They had the blueprint. Now they have the green light.
DC Water announced on May 8th that the National Park Service has approved the District agency’s preferred plan for rehabilitating the century-old sanitary sewer pipes running through the Soapstone Creek valley. The creek lies east of Connecticut Avenue at Albemarle Street and is also part of the DC Water stormwater sewer system. So Soapstone Creek is part of two DC Water systems and the work will impact both.
The sanitary sewer lines are decades past their design life. Called the “trenchless alternative,” the DC Water plan involves relining the existing 6,200 linear feet of pipes instead of replacing or digging them up entirely. Other major components of the project include repairing and protecting exposed pipes and manholes and repairing two stormwater outfalls that flow into the creek.
As stated in the June 2019 environmental assessment, the work will mean clearing staging areas and access paths for construction vehicles, and will require trimming and removal of several hundred trees. The stream bed will be disturbed because it will be necessary to gain access to the pipe within.
Also, parts of the trail will be closed when work is in close proximity. Off-trail areas will be closed for two years. And there may be times that streets and traffic will be impacted.
But trails will reopen as work is completed. The stream will be reconstructed. And NPS signed a finding of no significant impact, or FONSI, on April 14th and an memorandum of understanding on April 10th that commits DC Water to not only replanting trees that have to be removed, but also maintaining the trees for five years. You can find both of these documents here.
DC Water expects construction to start in winter 2021-2022. The agency is working on a public engagement process and will let the community know what that will entail and when.
If you’re not familiar with the project, Forest Hills Connection has covered the planning process extensively. You can catch up on it all here.
Green Eyeshades says
It has been almost a month since this article was posted. So this comment will seem very late. But just this morning, June 19, DCist revealed that DC’s Water and Sewer Authority (WASA), also known as “DC Water,” has released a June 2020 report admitting these crucial facts about rain gardens, permeable pavements, and other “green infrastructure:”
“… green infrastructure is too expensive in a densely built-up city like D.C. to be used on a large scale, according to a new assessment by DC Water.
“The water and sewer authority now plans to scale back its green infrastructure projects in the Rock Creek watershed, and instead build a 4.2 million-gallon concrete tunnel — ‘grey infrastructure’ — to capture stormwater until it can be treated.
” ‘When we projected what a 30-year cost would look like, green infrastructure was almost twice as expensive as grey infrastructure,’ says DC Water spokesman Vince Morris.”
[snip]
“When you add in operation and maintenance for 30 years, the cost of an ‘all green’ project for Rock Creek balloons to $407 million, compared to $211 million for an ‘all grey’ project.
“DC Water also found that some of the green infrastructure built so far was underperforming expectations — reducing stormwater flow into the sewers by only 18%, rather than the predicted 30%….”
https://dcist.com/story/20/06/19/dc-water-will-build-a-new-tunnel-to-prevent-sewage-overflows-into-rock-creek/
The DCist article links to the official report from WASA, but please do NOT click on it! The official report is over 1,200 pages long (102 megabytes!) because it includes the current (amended) consent decree issued by U.S. District Court against the EPA, and four score of other tables, figures, charts and appendices.
The official report apparently proposes many amendments to the consent decree, but discussion of the consent decree would be too detailed for a comment in the Connection.
Consistent with DCist’s quotes and summary, the Executive Summary of the official report states the following on page eight:
“DC Water compared the cost of all green to all gray to control CSO 049 in Piney Branch in Table ES-4. The cost to construct, operate and maintain an all green option is considerably higher than that of an all gray alternative. Projecting this over a 30-year period, implementing an all green option is approximately 95% more expensive than an all gray option. From a cost effectiveness standpoint, GI is not practicable in the Rock Creek sewershed.”
FHC says
Just throwing this out there: The DC Water Ward 3 virtual town hall is Thursday, June 26 at 6:30 p.m.
dcwater.com/ward3townhall
Alex says
This is a very interesting post. Thanks. It should be said that the goals and details of the Soapstone Valley Sanitary Sewer Rehab and the Piney Branch project are very different. The Soapstone Valley Project is meant to rehab active sanitary sewer lines and rebury them; these lines are separated and GI would not affect the flow within. The Piney Branch project has been imposed on DC Water via a consent decree in a sub-watershed where there is still regular combined sewer overflow; so DC Water must find some way to nearly eliminate that combined overflow.
