Emergency　evacuation　traffic　is　simulated　in　response　to　an　assumed　chlorine　gas　spill　incident　in　downtown　Jackson,　Mississippi.　The　best　evacuation　corridors　are　identified,　and　possible　effective　traffic　management　strategies　are　compared　to　increase　the　cumulative　number　of　vehicles　evacuated　out　of　the　protective　action　zone　and　to　decrease　the　average　travel　times　for　evacuees.　To　relieve　the　heavy　traffic　congestion　around　the　spill　location　caused　by　the　sudden　increase　in　demand,　traffic　management　strategies　(law　enforcement　for　traffic　control,　contraflow　operations,　and　variable　message　signs)　are　tested　on　the　three　major　arterial　streets　in　the　protective　action　zone　to　improve　evacuation　performance　over　a　baseline　traffic　management　strategy.　A　multiway　analysis　of　variance　was　conducted　for　the　simulation　results　to　numerically　assess　the　effect　of　each　factor　that　might　contribute　to　the　performance　of　the　short-notice　evacuation.　Results　of　a　comparison　of　evacuation　scenarios　used　to　determine　evacuation　effectiveness　and　statistical　analysis　indicated　that　(a)　selection　of　a　best　contraflow　operation　route　depends　on　interference　from　intersecting　links　and　the　cost　of　deploying　traffic　management　and　(b)　the　use　of　both　contraflow　and　variable　message　signs　could　improve　evacuation　performance　over　using　neither　or　only　one　of　the　two　strategies.