Friday, August 31, 2018

The "Lancaster County's Historical Covered Bridges: Part I" Story

Neff's Mill Covered Bridge in Lancaster, County, PA
It was an ordinary day.  Walking across Neff's Mill Bridge, one of the 29 covered bridges that dot the landscape in Lancaster County, Pennsylvania.  The bridge is the oldest covered bridge in the county and carries traffic of all sorts across the Pequea Creek between West Lampeter and Strasburg townships.  It was constructed in 1824 and reconstructed in 1875.  Lancaster County owns and maintains the bridge which is known as the Pequea #7 Bridge.  It was referred to as a single span, wooden, double Burr arch trusses design with the addition of steel hanger rods.  The deck is made from oak planks and it is painted red with both approaches to it in the traditional white color.  It is supposedly the narrowest covered bridge in the county, being 11 feet, 7 inches wide and 11 feet high.  About three years ago I wrote a few stories on the covered bridges of Lancaster County and got several interesting comments from readers.  
This is Landis Mill Bridge near Park City Center.
It illustrates 
the use of Kingpost Truss construction.
Seems that quite a few people have never had the unusual chance to drive their vehicle across a wooden, covered bridge.  We that live in Lancaster County, Pennsyl- vania just take it for granted being that we have 29 of them in the county.  In the mid-1800s there were about 12,000 such bridges in the United States with close to 1,500 in Pennsylvania and 130 in Lancaster County.  That number has been greatly reduced nationwide due to various reasons.  
This is the Hunsicker Bridge in Manheim Township.
It illustrates the use of Burr Truss construction.
All of Lancaster's covered bridges are red except for Keller's Mill Bridge which is totally white in color.  All bridges are built using the Burr arch truss construction technique except for the Landis Mill bridge which is located a few hundred feet from Lancaster's Park City Shopping Center.  That particular bridge uses what is known as kingpost construction.  Mr. Elias McMellen takes credit for building many of the bridges in the county having built 12 of them, with only seven still standing.  Of the 29 that still remain, six no longer allow vehicle traffic to cross over them.  For those who have never traversed a wooden covered bridge, they are one lane wide, thus you must wait for visible traffic facing you on the bridge to exit before you attempt to enter.  If there are other cars in front of you, going the same direction over the bridge, it is best if you wait until the car in front of you is almost across the bridge before you follow them through the bridge.  The wooden bridges are sturdy, but may not be able to hold numerous cars at the same time.  
Willow's Bridge Covered Bridge in Lancaster County, 
Neff's Mill Bridge may be the oldest covered bridge in the county, but the newest covered bridge bridge is the Willow's Hill covered bridge constructed by the owner of Lancaster's Amish Farm & House tourist attraction in 1962.  It is known as The Willow's Bridge and was built from the remains of two previously closed wooden covered bridges.  Tomorrow I will take you along with me as I explore one of the bridges that was disassembled a few years ago and re-assembled at a different location.  It was another extraordinary day in the life of an ordinary guy. 



Burr Truss 
One of the earliest and most prominent bridge builders in our country was Theodore Burr from Torringford, Connecticut.  His truss design soon became one of the more frequently used systems. The Burr arch truss, as the design became known, used two long arches, resting on the abutments on either end, that typically sandwiched a multiple kingpost structure.
Kingpost Truss
The oldest truss design used in bridge construction, initially used under the roadway rather than above. It consists of a stringer, a Kingpost (vertical beam), and two diagonals and is used primarily for the short spans of approximately twenty to thirty feet.
     

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