Monday, April 23, 2018


In April the Potomac Watershed Roundtable met at AlexRenew in Alexandria, Virginia. In the morning meeting Karen Pallansch, the Chief Executive Officer of Alexander Renew spoke about AlexRenew, one of the most advanced waste water treatment plants in the United States. AlexRenew has more than 100 employees at their advanced waste water treatment plant that covers 35-acres in Alexandria. AlexRenew calls their plant a “Water Resource Recovery Facility” because it is far advanced of the sewage treatment plants of the past. The plant processes about 13 billion gallons of wastewater each year into clean water and reusable resources- Class A Biosolids.

During the past eleven years under the leadership of Ms. Pallansch, the waste water treatment plant was rebranded Alex Renew and saw significant treatment upgrades. Ms. Pallansch oversaw the implementation of a strategy that incorporated a successful public-developer partnership, creating a neighborhood from an area that once served as a City of Alexandria landfill. The new site, which opened in 2016, includes a LEED Platinum Environmental Center with an educational lobby. The building uses AlexRenew’s reclaimed water and is powered in part by solar energy and is where our meeting was held. Next to the building is an Envision Platinum Nutrient Management Facility topped with a multipurpose artificial turf field operated and maintained by The City’s Parks Department.

In short, AlexRenew is an innovative and inoffensive (it really doesn’t smell) waste water treatment plant and I had wanted to tour the facility since I read about it in Rose George’s excellent book “ The Big Necessity; the unmentionable world of Human Waste and why it matters.” I was not disappointed. You can take a virtual tour or sign up for an actual tour.

Before the tour Ms. Pallansch briefly spoke to the group about the history and operations of Alex Renew and in broad strokes of how they will help Alexandria meet the state legislative mandated timeline for solving the combined sewer overflow problem in Alexandria. There is an area of the City, mostly around Old Town that has a Combined Sewer System. This combined system is a piped sewer system in which there is one pipe that carries both sanitary sewage and stormwater to the local wastewater treatment plant. This was how sewer systems were commonly built in the days when sanitation was simply moving sewage out of the city to the rivers and streams. Back then one piping system was cheaper and adequate for the job.

However, today when sewage is treated by waste water treatment plants, the rain water that falls in the street and enters the storm water drains is combined with the sanitary waste water entering the sewers from homes and businesses. The combined flow can overwhelm the waste water treatment plant. So, to protect the sewage system as a whole, the combined sewage and rainfall is released into the local creeks in a controlled and planned fashion out of the “Combined Sewer Overflows” which are release locations permitted and monitored by the regulators.

Now Alexandria is under mandate from the state legislature to eliminate this problem by 2025. Though the state issued a mandate, they did not offer any funding to Alexandria or the right solution. In order to accomplish this, Alexandria has transferred ownership of the outfalls and the interceptor lines (the sewer mains transporting to the raw sewage to the treatment plant) to AlexRenew.

AlexRenew has taken the lead and based on feedback received during the Stakeholder Group process, they developed a plan that includes building a tunnel system with:
  • Storage tunnels 
  • Conveyance tunnels 
  • Diversion facilities (diversion chambers and drop shafts) 
  • Dewatering pumping stations 

AlexRenew upgrades including:
  • Wet weather pumping station 
  • Increase treatment peak capacity from 108 to 116 million gallons a day 
  • Wet weather treatment utilizing existing and improved facilities at the AlexRenew plant. 

Unfortunately, without funding from the state Alexandria residents will have to pay for the full project costs which are estimated to cost between $22-$40 per sewer connection per month to finance a project that is estimated at over $340 million.

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