Phosphorus Imbalances in the Chesapeake Bay Watershed: Can Forestland and Manure Processing Facilities Be the Answers?

A mixed-integer linear programming model was formulated to minimize the cost of transport and processing of excess manure in the Chesapeake Bay watershed. The results showed that primarily poultry manure was moved out of surplus counties for land application or processing. In the base model, annual cost was more than $350 million, with the bulk of the cost arising from construction of energy facilities for poultry manure. Forestland application of poultry manure had the lowest average cost, and more forestland than agricultural land was used for manure application. The lowest cost scenario was $127 million annually when constraints were removed to expand manure application on agricultural land and allow unlimited construction of composting facilities. Such a low-cost solution could not realistically be implemented without further development of markets for compost.