In the Soapstone Valley watershed, introducing green infrastructure in the public and private space in the sub-watershed would reduce the stormwater runoff that scours the stream regularly, altered the stream’s ecology, and contributed to the exposure of the sanitary sewer lines. But GI would not change the fact that the many of the lines are over a century old and are overdue for replacement.
Green Eyeshades says
My comment on June 19 quoted from page eight of the Executive Summary of the DC Water report. On pages 1-2 of the Executive Summary (pp.9-10 of the 1,290 page PDF), the report states as follows:
“When the Consent Decree was amended, it was recognized
that GI [Green Infrastructure] had not been implemented previously on a large
scale in an ultra-urban area to provide a high degree of
CSO control. As a result, its effectiveness, cost, and practicality were unknown. The Amended [EPA] Consent Decree therefore provided for DC Water to construct demonstration projects in the Potomac and Rock Creek sewersheds and to evaluate their cost, performance, and other characteristics. Based on that evaluation, the Amended Consent Decree requires DC Water
to determine the practicability of GI…. Both the Rock Creek and Potomac sewersheds are required to be evaluated, and separate determinations may be made regarding the practicability of continuing with an all green application within the respective sewershed. This document presents the results of the practicability assessment for GI in the Rock Creek sewershed.”
That makes clear that the DC Water report applies to all of the “Rock Creek sewershed,” not just the Piney Branch part of Rock Creek, and that the report does NOT apply to the Potomac watershed. So the DC Water report applies to the Soapstone Valley watershed (or “sewershed” to use DC Water’s term) as part of the Rock Creek watershed. The 1,290 page report found that all Green Infrastructure is 95% more costly than all Gray Infrastructure (underground tunnels, etc.) for the entire Rock Creek watershed, not just for the Piney Branch section. That finding means that all Green Infrastructure is too costly to be implemented for the entire Rock Creek watershed (including Soapstone Valley).
On page 19 of the PDF, the report adds this possibly clarifying sentence:
“In the event DC Water determines that it is not practicable to control the required acres through the use of GI in the Rock Creek or Potomac sewersheds, the Amended Consent Decree currently requires DC Water to construct an all gray alternative. Both the Rock Creek and Potomac sewersheds shall be evaluated, and separate determinations will be made regarding the practicability of continuing with an all green application within the respective sewershed.”
But the report includes DC Water’s bid to amend the Consent Decree so that DC Water is not forced to build an “all gray” system. Instead, DC Water wants to build a “hybrid” system which is part-Green Infrastructure and part-Gray Infrastructure (pp. 9-10 of Executive Summary, PDF pp.17-18). I skimmed the first 70 pages of DC Water’s report and found no mention of Green Infrastructure in our area or in Soapstone Valley. There are general references to DOEE’s regulation of the Municipal Separate Stormwater Sewer System (MS4) and to green infrastructure built by DDOT, but no mention of Soapstone Valley or any area along Connecticut Avenue. I have no idea if DC Water’s hybrid system would affect Soapstone Valley or not, but the hybrid system is not currently allowed under the Consent Decree.
Alex says
Thanks for your close reading of the report. Of the sewersheds in the Rock Creek system, only Piney Branch still has a combined overflow system, so that would the only one (in Rock Creek) affected by this decision. The big tunnels are in the Anacostia. There’s another project in the Potomac too- roughly west of Rock Creek that will be affected by the decision.
DC Water’s concern has been to manage the sewer system; stormwater runoff has come into play in sewersheds where the storm and sewer combine and overflow into rivers and streams. Secondarily, runoff has impacted their physical assets (e.g. their pipes and manholes); but they’ve been quite clear that their sewer rehab projects, such as in Soapstone Valley, are meant to protect their assets, not to reduce stormwater. So unless stormwater helps to cause sewage overflows (as in Piney Branch), DC Water has concerned themselves with the impacts of the stormwater on their assets rather than the cause. And the cause is all the impervious surfaces in our watersheds.
