The retaining walls along the Jefferson Memorial’s tidal basin are breached by water twice a day and have sunk as much as eight inches in recent years. The soil along the great lawn stretching away from the Capitol is so densely packed in some areas that it’s thicker than concrete, making it impossible to grow new grass. And the reflecting pool has become a stagnant health hazard, filled with bacteria and dead fowl.

Despite the decay, the National Mall is still literally and figuratively “America’s front yard— and is host to upward of 25 million visitors every year — more than Yellowstone, Yosemite and the Grand Canyon combined.

That’s why the Trust for the National Mall — a public-private nonprofit launched in 2007 by then-Secretary of the Interior Dirk Kempthorne — is fighting hard in tandem with the National Park Service to preserve the space as one of America’s lasting cultural landmarks.

“We encourage all Americans to be involved in the future planning of the National Mall,— said Caroline Cunningham, president of the Trust.

Buoyed in part by a renewed focus on the national parks inspired by documentary filmmaker Ken Burns’ six-part series currently running on PBS, Cunningham noted that the Mall continues to play an important role. “The national parks were always viewed as a way for the American public to experience their country,— she said. “And the National Mall is key to understanding the history of this country.—

Still, the task of preservation is complicated by numerous problems — in addition to the physical damage to the park, it is estimated that the Mall needs more than $400 million dollars worth of deferred maintenance. The main areas of concern in any renewal, Cunningham said, involve keeping the space available for large-scale demonstrations and festivals while still maintaining the beauty and upkeep of a heavily trafficked urban green space.

“It was never designed for the volume of visitors that come each year,— she said.

Surprisingly, damage to the Mall during the historic 2009 inauguration ceremony was kept to a minimum, Cunningham said. “The grass is in such poor condition that having that volume really didn’t hurt it any more than it was already damaged,— she said.

The Mall has already received some attention from the Obama administration. Though House Democrats stripped more than $200 million in funding earmarked for the Mall from the February 2009 stimulus bill, Secretary of the Interior Ken Salazar announced in April that the department would spend $55 million of its own stimulus appropriations toward Mall restoration.

According to Bill Line, a spokesman for the NPS, $30.5 million of the funds are geared toward figuring out how to avoid stagnation and establish recirculating water in the reflecting pool. Further, the Jefferson Memorial seawall and the District of Columbia War Memorial will receive much-needed maintenance.

The National Mall Plan — a document in the process of being prepared by the NPS — will outline a vision for the future of the space. A draft is due out in November, and the NPS will seek public comments on the draft and the final plan in forums across the country. No timetable has been set for final approval of the document.

“Ultimately what the National Mall Plan will evolve into is a planning document that will give the National Park Service guidance for how the National Mall will be managed for the next 30 to 40 years,— Line said.

Some ideas being considered include a park ranger station at the Smithsonian Metro station, expanded restaurant choices and more restroom access.

Still, Line is careful to emphasize funding for any proposed initiatives will still need to go through the typical legislative appropriations process.

“We are continuing to work with the administration and Congress to ensure that they help with deferred maintenance costs,— Cunningham said.