The South Dakota Department of Transportation is advising motorists the traffic signals at the Interstate 29 and Exit 73 interchange (Tea) are not operating under normal conditions. A malfunction, believed to be caused by a lightning strike, has caused damage to the control system and the signal is operating under an all-way stop condition until new equipment is installed. The signals are flashing red in all directions indicating that traffic must stop and may proceed when it is safe to do so. There will be considerable delays at the interchange, particularly during the morning and evening peak hours and motorist are encouraged to find an alternate route or allow additional time for their commute. The estimated time for repairs is the week of April 15, but subject to change based on equipment availability and delivery.