In July of 2011 Pat Johnston, Tom Erickson, Ryan Tangan and Seal went to Chamberlain SD to assist a company out of IL to inspect a pipe on a rural water system for PKG out of Fargo ND. Our job was to guide an ROV down a pipe at the bottom of the caisson so it could run the length of the pipe to check for any damage to the pipe. We arrived the day before and traveled out to the site to look things over and determine the best way to make the operation go smoothly. They could only have the system shut down for a maximum of four hours before they would run out of water in the system. When we arrived the next morning we were informed that the sensor for checking variation in depth in the pipe on the ROV was not working and also that there were bolts attaching the elbow to the pipe that were extending into the pipe, so there was concern that the ROV might not make it past them. The new sensor would not arrive until the next morning but it was decided to send the ROV down to see if it could make it through the pipe. Because of the high water the water in the caisson was up higher than normal, which made the job of lowering the divers down to the water and bringing them back out easier. The divers and gear had to be lowered down about 15 feet to the surface of the water. It was about 72 of water depth to the bottom of the caisson where the 90 degree pipe came up through the bottom of the caisson to a level of about 4 feet off the bottom. The ROV was lowered down first and then Ryan and Pat followed the cable down to the bottom. Seal was standby on the surface in the caisson and Tom was tender on the surface and monitored the communication system. Visibility was zero but the divers were able to lift the ROV and place it in the pipe. The ROV made the turn but was unable to climb the lip of the elbow and travel down the pipe. The operation was called off and we came back home.
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