Ministry of Forests, Lands and Natural Resource Operations
Results:
when forest cover was removed from 50% of the area in the logged watersheds at Upper Penticton Creek, increases in water yield were measurable as a result of:
increased snow accumulation (10 – 25%)
increased rainfall reaching the soil surface (30%)
reduced water loss through transpiration and evaporation from the soil surface (15 to 30% of growing season rainfall),
although chemical and physical water quality was naturally good, the concentration of Mg, Na, K, N and suspended sediment in stream water increased slightly after logging and road construction, particularly during snowmelt and rain storms,
recovery of water quality indicators was rapid (~3 years),
aquatic invertebrate abundance and diversity were not adversely affected where stream channels and banks remained relatively undisturbed by logging
Practical applications:
consider opportunities to desynchronize snowmelt runoff within watersheds during cutblock layout,
identify and avoid potential sediment sources,
locate roads to minimise stream crossings,
keep logging slash out of creeks, and
limit harvesting in riparian zones and areas hydrologically connected to streams