A hike through the Narrows requires hiking in the Virgin River. You must get your feet wet since there is no trail. The depth of the water and strength of the current varies and there is always a possibility for the trip to be canceled due to flash flooding (this is a rare occurrence and your guides are able to anticipate any possibility by watching any change of precipitation).
Sturdy footwear is essential. Hiking boots with good ankle support are best. Sandals and bare feet are not appropriate. Make sure you bring quick dry clothes! It is a good idea to waterproof all of your belongings with dry bags. Smaller resealable bags provide extra protection for cameras and other valuables.
Water level fluctuates greatly from year to year and day to day depending on many factors. Walking is usually moderately difficult, with knee deep crossings on the slippery and uneven river bottom with frequent pools up to waist deep. When the current goes up, walking against the current becomes challenging and crossings of mid-thigh deep are frequent with pools that can be chest deep.