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Virginia cities work to update sewer systems in advance of climate change test

A view of the CSX A-Line bridge over the James River. There are approximately 18 combined sewer outfalls downriver of this location, that release sewer overflow into the river during heavy rains.

RICHMOND — A viral video from September 2021 captured a person swimming in high water along a main intersection in Richmond usually walked by college students.

It rained just over 1.5 inches in a two-hour span that day, according to historic weather data. The rainfall burdened the city’s combined sewer system and created a significant flooding event that canceled evening classes at nearby Virginia Commonwealth University.

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Such heavy downpours are becoming more frequent in the U.S., according to the National Climate Assessment, a study presented every four years to Congress and the president.

An increase in temperatures due to climate change drives up evaporation rates, which leads to higher levels of water vapor in the atmosphere, according to the report. The result is more frequent and intense precipitation extremes.

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The increased heavy precipitation burdens the older sewer systems of Virginia cities like Richmond, Alexandria and Lynchburg. These cities, over time, have sent billions of gallons of untreated wastewater into state rivers during heavy rain events when the sewer backs up. All are actively working to upgrade their sewer systems, but there are concerns there is not enough funding to fix the issues soon enough, amid increasing precipitation rates.

Richmond’s project has the biggest price tag. The General Assembly adjourned without finalizing the state budget. The unresolved budget allots $100 million toward Richmond’s combined sewer overflow control project.

A combined sewer system moves wastewater from residential buildings and businesses, along with surface water and rainfall, through one pipe to water treatment facilities, where it is treated with chemicals to remove toxins and bacteria. The treated water then enters the James River and ultimately flows into the Chesapeake Bay, Hoffman said.

A separated sewer system has separate pipes for wastewater and stormwater.

Several parts of Richmond’s combined sewer system were re-piped starting in the 1970s, to separate sewer flow and help reduce stormwater sent to the treatment plant, according to Hoffman.

There are 25 combined sewer outfalls remaining, according to the Department of Public Utilities.

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Changing climate impacts flooding

The average annual rainfall in Richmond has increased by 10% since 1970, according to Jeremy Hoffman, the chief scientist at the Science Museum of Virginia.

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“This very old sewer system that we have in some places very quickly gets overwhelmed by the more intense and frequent rainfall events that we have now in a climate that’s consistent with the impacts of global warming,” Hoffman said.

The system is effective without heavy rainfall, Hoffman said. But, an inch or more of rainfall in 24 hours, depending on intensity and previous rainfall totals, can lead to sewer overflow. Hoffman pointed to the September 2021 flooding caused by under an inch, but in short time.

No one wants to swim, frolick or kayak in raw sewage. It can also cause gastrointestinal illnesses, according to Paul Bukaveckas, a VCU professor of biology and environmental studies. Bacteria and upstream livestock waste can also cause this illness.

“Harmful bacteria are those associated with fecal waste,” Bukaveckas stated in an email.

The sewage also impacts the James River ecosystem. The most recent “State of the James River” report card gave river health an overall B-minus, and a C-plus for river restoration efforts. Those efforts include stormwater pollution controls and bacteria reduction, which is part of a massive sewer project underway.

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The plan with a billion dollar price tag

The combined sewer system currently services one third of Richmond, according to Justin Doyle, director of community conservation at the James River Association, which publishes the annual report card. Richmond has already invested an estimated $315 million over the years to improve the combined sewer system, according to Doyle.

Lawmakers passed a bill three years ago to eliminate by 2035 the combined sewage overflow from any location east of Charlottesville that dumps into the James River watershed. Last year lawmakers proposed legislation to move the timeline to 2030, but it did not pass over funding concerns. The same senator who sponsored the legislation moved the timeline up for Alexandria’s CSO project, although it has a smaller price tag.

