Table A4.4: Schedule of possible environmental effects identified in relation to freshwater flows and water quality

Energy supply and demand

Changing freshwater flows and levels for hydroelectricity generation

Increased pressure

Immediate

Waters of local, regional and possibly national significance could be subject to this pressure; likely to continue until at least 2020.

Moderate–high
Negative

Agriculture

Water abstraction for irrigation

Reduced pressure, but some uncertainty

Early–medium

Effect of ETS price signal will increase as 2013 nears; mixed changes in land use and farming practice expected, overall effect on water likely to be positive but small and hard to predict. Biofuels obligation not likely to have significant impact on water demand.

Low–moderate
Positive

Forestry

Afforestation effects on base flows

Increased pressure

Early

Effects can be locally significant in small to medium rivers and aquifers; will continue for duration of ETS-plus incentives.

Low
Negative

Transport

Local water pollution from road runoff

Decreased pressure

Early

Effects likely to be small due to inelasticity of demand for road transport; could be increased pressure in selected transport corridors.

Low
Positive

Agriculture

Nutrient and sediment runoff from intensive land use

Decreased pressure

Medium

Effectiveness of ETS-plus expected to increase over time. Significance hard to predict.

Moderate
Positive

Forestry

Effects on soil erosion and sediment yield

Decreased pressure

Medium

Erosion control benefits increase as trees grow, especially at canopy closure (~8 years). Will continue for duration of ETS-plus incentives.

Moderate
Positive

Forestry

Water quality impacts of harvesting

Increased pressure

Distant

New forests not expected to be harvested for 25–30 years. Effects can be locally significant.

Low
Negative