was hit by a sudden gust of wind and flipped over.
The accident came four months after the 23,000-tonne "Princess of the Stars" capsized during a typhoon off the central island of Sibuyan carrying 850 passengers and crew.
Only 57 people survived the accident, which was the worst maritime disaster in the Philippines for 20 years.
Mishaps involving ferries are common in this archipelago where many poor people rely on small, poorly-maintained vessels to travel between islands.
USCG – marine safety program independent evaluation
The US Coast Guard issued internal guidance stating that over the next four months an independent evaluation will be conducted of the agency’s Marine Safety and Marine Environmental Protection Program. In addition to examining a number of Coast Guard units, the evaluators will meet with various stakeholder organizations. ALCOAST 536/08 (10/28/08).
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