The 2020 bill outlined several planning and construction timelines with July due dates:

‒ Interim plan guidance by 2021

‒ Final plan by 2024

‒ Construction of interim plan projects starts by 2022

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‒ Construction of final plan projects by 2025

‒ Complete interim plan construction by 2027

‒ Identify any additional actions to meet overall timeline, by 2030

‒ Complete construction by 2035

The legislature can also extend project deadlines in light of fund availability and other factors that could affect the project.

Richmond City officials have started work on the interim plan, which consists of 10 projects. The combined cost is over $30 million, according to Doyle.

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“They’ve secured funding to do that and they’re actively working to implement those projects,” Doyle said.

Those interim projects fall under four overall strategies:

‒ Leverage storage to reduce CSO overflow

‒ Replace some equipment controls to help with overflow and diversion

‒ Maximize flow sent downstream for treatment to prevent premature CSO overflows

‒ Improve control strategies at some CSO management facilities

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The investments so far have helped reduce over 2 billion gallons of sewer overflow a year, stated Rhonda Johnson, public information manager for Richmond Public Utilities. Once the interim plan project is complete, overflow will be reduced by approximately 182 million gallons.

“This work involves many things — sampling of storm events, evaluation of data and updates to models used in assessing proposed projects for water quality improvements and reduction in overflow volume and number of events,” Johnson stated in an email.

Development of the final plan to completely upgrade the sewer system and stop sewage overflow is currently on track, according to the 2022 interim report.

However, Richmond needs a much higher investment closer to $1 billion dollars to meet the 2035 deadline, according to Doyle.

That needed amount is not far off from the city’s total annual budget, Doyle said.

The final plan projects have yet to be defined, according to Johnson.

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How citizens can help

There are two potential approaches to help reduce overflow, according to Shruti Syal, assistant professor of Urban and Regional Studies and Planning at VCU.

The first of these, gray infrastructure, is what the city is working to do, according to Syal. That involves replacement of combined sewer systems with separated systems, increasing wastewater treatment capacity and building wastewater storage facilities.

Green infrastructure strategy is the use of rain gardens, rain barrels and green spaces to help divert water from entering the sewer system. That takes educating citizens and stakeholders, which the city has begun to do through environmental outreach and literacy, according to Syal.

Green infrastructure can benefit communities in other ways, according to Syal. For example, planting a community garden to prevent runoff can also help address food security issues in lower income neighborhoods.

Such efforts are often siloed among organizations and individuals, without a framework to connect and streamline their efforts, according to Syal.

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The Science Museum of Virginia leads projects to reduce combined sewer overflow, according to Hoffman. Recently, the museum transformed a 3-acre parking lot in front of the museum into a park, Hoffman said. That will help absorb rain water better than asphalt.

The Science Museum of Virginia has also hosted workshops to educate Richmond residents about rain barrels.

“Rain barrels are basically things that they can actually install on their own homes, to harvest stormwater and to restrict it from going directly into the sewer,” Hoffman said. “We’re not only doing things on our campus, but we’re teaching others how to do it at their own homes.”

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Old engineering meets new climate change test

Heavier rainfall extremes due to climate change pose increased flooding threats, according to climate scientists.

The city’s flooding and overflow issues should begin to decrease as the city completes its upgrades, Doyle said.

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The biggest obstacles to completing the projects by deadline are time and money.

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State funding is uncertain at this point. Richmond Mayor Levar Stoney proposed a big funding bump in the upcoming Capital Improvement Plan toward the CSO project. Stoney proposed over $97 million, sourced from users fees and revenue bonds. The City Council is slated to vote on the budget on May 8. Richmond residents will see an increase in storm water and other utilities, the mayor said.

In the meantime, the city has worked to be more transparent about when and where sewage is entering the James River.

RVAH20 showcases the city’s progress, educates citizens and also monitors water quality.

People can check the Richmond Public Utilities map for public alerts when there is an overflow event.

It is recommended that people check the site and avoid swimming in the James River for several days after heavy rainfall, according to Bukaveckas.

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Capital News Service is a program of Virginia Commonwealth University’s Robertson School of Media and Culture. Students in the program provide state government coverage for a variety of media outlets in Virginia.


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