Pictures and Story by Larry Gomes
A crew of three volunteers showed up to finish off our tenth day of trail work for the 2012 season. The day started with a trip out to Corridor 11 to figure out what to do with a bridge that had fallen off one of its banks. When the crew arrived they looked under the bridge and found out that at least 3 of the beams had fallen onto rocks that were keeping it out of the water and giving it support.
After some discussion, they decided it would be better to leave the bridge in its current position and use logs to create a ramp from the bridge deck up to the top of the bank. This would allow sleds and the groomer to cross the bridge without hitting the bank. After a couple of passes with the groomer, the bridge would be filled in with snow making a smooth trail across it.
This bridge on Corridor 11
dropped off the banking and into the river bed. The solution for now was
to use logs to build a ramp that
allows sleds and the groomer to easily get up onto the bank from the bridge deck. It does not look like much of a problem
in this picture, but the height of the bank above the bridge deck on the right side is about two feet.
As the crew was heading out from this job, they spotted a section of Corridor 11 along the pipeline that looked flooded. Upon further investigation, they found 2 plugged culverts and 2 plugged bridges that looked like they had the remnants of beaver activity. This area had been cleared of beavers two years ago and it looked like one or two beavers had come back sometime during the summer, but then they must have left the area because the dams were not in very good condition. It took the crew about an hour to clear the bridges and culverts and that should stop the flooding across this trail.
The group then continued on to PT109 where they started a detailed bridge inspection. When this trail was first opened back in 2003, the club used hemlock for several of the bridges. These bridges are now nearing their end of life and the club wanted to know when they would need to be replaced.
The crew each focused on separate tasks at each
bridge. Carl Bull, took on the task of checking the deck for rot using an
awl. Eric Johnson got under each bridge and inspected the beams to make
sure they were safe and Larry Gomes logged each bridge location into a GPS and
took detailed notes on the condition and size of each bridge. A total of
six bridges were inspected and all but one bridge should last another two years.
One bridge that failed the inspection will be replaced next year and the
remaining bridges will be replaced as they near their end of life.
Eric Johnson (on the left)
checks the beams under this bridge while Carl Bull (on the right) checks the
deck for rot. Most of these
hemlock bridge decks are in pretty good shape considering they are 9 years old. We think they have survived longer than some of
our other hemlock bridges because this section of trail is heavily wooded and this keeps the hemlock moist. When these bridge decks
are replaced, the club will use pressure treated lumber which will last between 20 and 25 years instead of the 7-10 year life expectancy for hemlock.
Even though pressure treated lumber is more expensive up front ($1.40/foot vs. $1.00/foot for 4" x 6" x 14'), it is more cost effective in the long run
because it can last up to 3 times as long saving money on lumber, trucking and disposal costs as well as reducing the toll on our volunteers.
During the trip up the PT109, the crew found another section of trail that was flooded due to a beaver dam under a bridge. This was another case of a dam that looked like it had been built earlier in the summer, but then abandoned. The crew was able to breach this dam and lower the water level so it was no longer flooding the trail. The last project of the day was the dismantling of a new beaver dam that had been found last week when the crew was installing a bridge. This dam was an active beaver site and so a trapper had been brought in to catch the beavers in this area. This was a fairly large dam that extended along the trail for about 150 feet. The crew breached this dam in 3 places and dropped the water level below the trail before heading home.
On Sunday, Larry and Carl inspected another hemlock bridge on Corridor 19 that is scheduled for re-decking next year. This bridge was in much worse shape then we expected with several holes that must be repaired before the snow flies. We are keeping our fingers crossed that this bridge will hold together for this season.
This is one of several holes in
the deck of an old hemlock bridge on Corridor 19 north just north of State
The club will patch these holes and hope for the best this coming winter. This bridge is scheduled for re-decking next year.
We would like to thank the three volunteers who came out this past weekend to help with these projects. We will begin our 2013 trail work in the spring after the trails close.