Essential Dynamics

For decades Environmental Engineers have thought of, designed, monitored, and indeed managed our aquatic environment as though it were in a steady state, unchanging with time. Appreciating the natural dynamic behavior of environmental systems is now possibly. even for the processes generally believed to be very slowly responding. Contaminated surface runoff, for example, is quintessentially a problem of transient pollution. We can perceive it as a critical issue today precisely because there has been substantial investment in urban wastewater infrastructures; investment sufficient to improve water quality on average, sufficient in fact to reveal the transient impacts of storm events and other disturbances all the more dramatically. Such improvement brings with it new challenges and responsibilities: challenges, because any faults, failures, and mishaps in the system of sewerage and wastewater treatment will be all the more likely to happen -- more treatment plants with more and equipment to be operated without fail; and responsibilities, because the consequences of these mishaps will be much more obvious against the improved background, and indeed obvious to a much more environmentallly aware public. It is one thing to restore the environment to a state of good health; it is quite another to keep it in such good health.