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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />Williams friction coefficient of 105 for lined cast iron pipe. To better define the pipe friction <br />losses and phase capital improvements, Morrison could undertake testing measures to <br />conclusively determine the useful life of the existing 12-inch CIP. For calculation purposes, the <br />new stilling basin shown in the 1985 design has the intake of the transmission pipe at elevation <br />5990 feet. The water treatment plant is at elevation 5939 feet. The distance from the outlet of <br />the new grit chamber to the plant is estimated to be 3,700 lineal feet. The new grit chamber will <br />be located approximately 100 feet downstream of the headgate (which accounts for the total <br />3,800 lineal feet of pipeline). At present, the top of the pressure pipeline at the stilling basins <br />is at approximate elevation 5964 feet, and, with improvements, the upstream end of the pressure <br />pipeline will be raised 26 feet. The capacity of the existing gravity intake is calculated to be 3.3 <br />cfs, however, due to numerous leaks at the intake and the poor condition of the stilling basins, <br />the actual present delivery capacity is much less. <br /> <br />During a site visit on May 16, 1996, no leaks in the pipe or at the joints were visually evident in <br />the transmission pipe. This lined 12-inch CIP is a very heavy-duty pipe with a long life <br />expectancy under normal conditions. The walls of the pipe are nearly Y:z..inch thick, and the <br />inside cement lining was designed to reduce corrosion of the pipe. Visible sections of exposed <br />pipe show no indication of corrosion on the outside. A turnout located approximately 200 feet <br />upstream of the treatment plant allowed for a close inspection of the inside of the pipe, and <br />showed it to be in very good condition - although this turnout does not usually flow water and <br />may not be an accurate reflection of the main transmission pipe. The 12-inch CIP overflow pipe <br />at the water treatment plant was also inspected, and it similarly showed the inside of the pipe <br />to be in good condition. Aside from frost protection and repair of bullet holes in the pipeline, <br />Morrison has not had to replace any of the pipe recently, and therefore, the inside condition of <br />the main transmission pipe is unknown, although we suspect it is in good condition and not <br />tuberculated (bubbles of corrosion sometime seen in old iron pipe). <br /> <br />Lined cast iron pipe can have a life expectancy in excess of 100 years, if the lining remains in <br />good condition. Pebbles, up to one inch in diameter, have been reported in the weir manhole <br />at the treatment plant and could have damaged the lining over time. The inside of the pipe can <br />be inspected with a remote video camera by shutting off the flow at the stilling basin and <br />inserting a camera in the line at the stilling basin and/or through the manhole near the water <br />treatment plant. Using filming techniques commonly used for sewer lines, the camera can <br />typically extend a maximum of 500 feet into the line. Another testing technique involves <br />physically uncovering the line in certain areas and coring open sections of the pipe for <br />inspection. <br /> <br />70-080.035:MSTR-PLN <br /> <br />111-9 <br />