Project (7214) Document or Notice Agency Seeking Comment/ Posting Notice Date Posted Closing Date
National Zoological Park General Services Building and North Road Retaining Wall Environmental Assessment

Environmental Assessment
[PDF 7.1 MB]

The Smithsonian Institution / National Capital Planning Commission
January 25, 2012 February 24, 2012
Description of Project

The Smithsonian Intuition, with NCPC as lead federal agency and the National Park Service as a cooperation agency, has prepared an Environmental Assessment (EA) to examine the environmental impacts of the construction of a retaining wall between the General Services Building and North Road on the National Zoological Park. The purpose of the project is to structurally stabilize the General Services Building and remove existing hillside loads from the building.

The EA includes four alternatives, one no action alternative and three action alternatives. Action A, the no action alternative, analyzes the continued current management operations and conditions. Alternative B, the straight wall design, analyzes a straight retaining wall, approximately 945 feet in length that varies in height from approximately 40 feet tall on the west to an at grade tie-in on the east end. Alternative C, the soil berm design, includes the construction of a straight retaining wall, similar to Alternative B; however, Alternative C includes soil berms in order to minimize the visible height and length of the proposed wall. Alternative D, the terraces design, would include the construction of a straight retaining wall as well as multiple terraces to break-up the visual mass of a single retaining wall.

The EA also evaluates two alternatives to the conditions of North Road, a road on the Zoo property. Option 1 would provide approximately 3.5 feet of planning between a proposed retaining wall and the future expansion North Road. Option 2 would provide up to 13 feet of planning area between the future roadway expansion and a retaining wall.

Input Requested
The public has the opportunity to comment on the proposed alternatives and potential impacts outlined in the Environmental Assessment.

Submit Comments to:
ZooRetainingWall@g-and-o.com

- Or to -

Zoo Retaining Wall Comments
c/o Greenhorne & O’Mara
810 Gleneagles Court, Suite 106
Baltimore, MD 21286

Commission Action Requested
Approval of site plans

Expected Date of NCPC Action
Early Summer 2012

Historic Preservation (section 106) Consultation Process
Section 106 review is ongoing. The Smithsonian Institution is also using the Environmental Assessment public review to allow interested parties to comment on the cultural resources concerns and the No Adverse Effect determination.
Other Information
A hard copy of the Environmental Assessment is located at the NCPC’s office: 401 9th Street, NW, Suite 500, Washington, DC.

NCPC Staff Contact:
Cheryl Kelly
202.482.7291
Cheryl.Kelly@ncpc.gov