A group of volunteers organized by a local nonprofit and an Alaska Native corporation installed about one-quarter mile of new surface on the Portage Trail, which crosses boggy wetlands between Larsen Bay and the Karluk River.

Volunteers added Geoblock paving tiles to a section of trail near the river, beginning at a riverside stretch where the product was installed two years ago. Geoblock is a paving surface made of polyethylene with large holes to allow vegetation to grow through. The tiles have become a popular tool to prevent wetland trails from turning to soupy mudbogs, partly because the tiles require less maintenance than board walks on pillars.

“The trail is an important trail for the residents and for visitors to Larsen Bay,” Erin Whipple, assistant land manager at Koniag Inc., said.

“Not only is it a subsistence trail, but it is used for recreation and to support some of the guiding activities out of Larsen Bay. Several of the lodges will bring people over from Larsen Bay to the Karluk River using Argos or four-wheelers, instead of flying them in,” Whipple said.

Koniag owns the land travelers cross when they use Portage Trail. The corporation can be reimbursed for some of the money it spent on the trail project through a conservation program run by the U.S. Department of Agriculture, Whipple said.

Kodiak-based nonprofit Island Trails Network also participated, donating labor and spending part of a $10,000 grant it received from the off-road vehicle manufacturer Polaris.

Like many lowland trails in Alaska, erosion to Portage Trail is exacerbated by increased traffic in recent years. As the trail is pushed down by the weight of hiking boots and four-wheelers, muddy spots develop that hold water instead of allowing it to drain.

When people come to a muddy spot, they generally skirt it, so the muddy spot gets wider, creating an effect trail designers call “braiding,” that looks similar to a braided stream.

“That is a sign of continued use over a trail that cannot sustain the use. As one hole gets boggy, people tend to drift over to another area with more of a vegetation base,” Whipple said. “It is inevitable until you either harden it or reroute it to another area.”

Rerouting Portage Trail was not a good option because the lowlands are so expansive. Travelers naturally want to take a direct route to the river and aren’t likely to follow a new, miles-longer, route.

Whipple submitted photographic evidence that Geoblock works, at least to the extent that the tiles allow vegetation to survive on the trail. The photos show the trail in 2005 when Geoblock was first installed on the Karluk’s bank and the same section of trail in a picture taken last week.

The 2005 photo shows Geoblock laid next to a soupy trench. The second shows volunteers walking on a hard surface of trampled grass with Geoblock supporting them underneath and no mud in sight.

“Eventually you do not even see the plastic any longer, so we are going to work on marking the trail because of that,” Whipple said.

Mirror writer Scott Christiansen can be reached via e-mail at schristiansen@kodiakdailymirror.com.