PROJ00527 - Laserfiche WebLink

Home Browse Search

I I I I I I I I I I I I I I I I I I I at a time so as not to impact the river fishery below the dam}, 5} lowering the plug into place with the plug valve open to pass leakage flow 6) closing the plug valve, opening the air vent valve and opening the gates to drain the outlet, 7} adjusting the plug valve to obtain the desired release of about 9 cfs, and 8) replacing the trash rack. The outlet closing process is expected to take one day but may take two if problems arise. The gate repair crew will begin work the second day by first placing the bulkhead upstream of the gate to be repaired first. To place the bulkhead, the plug valve will be closed to totally dewater the outlet for about one hour. The same contractor will probably be responsible for both the gate repair and the installation of the turbine piping so the work on the gates and piping should be more easily coordinated. Once the first emergency gate is repaired the outlet will be dewatered so that the bulkhead can be moved in front of the other gate which can then be repaired. When the two emergency gates are repaired and the turbine piping has been modified (see next chapter for details) the gates will be tested by closing them and filling the outlet pipe. The outlet pipe upstream of the gates can be filled in one hour with 14 cfs through the plug valve. The outlet gates may have to be opened for a few minutes each half hour to keep some flow in the river below the dam. The gates and turbine piping can be checked for leaks under normal pressure once the outlet is filled. If problems arise, further work can be performed; if not the plug can be removed as soon as the divers can be recalled. The divers will not remain in Durango, so a few days notice would be required for them to return. 6.0-10