For Review - Rehabilitate Tidal Basin and West Potomac Park Seawalls Environmental Assessment

The National Park Service (NPS) is inviting comments from the public on the proposed rehabilitation of the Tidal Basin and West Potomac Park seawalls. The public is invited to review the Environmental Assessment (EA) and share comments through April 5.  

In the years since their construction, the Tidal Basin and West Potomac Park seawalls have significantly settled and been compromised, leading to overtopping of the seawalls in some sections twice a day during normal tidal conditions and the water does not dissipate in a timely manner due to poor drainage.

Under the preferred alternative proposed in the EA, the NPS would:

-Rehabilitate approximately 6,800 linear feet of seawall along West Potomac Park and portions of the Tidal Basin to extend the seawall's life by approximately 100 years.

-Rebuild the seawall to include a pile-supported platform foundation that will prevent the seawall from settling and support height extensions of the wall if needed due to future rising sea levels or increasing storm surge elevations.  

-Increase the seawall height to 4.75 feet within the Tidal Basin and to 5.50 feet along West Potomac Park to account for wind and wave conditions along the Potomac River.

-Salvage and reuse stones from the historic wall in the rehabilitated seawalls.

-Repair, or replace, and widen walkways around the Tidal Basin from eight to twelve feet wide to provide smoother, more accessible connections to other pathways.

The planning and environmental compliance process for the proposed seawalls project is funded by the Great American Outdoors Act.  https://www.nps.gov/subjects/infrastructure/legacy-restoration-fund.htm

How to Get Involved:

Public participation is vital to the planning process. You are invited to review the proposal and provide comments and ideas from March 6 through April 5, 2023. If you prefer to mail your comments, make sure they are postmarked by April 5, 2023, to receive consideration - address is below. 

Document Content:

Appendix B: Agency Consultation   (5.5 MB, PDF file) Appendix A: Geotech Report   (32.3 MB, PDF file) Appendix F: Draft Section 106 Memorandum of Agreement   (2.5 MB, PDF file) Appendix C: Assessment of Effect Report   (68.3 MB, PDF file) Rehabilitate Tidal Basin and West Potomac Park Seawalls Environmental Assessment   (3.5 MB, PDF file) Appendix D and E: Existing Proposed Conditions and Construction Access Plans   (4.4 MB, PDF file) Disclaimer: Links within the above document(s) were valid as of the date published. Note: Some of the files may be in PDF format and can be viewed using the Adobe Acrobat Reader software. You may download a free copy of from Adobe Systems.