As of Wednesday, the Truckee-Carson Irrigation District and the U.S. Bureau of Reclamation’s repair work on the Lewis waste-way structure was at about 20 percent, according to TCID’s website.
The work stems from a failure of the embankment adjacent to the structure on April 30. The construction is being performed by the district, BOR and Churchill County Road Department.
During the duration of work, district personnel instituted flow into the Carson Division through the T-line canal from Diversion Dam and through the Carson River channel. This will assist, in part, in making water available to the Stillwater area.
The repair design, meanwhile, consists of the placement of imported impervious fill, which will be compacted in 6-inch lifts to a 95 percent rate of compaction, according to TCID. Concrete low strength material (CLSM) will placed adjacent to the Lewis structure’s penstock and will be joined with the newly compacted material.
A sand filter and gravel drain will be placed in the downstream, or backside, of the embankment with additional material placed over the same.
Within the canal prism, a three-foot by three-foot cut-off wall will be installed in front of the structure and new embankment. The wall will also serve to anchor a geo-membrane that will effectively cover the entire front face of the embankment.
The geo-membrane will also be connected to the newly create Lewis waste-way facility as well as the existing check structure. The geo-membrane will then be “armored” by both a layer of impervious material and then by rock.
TCID will also post daily updates to the repair work on its website at www.tcid.org. Updates for Thursday’s construction efforts were not available at press time.