GREAT SAND DUNES NATIONAL PARK– Fighting light pollution to preserve starry night skies and securing water flows amid climate changes are growing concerns at the Great Sand Dunes National Park and Preserve. 

It falls to Fred Bunch, the parks natural resources manager, to face these challenges. Bunch has been working at the dunes for the past 30 years. Visitor rates have skyrocketed. In 2017 a record 487,000 people visited, up from 230,481 visitors in 2013. Park official project a half million visitors this year. 

For the surrounding San Luis Valley, the dunes generate $29 million a year, economic activity supports 480,000 jobs. The revenue is essential to the valley.  

At the dunes, Bunch and his rangers increasingly take pride in the fact that it is one of the darkest locations on earth. The International Dark Sky Association may certify the dunes as an official location for seeing stars. The scale in which darkness is measured is arc magnitude per second squared out of a 23-point scale. The National Park is rated 22.  

Bunch said this a large reason why people come to visit the Park.  

Light pollution is a human impact on nature that can easily be fixed. Crews are installing downward facing lights, which do not project light up into the night sky. Park officials are also assessing options to use less powerful lights in the surrounding areas.  

At night coyotes howl, kangaroo rats escape from the clawing grasp of owls, and insects move across the sand dunes. This nightlife often is void of human disruption.  

The Great Sand Dunes National Park also faces water problems involving a neighboring ranch. 20% of annual flow is diverted up in Medano Creek across the Sante de Cristo mountains. On average, 4,000-acre feet of water runs into the dunes. About 1,000-acre feet a year is diverted for growing hay on the other side of the mountain range.  

Bunch said 2017 was the warmest year on record at the dunes as well as the wettest in the park. Due to the increased precipitation and mild fall weather in November and December, Medano Creek still flows through the dunes. The water from the creek incentivizes visitors to stay, Bunch said. People tend to stay for more of an extended period with the presence of water, he said. 

Water and the preservation of a dark night sky brings in revenue for the local economy. Without it 480,000 people could face economic difficulties.