Help Save the Gates Park Bridge!

Backcountry Horsemen of Montana now is the time to voice your support for a livestock-appropriate bridge across the North Fork of the Sun River at Gates Park. The Gates Park Bridge is on the US Forest Service's Schedule of Proposed Actions (SOPA) list for the Lewis and Clark National Forest (Page 11 of the following site): http://www.fs.fed.us/rl/lewisclark/projects/docs/3rd_2005-sopa.pdf

The Gates Park bridge decision will be based largely on three criteria: visitor use, cost and Wilderness Act guidelines.

While most wilderness bridges are inspected every four years, the structural issues of the Gates Park Bridge require a Forest Service engineer to inspect and evaluate its reliability on an annual basis. Although the bridge is currently safe for hikers and packstrings, there is concern that the sustained weight of heavy winter snows could further damage or even destroy the bridge. The structural challenges involving the Gates Park Bridge are three-fold:

The abutments, built in 1948, are formed from concrete and river cobbles which are too large and too smooth to be suitable aggregate for the cement to adhere properly. When struck, the cement breaks away easily from the cobbles. The abutments either need replacing or need to be reinforced and sealed in some manner.
Spring runoff and trail use eroded soil away from the "deadman" anchoring the support cable on the east end of the bridge. This spring Forest Service personnel backfilled the anchor as a temporary repair. According to a FS engineer in the Great Falls office, the anchors are technically too small for the potential sustained load of a heavy snow year.
The wooden substructure of the bridge is showing scouring or indents into the wood from wear. To rectify this, the substructure needs replacing and the bridge itself must be realigned.

With little to no federal funds available for trail work, the least expensive "fix" is to tear out the bridge. The estimated costs for the tentative Gates Park bridge proposals could range between $75 thousand and almost $300 thousand, especially since helicopters must be used to transport new bridge components or heavier repair materials and equipment. Following are the current suggestions:

Remove the extant bridge and reroute Trail 110 ¼ mile downstream to a natural ford, useable except during spring runoff. Projected cost: $75,000
Remove the extant bridge, reroute Trail 110 ¼ mile to a natural ford downstream from the current bridge and construct a new bridge across Moose Creek, six miles south of Gates Park. Projected cost: app. $130,000
Repair, and thus preserve, the current Gates Park Bridge with an estimated lifespan of 17 years; after 17 years, further maintenance would be required. Projected costs: $190,000 + $75,000 (at the 17-year mark) or $265,000
Remove the extant bridge and construct a completely new bridge of a higher construction standard and of an in-kind design which would accommodate a projected 50-year, snow-load lifespan. Projected cost: $266,000
Remove the extant bridge and construct a new bridge with a steel truss and/or a glue-laminate design with a projected lifespan of 75 years. Projected cost: $204,000
The default or no-action alternative proposal would be to continue monitoring the Gates Park bridge until it is deemed unsafe, closed to use and eventually removed.

The repair of the extant Gates Park bridge or the construction of a new bridge would be directly beneficial not only to Backcountry Horsemen but also to anyone who travels on foot or via livestock on Trail 110 through Gates Park for various reasons which could be stated in messages of support for the bridge.

The North Fork's extremely swift current can make fording the river difficult and dangerous even when the water is at its lowest level; depending upon spring runoff, the North Fork of the Sun is often impossible to ford at any point well into June. For horsemen—and hikers—passing through Gates Park late in the season, ice forming along the edges of the river could also pose a hazard to those attempting to cross at a ford. As a result, any options involving fording the river at Gates Park, Moose Creek or Circle Creek could be dangerous both to humans and to livestock. Because Gates Park is the northern gateway to trips along the Chinese Wall and sees heavy use from hikers through horsemen, it is beneficial for most forest users that a substantial bridge remain across the North Fork of the Sun River at Gates Park.

Considering private pack trips, outfitters, and hunting trips, surely forest visitors using livestock outnumber those on foot. However, most hikers do register as they enter the forest while few people using stock take the time to register from two to 15 people on each trip. As a result, the recorded data perhaps does not accurately underscore the need for saving the current Gates Park Bridge or for replacing it with a comparable structure. The recommended proposal, however, will include visitor use of the Gates Park Bridge gathered by Forest Service personnel monitoring that area of the wilderness.

As history, the 1948 Gates Park Bridge abutments are 56 years old and would ordinarily qualify the bridge for historic site consideration; however, the abutments comprise only 40 percent of the entire bridge so no assessments of their historicity are mandated by federal guidelines. The entire Gates Park administration site does qualify for the National Historical Register but has not yet been listed as such. To remove the Gates Park suspension bridge with its vintage "flavor" as an entrance to historical Gates Park could lessen the visitor's experience to the area from that particular historical point of view.

Any of the above proposals will impact both Forest Service funds and personnel. One estimate suggests that 30 head of stock would be needed for an entire summer to complete the repair or the construction of the bridge with three strings of pack animals and two Forest Service employees making alternating trips throughout the summer. As one FS employee and string would leave Gates Park, the other employee and another string would arrive; the third string would be resting. Considering the projected rigorous demands on FS personnel and livestock for the various proposals, perhaps the Backcountry Horsemen could volunteer time and stock to pack repair or replacement materials into Gates Park to provide the Forest Service stock-handlers and stock occasional relief?

Please address your comments in favor of repairing or replacing the Gates Park Bridge to the following Forest Service personnel:

Mr. Ian H. Bardwell

Gates Park Bridge Project SOPA Contact

Rocky Mountain Ranger District

P.O. Box 340

Choteau, MT 59422

Email: ianbardwell@fs.fed.us

Mr. Mike Munoz

District Ranger

Rocky Mountain Ranger District

P.O. Box 340

Choteau, MT 59422