A half-century-old preservation program that has funded city parks and playgrounds, mountain bike and hiking trails, rock climbing areas, and other public land projects is set to expire at the end of September.

That is, unless Congress reauthorizes the Land and Water Conservation Fund (LWCF).

This is the second time the fund is at stake, after it was allowed to expire but was temporarily reauthorized for three years in 2015.

Outdoor Industry Association (OIA) is urging outdoorists and business owners to send their senators and representatives in Congress an email telling them why the fund is so important to recreation and directly fuels their businesses.

Arm yourself with information: Outdoor Recreation Economy reports for all 435 congressional districts

For 53 years, a small portion of federal leasing revenues from offshore energy development has been reinvested to protect and conserve public lands in and around national parks, forests, monuments, and refuges, as well as state and local programs.

The fund is fed by a percentage of more than $6.7 million in annual offshore oil and gas lease revenue, according to OIA. 

Earlier this year, the Trump Administration allotted $425 million to the fund, but Interior Secretary Ryan Zinke has proposed to reduce funding to about $8 million. The maximum allotment is $900 million.

Businesses and individuals can sign a letter of support for the fund. It reads: 

Each year, the outdoor industry supports more than 7.6 million American jobs, generates $887 billion in direct consumer spending, and contributes $125 billion in federal, state and local taxes. To maintain this growth, our businesses depend on access to the nation’s lands and waters and certainty that LWCF investments will continue to be realized in these places.

Full and dedicated funding for LWCF will enable communities across the nation to invest in the outdoor economy, create jobs and support rural communities looking to diversify their economies. The Land and Water Conservation Fund makes investments in our shared outdoor heritage—from backyards to the backcountry—that are essential to outdoor companies, our consumers and the health and vitality of urban and rural communities.

There are 33 days left.