Interesting (at least to me), is the wild card here- the National Park Service. DC Water would need NPS approval to build a tunnel under Piney Branch since NPS owns the land, and to my knowledge, they haven’t been enthusiastic about this. Even if they approve (eventually), the process will take years, thus setting back the goals of eliminating sewage from Piney Branch and Rock Creek.
Green Eyeshades says
During the extended discussion on this blog of the Soapstone Valley sewer rehab project, I posted one or more references to the extent of E. coli contamination in Soapstone Creek, which discharges into Broad Branch and then into Rock Creek. The Post and/or WAMU published at least one story about the extent of E. coli contamination in Rock Creek. So our Soapstone Creek is contributing to “sewage” overflow into Rock Creek, unless the E. coli contamination comes from deer, dogs, other wildlife or other sources in stormwater. Also, I can personally attest from numerous drives along Broad Branch that the creek develops a pungent and disgusting odor at certain times of the summer, which I have always assumed came from sewage overflow into Broad Branch. I would be happy if it were not true, but anecdotal evidence seems to show that we have a serious “sewage” overflow problem in our part of Rock Creek, which includes Soapstone Creek.
I don’t think we can think of Soapstone Creek as insulated from the larger context of the litigation over the EPA Consent Decree. The current Consent Decree requires DC Water to “control” 9.5 million gallons in the Rock Creek watershed. (The new report refers to that 9.5 million gallons in several places.) DC Water wants to build the 4.2 million gallon tunnel as part of its “hybrid” plan, thus that 4.2 million gallon tunnel is not necessarily required or permitted by the current Consent Decree. The DCist article was not clear on that point.
If DC Water wins the amendment to the Consent Decree that it wants, it will build the 4.2 million gallon tunnel, along with a wide variety of Green Infrastructure. I did not see any discussion in the new DC Water report about *where* the 4.2 million gallon tunnel will be built or any requirement that the tunnel be constructed *under* Piney Branch or *on* National Park Service land.
As far as I know, DC Water could choose to build the 4.2 million gallon tunnel wherever it wants outside of NPS land. But its June 2020 report seems clear that it can’t do that until it wins a District Court order amending the EPA Consent Decree.
Alex says
I urge you to review the many articles on the Soapstone Valley sewer rehab project published, including those in the Forest Hills Connection. Several include reports that provide extensive details on the goals and intentions of DC Water in the Soapstone Valley project.
Most streams in the Rock Creek watershed have some level of E. coli. contamination. Barring an accident or break (which has happened in the past), we just don’t know exactly what the source is. It could be from animals, from illegal sewer hookups into stormwater pipes, or it could be from sewage leaks in the sanitary sewer lines. There are, however, no connections between the sanitary lines and stormwater pipes in a separated system. DOEE and DC Water have been quite aggressive in dealing with sewage leaks and illegal hookups once they are detected. It is possible that a consequence of the Soapstone Valley sewer rehab project will be to reduce E. coli. contamination in the creek, though to my knowledge, DC Water has not detected any leaks recently. There is venting from certain manholes in Soapstone and elsewhere that smells of sewage.
There have also been many articles about the DC Water Clean Rivers Project and the consent decree. DC Water has an entire web page on it with links to project documents: https://dcwater.com/cleanrivers. Soapstone Creek and Broad Branch are not the focus of DC Water’s response to the 2005 consent decree or the amended 2016 version since they have separated sewer and storm systems and thus the sewage from those sewersheds does not overflow into Rock Creek regularly and intentionally. Possible leaks and illegal hookups in a MS4 system are very different from a CSO system where the system is designed to overflow. It is the CSO design that is being corrected- here and around the nation- by gray and/or green infrastructure. Language referring to the Piney Branch storage tunnel is on page 20 of the 2005 consent decree (which can be found on DC Water’s website) and in many places of the amended 2016 document.