I'm a veteran, a mother, and an American citizen; public lands hold a sacred place in my life.

When my friend, a Marine, was killed in Afghanistan, I drove up to Gettysburg National Military Park and walked by myself for hours. As I stood on the grounds of one of the most pivotal battles in American history, I celebrated the life of my friend and honored the sacrifices he and so many others in uniform have made.

Public lands enshrine the natural wonder of this country.  Forests, rivers, mountains, valleys — this is the romantic magic of the "America the Beautiful" that I fell in love with as a kid.  And they're a big part of my patriotism today.

Many of these lands have been protected and conserved by the Land and Water Conservation Fund (LWCF), a bi-partisan program founded in 1964 to safeguard natural areas and to ensure all Americans have access to these spaces. The LWCF receives its funding from royalties paid by oil and gas companies, so it costs the taxpayers nothing.

Here's the problem: The program expires on Sept. 30,  after 53 years of outstanding service to the American public. Public lands give Americans a place to connect with their families, their country, and their fellow citizens. I fear that so many of us have taken these spaces for granted.

LWCF does not just protect public lands and parks, but funds local projects and veterans' memorials, too. Throughout Pennsylvania, LWCF has granted $309 million to protect public spaces. In Montgomery County, my new home since leaving active duty, there are 49 pools, parks, or playgrounds that have been supported by LWCF since its founding.  This includes Valley Forge National Historical Park, a favorite of my family's. More recently, LWCF contributed $10 million to protect the "Field of Honor" and the Flight 93 National Memorial to honor the brave heroes of Flight 93 in Shanksville, Pa.

I ultimately made my decision to join the military with the hills of Virgin Islands National Park on the horizon.  I told my parents that I was joining the Navy in Rocky Mountain National Park in Colorado. In the weeks leading up to my initial officer training, nervous about the adventure ahead, I went on a trip with my mom, seeking the peace and calm that comes from nature; we wandered Muir Woods National Monument in California and talked about the choice I was making.

I spent four years on sea duty as a surface warfare officer aboard a guided missile cruiser based in Norfolk, Va.  I deployed to the Arabian Gulf, chased pirates in the Indian Ocean, and spent more than 300 days at sea, war-gaming in the Atlantic. During and after my tour of sea duty, public lands were critical to maintaining my connection to the country I had promised to serve.  Hiking Virginia's Shenandoah National Park was an escape from the fast pace of our operations and a needed reprieve from the sterile gray walls and incessant electrical hum I lived with aboard the ship.

Inspired by the hard-fought battles of previous generations, I speak out today because I know I must fight to protect our natural heritage.

That's why I call on Sen. Bob Casey and the rest of the Pennsylvania delegation to fight to permanently reauthorize and fully fund the LWCF before it expires at the end of September, without a guarantee for future funding.  Thousands of spaces and community projects are at risk. I have been fortunate in my life, and in my service, to find solace, peace, and clarity in protected public lands. It is only right to protect those spaces for future generations.

Both as a veteran and mother, I have a duty to protect these public lands for my 1-year-old daughter, whose eyes light up when I say the word "tree."  She points at their trunks and grabs for their green leaves. I want her to have the chance to hike and play in the public lands as I did as a child. Her generation should not miss out on those monumental experiences and the natural beauty that this country promises.

Arielle Griffin joined the Navy in 2011 where she spent seven years on active duty. She is currently a lieutenant in the U.S. Navy Reserves and resides in King of Prussia with her husband and daughter.