This Popular Trail At Zion National Park Gets Closed Down Constantly. Here's Why

Zion National Park, located in Southwestern Utah, is full of incredible hikes and bright orange canyons, making it one of those national parks that everyone should put on their bucket list. However, like many wild places, behind all the beauty of Zion lies some danger. In fact, besides the animals you need to beware of when adventuring in Zion, one of the park's most popular trails — the Narrows — is often closed down temporarily for a different reason. This trail in Zion is particularly unique because it takes hikers wading through the Virgin River as they explore the bright orange and narrow passageways of one of the park's famous slot canyons, making for a different and exciting experience. However, the Narrows are sometimes dangerous.

The first safety concern with the Narrows has to do with toxic algae that sometimes blooms in the river. This algae can be life-threatening if consumed which is one of the reasons why dogs are not allowed at Zion; however, while the National Park Service typically releases a public health warning during algae blooms, they don't always close the trail. The reason why the NPS often closes the Narrows is due to the risk of flash floods. 

Before heading into Zion to hike in the Narrows it is important to check the NPS website for current trail conditions and closures as well as stop by the Visitor's Center to ask for information on water levels. The NPS typically closes the Narrows when the river speed rises above 150 cubic feet per second. It is also important to check weather reports because, although it may not be raining in Zion, rain miles from the canyon can also cause flash floods and dangerous conditions.

You can also assess the risk of hiking the Narrows on any given day by looking at the Flash Flood Risk sign that is posted at the beginning of the trail which ranges from green (meaning floods are not expected) to red (meaning that flash flooding is likely and expected). Furthermore, the Narrows are most likely to be closed in the spring when the snow melt joins the river and causes high water levels. In 2024, the Narrows hike was closed from April 8 to June 19, which was the second-longest closure in the trail's history according to the Salt Lake Tribune. While flood closures are rarer in the summer and fall, the NPS warns that sudden rains can cause temporary closures at any time.