The Commonwealth of Virginia is only one of many that contend that the computer model, or simulation, that the federal Environmental Protection Agency uses to guide the six-state bay cleanup has problems which make it difficult to accurately calculate exactly what individual localities need to do in order to meet the overall goal. Recently, the Richmond Times-Dispatch published a story which details some of the confusion citing the example of Charles City County who went from meeting 52% of sediment control requirements this summer to having a surplus capacity allowing an increase in sediment load of 406% in its latest update.
The article illustrates the uncertainties involved with the allocations established in the Bay TMDL, and the constraints due to the limited data. Although measures are needed to improve water quality in the Bay, finding a fair way to allocate pollutant loads, among states, local governments, non-point source and point source dischargers is a difficult challenge with economic consequences for all involved
http://www2.timesdispatch.com/news/chesapeake-bay-news/2011/oct/31/2/tdmain01-pollution-model-for-bay-hit-ar-1422615/#fbcomments