Water quantity and water quality are major criteria for measuring the effects of forest management for bioenergy and bio-based products on water resources. Water quantity refers to the timing and total yield of water from a watershed, while water quality refers to the suitability of the water coming from ground and surface water supplies for drinking water, recreational uses, and as habitat for aquatic organisms and other wildlife (9). Water quality is measured using the following indicators:

• Biological: bacteria, algae, aquatic insects, fish, snails, and mussels
• Physical: temperature, turbidity and clarity, color, salinity, suspended solids, dissolved solids
• Chemical: pH, dissolved oxygen, biological oxygen demand, nutrients (including nitrogen and phosphorus), organic and inorganic compounds (including toxicants).