Lufkin, TX -- Toledo Bend Reservoir on the Sabine River and Lake Nacogdoches have both played a part in the overall water operations connected with the Columbia Shuttle recovery. Since early morning, February 1, when area residents heard things falling into the water, the reservoir and lake floors have been searched for potential shuttle material.
When the National Aeronautics and Space Administration (NASA) mapped the path of the Shuttle Columbia, it became evident that some Shuttle material might have fallen into the Reservoir on the Texas-Louisiana border. Subsequent discovery of shuttle material in Sabine and contiguous counties along the projected flight path across Texas endorsed this conclusion. Radar data gave additional credibility to the possibility.
"We made a very early and well-considered decision to invite the U.S. Navy to coordinate an underwater search in the Toledo Bend Reservoir. This search we later expanded to nearby bodies of water as evidence of the debris trail came forth," said Scott Wells, federal coordinating officer for the Federal Emergency Management Agency (FEMA).
Bringing in the Navy to coordinate the overall mission was step one in the water operations. They have been working with teams from the Environmental Protection Agency, the U.S. Coast Guard, the U.S. Coast Guard Auxiliary, the Texas Department of Public Safety, the Texas Forest Service, Texas Parks and Wildlife, Galveston and Jasper Counties, the City of Houston, Sabine River Authority, and Louisiana Parks and Wildlife.
Currently, dive operations involve 146 persons, including five dive teams at Toledo Bend Reservoir and two dive teams at Lake Nacogdoches. Material assets, in addition to their boats, include two autonomous underwater vehicles (AUVs), two multibeam 3-dimensional imaging sonars, three side scan scanners, and the hardware and software appropriate for interpreting images returned by this instrumentation.
Diving in the Toledo Bend Reservoir is especially difficult. When the Sabine River backed-up to fill the reservoir in 1967, the fill occurred much more quickly than expected. As a consequence, divers are encountering an incredible number of obstacles, the foremost of which is the forest, with its tens of thousands of trees, branches, stumps and root balls which clutter the reservoir bottom. Additionally, many remnants of this East Texas community are frequently found by divers including railroad tracks, bridges, barns and houses, cars, washing machines, cranes, lawn mowers and wheelbarrows. The detritus of three decades of a premier fishing lake are also evident, with several sunken boats, outboard engines, canoes and boat batteries found.
These conditions dictate, in part, protocols for the dive. Divers wear dry suits due to the cold-water temperatures (averaging around 47 degrees Fahrenheit on the reservoir bottom), and use multiple breathing sources and specialized communications equipment due to the danger of entanglement with bottom debris. For dives in excess of 60 feet deep, surface supplies systems ("hard hats" with breathing umbilicals providing air from the surface support crafts) are used due to the increased danger of entrapment.
Search difficulties are further exacerbated by the turbidity of the water. In many places, divers can see no more than 20-30 inches, and when on the bottom, the sediment is easily stirred up resulting in zero visibility.
Regardless of this untoward environment, over 68 percent of the 14.69 square nautical miles of the search area has been searched using sonar, and divers have cleared more than 1,800 sonar identified targets, of which only one has been positively identified as a shuttle piece, and one other potential target is under examination by NASA.