The successful placement of this pipe is good news for the city of Seguin, Texas.
The city has experienced a series of major problems in its attempt to extend sewer service to the Oak Village North subdivision. Several years ago the city permitted its contractor to destroy a significant number of trees when the sewer line was installed adjacent to the Geronimo Creek at the Seguin Outdoor Learning Center on US 90. The contractor was faulted for its failure to provide portable toilets for its workers, at least one of whom lived in the woods during the project. The next phase of the project began when a new contractor installed a manhole directly adjacent to the creek on the north side of US 90. Subsequent floods washed out much of the soil around the upper section of the manhole's concrete structure, causing a defect that has yet to be properly repaired. This contractor ran into much more serious trouble when the foreman reported they had inadvertently formed a large void under the Union Pacific railroad track while boring under the track. The void was at least partially filled with 100 cubic yards of grout, which the foreman said was insufficient to fill the entire void. Shortly before Thanksgiving of 2011, the project passed under the IH-10 bridge over the Geronimo Creek and reached the point where the pipe would cross the creek. The engineering plan called for the pipe to be installed in a hole bored 5 feet under the bottom of the creek. However, the foreman reported that the pipe had arrived at the creek some 2 feet higher than expected and that he was concerned the pipe would penetrate the side of the creek instead of being installed 5 feet under the creek bottom. His concern became reality when the pipe pierced through the east bank of the creek. Water entered the pipe, flooded the boring trench and made it difficult to properly weld the sections of pipe to one another. The project came to a halt when the pipe was bent during an effort to complete the creek crossing. Seguin eventually filed suit against the contractor and its bonding company. In January 2013, a new contractor built temporary dams across the creek, pumped the creek water around the open section between the two dams, pumped the water from between the two dams, removed the defective pipe (which was lying on the creek bottom) and excavated a trench across the creek. A pre-welded 155-feet long, 30-inch diameter steel carrier pipe was successfully placed on a bed of gravel in the trench the evening of January 23, 2013, during a well coordinated operation by excavator operators whose respective machines on opposite sides of the creek lifted and then lowered the pipe by means of sturdy straps. The pipe was covered with a concrete cap the next day. Assuming this crossing performs as designed, the sewer pipes now being installed in the subdivision will be connected to the pipe that crossed the creek sometime during the next few months. Hopefully, the excavated banks of the creek will not experience severe erosion during the next rise and the vegetation and trees that once covered this major excavation project will eventually return.
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