Last week, NPS and DDOT released the "Anacostia Riverwalk Trail Section 3 Realignment Draft Environmental Assessment" which covers the section of trail between Benning Road and the Maryland Boundary. The route of the trail remains unchanged since public scoping began last February.
The dashed green/yellow and green lines shows what will be built first as Phase I. The green and black line will be built after the completion of Comprehensive Environmental Response, Compensation, and Liabilities Act (CERCLA) remediation activities occurring at the existing Kenilworth Park South Landfill, which is currently closed to the public.
Most of the trail would 10-12 feet wide, with some 8 foot wide sections through Kenilworth Gardens and 14 foot wide boardwalks in wetland areas near New York Avenue. Along Hayes Street, parking would be removed and a barrier put in place on the street to create a 10 foot wide trail and a 4 foot wide barrier.
On one end of the spectrum, the trail would pass through the pristine Kenilworth Gardens Park and on the other it would pass over some landfills and past industrial areas with a sketchier environmental history. A site investigation will be needed for the area of NPS land surrounding the Benning Power Plant.
While it is unknown if that area contains any contamination, the trail through this segment would be constructed on top of the current grade, building the trail upward 1-2 feet (to be determined during construction) to prevent any soil disturbance. The shoulders of the path would be widened in this area, increasing the overall footprint but allowing for a gentle slope from the raised trail. At the conclusion of future remediation, if necessary, it is anticipated that the land surrounding the trail would be capped and built up to the same grade as the elevation of the trail in this location.
Even though the Kenilworth Park North Landfill is capped and open to the public, the section of trail going over that will also be built on 1-2 feet of fill to prevent any soil disturbance on top of the landfill. And, as mentioned above, the Kenilworth Park South Landfill will need to complete the CERCLA process before it will even be opened to the public. The feasibility study for this remediation is expected in 2012. Finally, a portion of the trail will be located on the edge of the NPS maintenance yard and the District Department of Public Works Trash Transfer Station.
The trail through Kenilworth would follow the current unpaved River Trail which would be paved and widened to 8 feet.
North of Kenilworth Aquatic Gardens the trail will go over Lower Beaverdam Creek on a new bridge and then under the Amtrak Railroad and New York Avenue bridges. The trail in this area would go along the Anacostia River bank on an elevated boardwalk so as to minimize impacts on the wetlands and vegetation. The proposed trail in this area would be 12 feet wide and the proposed boardwalk sections would be 14 feet wide to accommodate railings.
One improvement since February is that the bridge across the Anacostia has been moved from Phase II to Phase I (though in the background section it is still listed as being in Phase II). The bridge will be 390 feet long and connect to 1000 feet of trail on the western bank of the river where it would connect to an existing gravel service road that connects to the National Arboretum. During the normal operating hours of the National Arboretum (open every day from 8 a.m. to 4:30 p.m.; closed December 25), users of the trail could pass through the Arboretum and exit at the R Street Gate.
Two bridge designs are under consideration.
A girder bridge is the most common bridge type for similar uses. Either steel or concrete could be used. The second option would be a prefabricated steel truss bridge, which would be prefabricated by a manufacturer and then assembled on site.
In addition, a small dock (approximately 12-foot by 12-foot) would be installed in the area of the proposed bridge.
The trail on the western bank would be built at grade, with a 10-foot-wide asphalt trail and 2-foot stone dust shoulders. The proposed bridge would be 14 feet wide to allow two-way bicycle traffic with a buffer to accommodate pedestrians or bystanders on the bridge.
Phase II will also be 10-12 feet wide and will include a small bridge over Watts Branch.
I prefer the new alignment to the original one in yellow on the map above, and I'm glad to see that they moved the river crossing into Phase I as that will be a real asset to trail users. But I'd like to see them keep the original proposed trail from south of the Amtrak tracks to the north end of Anacostia Ave NE - the northernmost section of the yellow line - as a Phase III. Without it, residents of Kenilworth heading north to Maryland will first need to go south to the Kenilworth Recreation Center.
Comments are being accepted until the end of January, 2012.