The Washington State Department of Transportation says travelers who use Washington Highway 14 near Carson may experience delays with the start of work to improve the stability of two roadside slopes.  Work began Monday to stabilize two separate slopes located alongside SR 14, just west of Wind River Road, in Skamania County.  A large rock about three feet in size fell from one of the slopes in December 2013, blocking both lanes of the highway.  Crews will perform debris and tree removal, rock scaling, and installation of rock dowels into the hillside to secure the face of the rock slopes.   Once the rock dowels are in place, crews will add a layer of a concrete material against the surface of the slope.  There will be daytime, single lane closures on both directions of Highway 14 throughout the project, which is to be completed this fall.  During late September, there will be full roadway closures of about 45 minutes from 7 a.m. to 7 p.m. for rock scaling work, beginning at the top of each hour, with a 15-minute window to clear stacked up traffic.