Our nation’s cities are experiencing a renaissance.

Since 2000, the number of young, educated adults moving to central urban neighborhoods has increased by nearly 40 percent. This has placed renewed focus on the value of city parks, trails and waterways.

A city’s natural assets are vital urban centerpieces. They foster economic growth, anchor vibrant neighborhoods and provide space for healthy physical activity and alternative transportation. Nearby parks and open space are proven to attract residents and businesses alike. In many cases, smartly planned park systems have ushered in urban revitalization.

The Land and Water Conservation Fund has been an essential engine for that revitalization. This program, authorized by Congress in 1964, has effectively used federal matching grants to catalyze public and private local investments in our parks. These investments, in turn, have yielded exponential economic and quality of life improvements in cities across the country.

If Congress does not act to reauthorize the LWCF before September 2015, it will expire, putting park projects across the country at risk.

As the mayors of Fort Worth, Texas, and Denver, we see firsthand how our people treasure our parks, open space and trails. The LWCF has been a dynamic resource. In Denver, $1.2 million in federal grants for the South Platte River, which winds its way through the heart of the city, led to more than $2.5 billion in local public and private funding. That’s $2,000 in local funding for every federal dollar invested in the area. As a result, Confluence Park on the river has played a key role in the revitalization of Denver’s downtown.

In Fort Worth, an initial LWCF grant of $725,000 enabled the purchase of 325 acres to create Gateway Park. Since then, an additional $4.8 million has been committed by state and local sources to double the park’s size. Gateway Park hosts athletic tournaments each year involving out-of-town teams, bringing $5.5 million annually to the local economy.

Our cities are success stories, but they aren’t unique. Cities such as Philadelphia; Nashville, Tenn.; Salt Lake City; Scottsdale, Ariz.; Greenville, S.C. and many others have developed thriving urban parks thanks to initial LWCF matching grants that led the way for local public and private investments that fuelled economic and cultural revitalization in neighborhoods close to the urban core.

These outdoor projects — and the economic growth they spur — would not be possible without LWCF funding. Over the fund’s 50-year history, it has provided more than 42,000 matching grants, totaling more than $4 billion, supporting park projects in more than 98 percent of American counties. The LWCF also plays an important role in increasing opportunities for outdoor recreation outside many cities by improving access to our national public lands.

This vital program is fully funded by offshore oil and gas royalties. Originally, the federal offshore energy receipts were specifically set aside to protect America’s lands, water and outdoor recreation resources. Today, while these receipts send more than $9 billion each year to the Treasury, only $900 million — less than 10 percent of the total — is authorized for LWCF usage. Typically, Congress diverts much of the authorized funding, reducing the investment in parks.

As co-chairmen of Mayors for Parks, a bipartisan coalition of nearly 40 American mayors, we are pressing for the reauthorization and full funding of the Land and Water Conservation Fund. We are also concerned about the amount of LWCF funding that goes to urban parks. To date, less than 2 percent of all LWCF funding has been spent on projects in our 100 largest cities. A greater urban emphasis would yield remarkable benefits.

In June 2014, the U.S. Conference of Mayors unanimously passed a resolution supporting LWCF reauthorization and full funding. This is a program supported by hundreds of mayors from both parties, from large and small cities, and from all of the regions of our country.

Parks are the quintessential home of American recreation. In cities, they have outsized impact. Parks make our neighborhoods more desirable. They promote exercise and encourage a healthy lifestyle. Parks and green spaces even help cities manage storm water drainage.

We call on Congress to reauthorize funding for the Land and Water Conservation Fund and preserve this vital resource for our parks with public policy that has yielded a tangible return on investment several times over.

Betsy Price is the mayor of Fort Worth, Texas; Michael B. Hancock is the mayor of Denver. They are co-chairmen of Mayors for Parks.

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