PERSISTENCE PAID-OFF FOR WEST TEXANS
In the end persistence, compromise and environmental sensitivity brought the project into being. Construction of the O.H. Ivie Pipeline was initiated in August, 1992 and is expected to deliver its supply water to the Midland/Odessa area by February, 1995. Excavation of 156 miles of trench for 53 to 60-inch pipeline is no easy task. But project construction is expedited by development of a 200,000 pound monster trencher. Its enormous size and the strength of its 1,500 total horsepower diesel engines becomes evident when you feel the earth vibrating as it scrapes and saws through rock and dirt. Use of the machine is an innovation of installation contractor John D. Stephens. Stephens had carefully analyzed the soil conditions and terrain along the pipeline route prior to the bid opening. He found conditions ranging from miles of solid rock, miles of easy digging soil, and miles of west Texas blow sand: each condition occurring repeatedly. Stephens had a lot of rock trencher experience and he reasoned a machine just a little larger than he or anyone else had ever seen would he able to overcome all difficulties along the 156-mile pipeline route. He contacted Trencor Jetco and the result is the largest chain driven trencher in the world.
The contractor's calculated risk is paying off. The pipeline's start at Lake Ivie was mostly rock so the digging was slow with numerous breakdowns of the untried machine. At one point pipe supplier Gifford-Hill-American (GHA), had 12 miles of pipe strung out ahead of the machine. After installing around 20 miles of pipe in rock, easier trenching soils were reached and Stephens' crew really began laying. In fact, in one day they installed over 4,000 feet. When the contractor reached the end of the 60-inch Section I pipe at the City or San Angelo he had almost caught up with the pipe manufacturer. Increased pipe production combined with tougher laying conditions ahead should keep an adequate cushion of pipe between the con-tractor and Gifford-Hill-American. 
60-inch pipe stringing began at Lake Ivie, 40 miles east of San Angelo.
Lake capacity is 550,000 acre-feet.
This Jetco Trencher weighs more than 200,000 pounds, digs an 8' wide,
12' deep trench, and can trench through solid rock.
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