A 52 year old male oil well service owner died from injuries suffered while circulating a well with a crew of four workers. While attempting circulation, a lightning storm came up and the workers took shelter either in their vehicles or in a building adjacent to the rig, called a "doghouse". After the lightning had passed, the workers again began the circulation process. Rain was still falling, but there were signs of the clouds breaking up to the northwest - the direction from which the storm had come. The rig location was near a dry creek that occasionally filled during heavy rains. Large culverts had been built into the roadway near the rig to allow water to flow past the rig site. As a precaution, the victim had ordered vehicles to be moved from the low ground of the rig site to higher ground so that they would not get mired in mud caused by the rainstorm. Unbeknownst to the workers, heavy rain clouds had stopped over some hills to the southeast of the rig location, dropping excessive amounts of water on to that highground area. As the water flowed downhill it followed the path of the dry creek turning it into a turbulent river bed. When the workers saw large amounts of debris flowing down the river, they began shutting down the system. Three of the workers sought shelter in the doghouse, while the victim and another worker were shutting down the system on the circulator. One of the workers in the doghouse left to get a rope from the rig, saw the victim and a co-worker caught up in waist deep water, and attempted to help. The two co-workers were washed downstream and were able to hang onto a guy wire until they could gain sufficient strength to make their way to higher ground. The workers in the doghouse were protected by the enclosure. The victim's clothing was snagged by debris, pulling him under the water, where he drowned. Employers may be able to minimize the potential for occurrence of this type of incident through the following precautions: 1. Maintain constant watchfulness during inclement weather conditions, particularly at rig sites in lowland areas near creek beds. 2. Discontinue work processes when there is impending danger from a storm. 3. Always expect the unexpected and have procedures that can be quickly implemented in the event of an emergency.