Great Sand Dunes National Park
“Like a sea in storm,” exclaimed Zebulon Pike Jr. in 1807 when he first witnessed the immense Great Sand Dunes nestled in a dogleg crook of the Sangre de Cristo Mountains. From high above, in the toothed cirque of peaks surrounding the Crestone Needle, the dunes indeed appear as an unruly brown sea.
(page 2 of 4)
IN 2004, WHEN THE GREAT SAND DUNES National Monument was expanded into a national park and preserve, through a unique partnership between the Nature Conservancy and the U.S. Government, the new boundaries were stretched upstream to include the high peaks above the dunes where vital snow falls. Downwind, below the dunes, the park grew to include the “Baca,” former ranchland previously owned by water developers. The park increased four times in size and secured the watershed — the beating heart of the dune environment.
Once camp was ready, we doused Kian in sunscreen and walked to Medano Creek, the seasonal waterway that runs at the southern base of the dunes. No matter how many times I visit, I’m still stunned by the sheer volume of sand. I always used to wonder, “How did these immense dunes get here?”
People liked to say, “Mexico. The sand all blew in from the deserts of Mexico.” That seemed appropriate and romantic, like something so incredible could only come from a foreign place.
The truth is that the Earth sourced the sand locally, as volcanoes erupted then died, as lakes formed then dried, as Colorado heaved and faulted, as the San Juan Mountains started their slow grind from hard stone to dust, as the Sangre de Cristos eroded into the San Luis Valley below. Then the wind clutched this eroded detritus and spirited it away.
Geologists say that the San Luis Valley has looked basically the same as it does now for the last 6 million years. During that time, the wind has blown consistently out of the southwest, picking up slivers of earth and funneling it across the valley toward a low spot in the Sangre de Cristos — through three passes now known as Medano, Mosca and Music.
Upon reaching the mountains, the wind slows just enough that the dust and sand fall back to the ground, slowly forming the Great Sand Dunes. Six million years of slow and consistent effort, for humans it’s an immense amount of time, more than 500 times longer than we’ve even existed in the San Luis Valley. It’s this unfathomable time. Timelessness that draws me to these waves and mountains of sand. We reach Medano Creek and Kian wades straight in, shocked and then laughing wildly. It’s only knee deep on our 18-month-old son, though the waves that flow down the creek can suddenly reach his waist. He doesn’t even notice the waves.