DC Water Tunnels Go Green
Published: Tuesday, February 4, 2014
Updated: Tuesday, February 4, 2014 02:02
The District of Columbia Water and Sewer Authority has proposed modifying its current $2.6 billion D.C. Clean Rivers Project to incorporate green infrastructure into the later stages of its expansive three-tunnel anti-pollution initiative in Rock Creek and the Anacostia and Potomac rivers.
“The D.C. Clean Rivers Project is currently being implemented under a federally mandated consent decree among the U.S. Environmental Protection Agency, U.S. Department of Justice, D.C. Water and the District of Columbia,” Green Infrastructure Planning Coordinator Bethany Bezak said.
The original plan, which was initiated in 2003, sought to construct three tunnels that would prevent water pollution in the Anacostia and Potomac rivers and Rock Creek due to sewer overflow caused by rainfall.
The overflows, which currently dilute approximately 1.5 billion gallons of combined sewage into the Anacostia each year, will be curbed by 98 percent when the D.C .Clean Rivers Project is tentatively completed in 2022
Since 2010, however, D.C. Water has been exploring a new modification to the original plan: green infrastructure.
“In contrast to gray infrastructure, which is the traditional method of building tunnels underneath the ground, green infrastructure engages in construction above the surface,” Bezak said.
Green infrastructure imitates the natural processes of storm water before entering the D.C. Water’s combined sewer system. Green infrastructure technologies include rain gardens, green roofs, infiltration basins and bio retention facilities.
“[Green infrastructure] will create new green jobs that are beneficial in the long-term scope,” Bezak said. “There is a long-term maintenance component to these green jobs that traditional temporary jobs during construction of gray infrastructure do not have, and this will raise employment.”
The proposal to implement green infrastructure would not affect the initial stages of the project, which include tunneling under the Anacostia River and are already underway.
“The initial phase of the project is currently being implemented, in which a large underground tunnel is being built,” Bezak said. “But the later phases that involve the Potomac River and Rock Creek is where we are proposing the changes.”
Under the new arrangement, a $90 million combined investment in green infrastructure in Rock Creek and the Potomac would replace the proposed Rock Creek section of the tunnel and significantly reduce the size of the Potomac tunnel, which would be completed in 2030.
“The construction of green infrastructure, if implemented according to the new proposal, will allow the District to see improvements in water quality as early as 2015, whereas the original plan would allow us to see the enhancements starting 2025,” Bezak said.
While enhancements to District water quality would only occur after the original plan, which calls for the construction of gray infrastructure, is completed in 2025, the new proposal allows for gradual improvements in water quality.
“The new proposal is like a step-by-step approach, where small construction will continue one by one,” Bezak said. “The original plan shows water quality enhancements in one significant blow at its completion, whereas for this new proposal we will see clear improvements in the quality of water each time one small part is completed.”
GUSA Secretary of Sustainability Gabe Pincus (SFS ’14) pointed out that the very presence of the tunnels is demonstrative of the District’s failure to support the environment.
“I think it’s unfortunate that we can’t accommodate the natural rainfall of the city, that we would even need to consider building a gigantic cistern tunnel under the river to hold all of our storm water runoff,” Pincus said.
Pincus explained that the tunnels would do little more than act as a Band-Aid for an ongoing problem.
“If we don’t adjust green space and permeable surfaces in the city, and the city continues to develop, and it inevitably will, if we don’t have standards for where we put green space in the city and how much there needs to be. And if it continues to develop, we’re going to continue to have increased storm water runoff, so building one storage container or two...that’s a patch. It’s not really addressing the root of the problem.”
D.C. Water is reaching out to local communities to collaborate on ideas as well as gain financial support for the project.
“Advisory Neighborhood Commission 2E is planning to work closely with D.C. Water and communities regarding D.C. Water’s green infrastructure proposals and/or any CSO tunnel proposals,” ANC2E Commissioner Jeffrey Jones said.
In turn, local communities also hope to hear more about the proposal and the potential direction toward which the D.C. Clean Rivers Project might move in the future.
“I am hoping D.C. Water will be able to present some of these plans at an ANC2e public hearing in the near future,” Jones said. “I am supportive of plans that promote a healthier environment for all of our residents while preserving and protecting the historic character, beauty and economic vitality of Georgetown.”