Using the IRMOS model for diagnostic analysis and performance enhancement of the Rio Cobre Irrigation Scheme, Jamaica

Abstract The Rio Cobre Irrigation Scheme, Jamaica, supplies water to 5000 ha by allocating a fixed unit discharge at each offtake. A computer water management model, IRMOS, was used to assess the scheme’s performance during a typical operating year and to identify water management constraints to performance. An optimal water allocation policy was used as a benchmark against which the actual performance was evaluated. The comparison identified constraints in the scheme which can be improved by a variety of measures which include modifying the water allocation policy, operational procedures and physical components of the scheme. Despite the fact that operating under an optimal water allocation policy requires more data, better monitoring and a higher calibre of staff, the analysis shows that the potential benefits far outweigh the additional costs. The process shows how the use of modelling to identify performance shortfalls followed by management (rather than infrastructural) interventions can be a valid way forward to improving scheme performance.