role of governments in addressing the water quality impacts of agriculture
TRANSCRIPT
What is Non-point Pollution?
• Enters water diffusely in the runoff or leachate from rain or melting snow.
• Generally a function of land use.
• Agriculture is generally recognized as the largest contributor of non-point pollution in the U.S.
Agricultural Pollution Has Some Important Characteristics
Uncertain water quality damages Uncertainty and randomness of flows Heterogeneity Inobservability Asymmetric information Time lags
Potential bases for policy
● Inputs and technology● Emissions (runoff or loadings)● Ambient quality
Performance-based policies would be based on emissions or ambient quality
Current programs largely technology-based
● Financial incentives for “best management practices”
● Land retirement
Performance-based instruments
● Emission taxes/subsidies● Emission standards● Ambient taxes/subsidies● Ambient standards● Trading
Options for Designing Performance-based Policy
● Models can be used to estimate environmental performance (expected emissions)
● USLE is used by USDA for program eligibility and to measure ex post performance
● Variety of models exist for estimating nutrient loss
● Expected emission-based incentives account for inputs, technologies, and resource base.
Measuring damages
• It is possible to estimate economic value of changes in water quality through various techniques such as contingent valuation and travel cost.
• Estimating benefits requires surveys that are generally expensive.
• There are methods for using existing values (benefits transfer), but the literature is very thin.
Environmental Indicators
● Quantify information so its significance is more readily apparent
● Simplify information about complex phenomena, such as nonpoint pollution
● Can be targets of performance-based instruments
● Serve as a metric against which progress can be measured
● Used to target policies
Examples of indicators
● Sediment production● Nitrogen runoff● Filter strips● Nitrate leaching● Pesticide leaching● Fish consumption advisory● Composite index
Education and Research
Cannot by themselves be expected to achieve cost-effective water quality control
Proven valuable in support of other approaches
Adaptive management combines assessment with adjustment
• Adaptive management can be used during program implementation to assess progress and changes in practice implementation that might be needed when models unavailable.
• Requires monitoring of water resource over time, and tracking the collective impacts of changes in management.
Summary Government has a role of developing policies
for reducing nonpoint pollution Performance-based policies are desirable Developing emissions or runoff models and
environmental indicators can enable greater use of performance-based instruments
The choice of a particular instrument depends on the local setting
Adaptive management enables improvements in policy over time