I was giving a talk about hiking the White Mountain 4000 footers last year and one of the attendees asked me “How often should you update your maps?”
She asked me this question because several major trails in the White Mountains have been closed since Hurricanes Irene and Sandy tore up the trail system. The rain and flooding they caused washed out many bridges, closed roads, severely eroded some popular trails, and washed others away completely.
I hemmed and hawed about how it probably made sense to update them every 10 years ago, but I’ve been thinking about that question ever since, and I’ve come to a slightly different conclusion:
Plan each hike using as much information as you can, especially recent local information.
Most of the experienced hikers I know in New Hampshire do this already. We read recent trips reports that are digested by the trailsnh.com search engine or recent AT thru-hiker journals on trailjournals.com if we plan on doing a long section of the Appalachian Trail. Many of us belong to a forum called Views From the Top which is a wealth of local hiking intel and knowhow. We analyze the weather charts available from NOAA.gov and research historical temperature and precipitation information at Weatherspark. And because we’re from the area, we know about all of the trails that are washed out or were closed by the Forest Service after weather events. Unfortunately the Forest Service doesn’t publish most of these closings online – wish they made it more obvious – and you can sometimes only find the notice at the trailhead.
Compare that to hikers who just plan a hike using a map and a local guide book, even the publications from the Appalachian Mountain Club which are updated every couple of years. They’re out of date as soon as a weather event or an avalanche transforms the White Mountain landscape, a trail crew decides to re-route a historical trail to a more maintainable location, or remove a shelter to re-vegetate an overused area. The 1400+ miles of trail in the White Mountains are extremely dynamic and you simply can’t rely on maps or a guidebook for accurate information.
So, “How often should you update your maps?” is really the wrong question. We all should asking “What information sources do I need to plan a trip?”