Bay Clean-Up Estimates Too Optimistic, If You Can Believe It
A recent analysis of Bay pollution reduction models by the Chesapeake Bay Program (CBP) found that half (18) over-estimated progress, most of the rest (15) were accurate, and a few more (3) under-estimated progress. I suspect this isn't much of a surprise to anyone who has spent any prolonged length of time around the Bay in the last decade or so. Despite undeniable and important advances (e.g, the flush fee), the region continues to grow astronomically, with ever-changing consequences.
The Program models seem to be relatively accurate in the case of point source pollution (e.g., sewage treatment plants), where a discrete discharge can be easily measured, but pollution from non-point sources, like farm fields, or septic systems is difficult to accurately gauge. In those instances, data from case studies has to be extrapolated to a much wider set of circumstances, and errors in the case study, or the appropriateness of the wider application, can skew the results wildly.
To reduce the margin of error in the models, CBP is doing experimental work on a number of pollution controls and best management practices. That data should be available by the end of 2008.