Advanced integrated wastewater pond systems for nitrogen removal

Wastewater treatment lagoons are well known for their effectiveness in removing biochemical oxygen demand, suspended solids, and pathogens of sewage origin. Their performance in removing fixed nitrogen is somewhat less recognized and documented. Advanced Integrated Wastewater Pond Systems (AIWPSs), developed at the University of California, Berkeley's Engineering Field Station and constructed at several locations in California and elsewhere, do permanently remove significant amounts of nitrogen from wastewater streams. A major part of this removal can be attributed to the unique design of AIWPSs. Because the unique characteristics of AIWPSs are not yet widely known and understood in the wastewater treatment field a somewhat detailed description of AIWPSs is in order. First, the basis for the name Advanced Integrated Wastewater Pond Systems will be explained. The term advanced is used because the design of AIWPSs represents an advancement over that of conventional waste stabilization ponds. The term integrated is used because these systems involve a number of well known and lesser known unit processes brought together in optimal sequence. The term pond is used because the individual bioreactors of an AIWPS are primarily constructed of earthwork. The term systems is used because the ponds are sequentially arranged and hydraulically controlled to optimize their multiple unit processes. The term wastewater is included to distinguish the function of these ponds from other types of water impoundments. Copyright (C) 1996 IAWQ. Published by Elsevier Science Ltd