National Mall and Memorial Parks begins process to repair Tidal Basin and West Potomac Park seawalls

News Release Date: June 29, 2022

WASHINGTON – National Mall and Memorial Parks has started planning for the first phase of a massive, proposed project to repair the seawalls and iconic shoreline landscape along the Tidal Basin and West Potomac Park. Funded by the Great American Outdoors Act, a $5.7 million contract was recently awarded to begin the planning and compliance process.

“The seawalls are a critical component to protecting the longevity of our nation’s treasures, such as the Thomas Jefferson and Franklin Delano Roosevelt memorials,” said National Mall and Memorial Parks Superintendent Jeff Reinbold. “By incorporating climate resiliency measures into the design of the seawalls, we’ll ensure these special places are protected for generations to come.”

Age, high water and poor drainage have taken a toll on the walls. Despite various repairs over the decades since their original construction, the seawall systems are no longer structurally sound and threaten the historic setting and visitor safety. Without improvements, the walls will continue to deteriorate and fail which will lead to walkways buckling and soil eroding.

The proposed project would address significant high priority deferred maintenance and repair needs in the park while improving accessibility, safety, and the ability to preserve, protect, and foster appreciation of the iconic memorials and landscapes. It is anticipated that a design-build contract will be awarded in late summer of 2023 or early 2024.

Portions of the failing Tidal Basin seawall north and south of the inlet bridge, as well as part of the West Potomac Park seawall, will be reconstructed using modern concrete and stone veneer technology that will increase durability and maintain the historic character. Where possible, the original stone masonry will be repurposed and reused. The sidewalk on top of the seawall along the Tidal Basin will be replaced and regraded to provide smoother, more accessible connections to other pathways. Rehabilitation of the adjacent landscaping will provide proper drainage for the area. New, stronger foundations will be able to support height extensions of the wall if it is needed due to future rising sea levels or increasing storm surge elevations.

The repairs will also decrease the amount of time spent by National Park Service staff on reactive maintenance duties such as debris clean-up caused by the high tides that routinely flow over the existing walls, the need to monitor and fence for safety purposes the subsiding walkways atop the wall, and replacement of cherry blossom trees that suffer poor health or die when their root systems are over-saturated by high tide waters.  

The Great American Outdoors Act is part of a concerted effort to address the extensive deferred maintenance and repair backlog in public lands. Supported by revenue from energy development, the fund provides up to $1.3 billion per year for five years to make significant enhancements in national parks to ensure their preservation and provide opportunities for recreation, education and enjoyment for current and future visitors.
 

 NPS