Meltwater discharge and electrical conductivity were measured in eight 1¿1 m lysimeters, and snow accumulation and electrical conductivity of melted samples were measured in snow pits during four snowmelt seasons at Mammoth Mountain, California. The peak snow-water equivalent ranged from 0.57 to 2.92 m over the four melt seasons. Lysimeter discharges ranged from 20% to 205% of the mean flow; however, mean lysimeter flow was representative of snow ablation observed in snow pits. The electrical conductivity in snow pit samples and meltwater averaged 2--3 &mgr;S cm-1. Peak meltwater electrical conductivity ranged from 6 to 14 times the bulk premelt snowpack electrical conductivity. Snow depth did not affect the magnitude of the ionic pulse, and ion depletion as a function of snow ablation was similar from year to year despite interannual contrasts in melt rate and snow accumulation. Diel fluctuations in electrical conductivity were more pronounced in shallower snowpacks. ¿ 1998 American Geophysical Union