A CONSTRUCTIVE SOLUTION FOR OPTIMAL LOCAL-CONTROL OF RUNOFF EVENTS

The task of optimal local control of extreme rainfall-runoff events in sewer pipe systems is outlined and formalized as a mathematical optim ization problem applicable in many other similar situations. The goals of control, i.e. minimizing of overflow, uniform runoff to purificati on plant and effective use of retention basin, are transformed into a numerical expression with additional conditions. Along this measure th e continuous inflow has to be decomposed into the three parts ongoing pipe flow, overflow and basin inflow. Whereas the existence and unique ness of the solution can easily be realized, the derivation of a const ructive and computable solution of the problem requires some preparati on: For demonstration of the main theorem some auxiliary lemmas and an approximation proposition of general mathematical interest have to be proven. Some examples illustrate the calculation and application of t he control functions and their effects.