As the result of increasing pressure to be fiscally responsible, owners and operators of wastewater treatment facilities are being forced to maximize the capacity of existing facilities. Because the combined surface area of primary sedimentation tanks and secondary clarifiers can account for up to 50 percent of the total footprint of a typical wastewater treatment plant, the investment in these unit processes demands scrutiny. In addition, primary sedimentation tank performance has an enormous impact on the performance — and, therefore, the capacity — of downstream, biological processes; secondary clarifiers, on the other hand, often are identified as process bottlenecks that limit the overall capacity of many wastewater treatment plants.