Integrated Control of Combined Sewer Regulators

Integrated operation was simulated of 10 dynamic combined sewer regulators on a Montreal interceptor. Generally, when no in-line or other in-system storage can be called upon, advantage over local automatic-dynamic regulator control cannot be obtained by integrated operation of regulators. This happens unless expected flowrates to the interceptors can be estimated in advance of their actual occurrence; or unless an operational bias is introduced. These either minimize overflows from only some of the regulators on an interceptor, or favors the timing of overflows from all of the outlets, such as during the initial storm period. Computations for an actual system covering a summer season indicate even when a time-varying pollutant parameter is accounted for, the reduction in mass of a pollutant entering the receiving water under integrated operation of regulators may be only marginal. The potential for pollutant reductions at designated outfalls, however, is promising.