Snow fencing to increase streamflow: preliminary results

A 3.8-m-tall snow fence 800 m long was placed on a 307-ha sagebrush-covered watershed in southern Wyoming in a paired watershed study. Snowmelt discharge increased 137%, snow accumulation increased 58%, and runoff was lengthened 18 days, over values predicted by pretreatment regression relationships the first 2 years after treatment. Overall water yield efficiency of snow stored in the fenced section was 32%, but yield efficiency of additional snow stored by the fence was 85%. Placement of additional snow over natural snow accumulations maximized water yield efficiency. The fence trapped virtually 100% of blowing snow.Average suspended sediment concentration in water was less than 11 mg/liter and deposition of coarse sediment was less than 0.11 cu m/sq km before and after fencing. Specific conductance of water ranged between 150 and 760 micromhos/cm at 25 degrees C; approximately 40% of the water samples had a conductivity between 300 and 400 micromhos/cm.