Technical Abstract: Foodborne disease caused by Salmonella is of public health and economic significance. In order to assess the practical effectiveness of a new intervention strategy, experimental chlorate preparations (ECP) were administered via the drinking water to weaned and finished pigs that had been orally challenged the previous day with 10**9 to 10**10 colony forming units of Salmonella Typhimurium. After 24 or 36 hours ad libitum access to 0X, 1X or 2X ECP treatment (0, 15 or 30 mM chlorate ion equivalents, respectively), the pigs were humanely euthanized and gut contents and lymph tissue collected at necropsy were cultured for the challenge Salmonella. Drinking water administration of ECP effectively reduced (P < 0.05) cecal Salmonella concentrations and tended (P less than or equal to 0.10) to reduce rectal Salmonella concentrations. Negative effects of ECP treatment on water intake and animal well being were not observed and only marginal effects on gut fermentation characteristics occurred. Because the bactericidal effect of administering the ECP treatments in drinking water was relatively rapid and because of its ease of use, the results suggest that ECP could be administered to pigs just days before slaughter to reduce gut concentrations of Salmonella.