The error message:

===> WARNING !! NO CONVERGENCE IN SUBROUTINE CIRCLE.. ID = 1
ALPHA OR PSI = 8.9900000E-01 THETA1 = 5.7455417E+00

fills most of my Sanitary output file (171 MB!) so that not even Word can open it. I'm already running Tolerance=10^-6, and #Iterations = 75, and the simulation takes 9 hours for 22 years*12 pollutants. Behavior is the same for 10^-7 tol/100 iter. The continuity errors are fine (<2%) for both water and pollutants. How can the source of the error be detected and resolved, or the error messages suppressed? fyi, the last couple lines of CIRCLE subroutine are what generates the error. The condition of Q/Qfull= 0.89 is of course unavoidable during continuous simulation, however. The error messages prevent viewing any of the water quality summary output, as they are placed in the .out file after the input echo but before the useful output.

Thank you,

Gene Bosley
Parsons, Brinckerhoff, Quade & Douglas
Bosley@PBWORLD.COM