Fresh water injuries are often contaminated with bacteria that are not typically encountered in other wounds. Their treatment should include empiric administration of appropriate antibiotics. This study identifies the most common pathogens found in the Lake of the Ozarks and their antibiotic sensitivity. Eleven of the twelve lake water samples (92%) had a positive culture result. Sixty-seven percent of lake water samples contained at least two strains of bacteria. Five different bacterial species of gram negative rods were isolated. All isolates were sensitive to Cefotetan, Ceftazidime, Ceftriaxone, Imipenem, Levofloxacin, Tobramycin, and Trimetheprim/sulfa. Antibiotic coverage after traumatic wounds required gram positive coverage. Our study suggests the addition of gram negative coverage for penetrating trauma contaminated by fresh water.