By Kacey King-McRae
Arlington County's Water Pollution Control Plant (WPCP) treats flow from nearly all of Arlington. In 2001, Arlington County officials recognized the need to address several long-term challenges. The aging infrastructure was becoming strained because of insufficient treatment capacity to handle wet weather events that could increase flows nearly fourfold.
In a forward-looking approach, the county board decided to proactively upgrade the plant's treatment process. The resulting planning, design and construction project was a $568 million, decade-long upgrade of the WPCP that would expand the plant's capacity from 30 mgd to 40 mgd while also reducing nitrogen and phosphorous to the limit of technology.