Technology and estimation methodologies have improved dramatically over recent years, making it easier to routinely, reliably and consistently estimate how well different conservation practices perform. For many BMPs, it is possible to estimate the environmental outcomes relating to water quality, soil erosion, air quality, greenhouse gas emissions, and water usage. Other environmental outcomes such as wildlife benefits, however, are not as easily estimated or quantified. Box 1 provides a brief overview of estimating environmental outcomes, and a supplementary policy note discusses this in more detail. Most likely, environmental outcomes would be estimated before a BMP is implemented with any payments being made after its implementation.

Estimating or measuring the environmental outcome(s) from implementing a BMP has many advantages, as it:
? Improves the rigor and consistency of ranking various BMPs;
? Enables farmers to provide compelling applications to conservation programs as they are able to specify the estimated environmental outcomes they would achieve;
? Will allow a more comprehensive assessment of any possible tradeoffs between multiple environmental outcomes;
and
? Can play an important role in determining the impact of these practices on the environment and more broadly for assessing the environmental outcomes associated with conservation programs.

Given there are now linkages between USDA environmental priorities and the environmental priorities in other federal agencies, measuring and estimating the performance of agricultural BMPs are also a way to support the goals of other agencies.

For example, the U.S. Environmental Protection Agency’s (USEPA) Total Maximum Daily Load (TMDL) legislation is explicitly listed in EQIP’s national environmental priorities relating to water quality. TMDL legislation identifies those watersheds that are impaired by pollutants and other factors such as nutrients, sediments, toxics, pesticides, excess salinity or increased temperatures, and places a limit on the amount of the identified pollutant(s) that can enter that watershed. Many state EQIP ranking systems award additional points to projects addressing water quality concerns in TMDL watersheds.

Any successful implementation of the TMDLs in watersheds where agriculture is listed as a source of impairment will require more quantitative approaches to measuring and estimating environmental outcomes from agricultural BMPs. This, in turn, will allow an assessment of the agricultural sector’s contribution to meeting broader federal and state environmental goals such as those associated with TMDLs.

One of the challenges with using quantitative measures or estimates of environmental outcomes is that currently not all USDA staff are trained in estimating environmental performance. Initially requiring them to make these assessments may potentially be constrained by limited staff time and other limited resources. However, these initial hardships could be overcome by establishing standardized estimation methodologies and technologies, and testing them on a smaller scale through pilot programs aimed at easing any transition to using quantitative measures or estimates of environmental performance. In time, USDA personnel would become comfortable with these procedures and view them as an efficient tool to rank their applications.