Thursday, March 5, 2015

Less than a year later

Less than a year later and with Norman's help we organized the first DSWAC 'pack horse' dry stone bridge building workshop in Canada. A handful of enthusiastic stone aficionados signed up for the course a couple months before the event ( at 100 dollars for three days hands-on instruction ) and together that October we made bridge building history at 
Port Hope Ontario's first Canadian Dry Stone Wall Festival.

The property I had chosen to build the bridge on was in the town my family and I had just recently moved to. There was a good bed and breakfast there off main street that had a beautiful 4 acre property with a gentle swale going through a grassy clearing near the huge Victorian house. I made a scary cold call and proposed the idea of having a bridge built there to the owner who I had never met. He was was not as surprised or as cautious as I had been expecting. Instead he listened intently and was quite enthusiastic as I told him I had chosen his property for a very unusual stone project. When I inquired whether he would object to the idea of me constructing a traditional Scottish style dry stone bridge somewhere on his estate, at a cost to him of only the twenty four tons of stone material, he replied "Am I an idiot? " Which I took to mean that he was all for it.

As the days got closer he got more and more enthusiastic about the free bridge he was going to get and offered to serve lunches to everyone who would be working on the project.

Before the three day public event during which I hoped to complete the bridge, a fair amount of prep work had to be done. Enough suitable stone material had to be procured. This was coming from a stone quarry I had recently discovered about an hour away. 

The foundation holes had to be dug and the abutments built up to the height of finished grade either side of the creek we were planning to span. Holes are usually not much fun to dig but these were. The excitement of what we were going to be creating was mounting by the shovel full. It was a hot day and shirts came off almost immediately. 

The 6 by 4 foot squares had to be dug to below the creek bed, which fortunately was not flowing during that uncomfortably hot week back in late September 2004. Large limestone slaps, similar, but slightly smaller than the squarish huge chunks of armour stone used by landscapers, were lowered into the holes and fitted in a dove tail fashion to create a kind of dry stone crib below grade. From these bases there would be support to spring the bridge off of. 

These two 'abutments' had to be low enough to not move with the frost.

My hope was that if they did move at all they would both move the same amount and at the same time and in the same direction so that the bridge would still stay tight. 

This bridge was to be an experiment. I needed to see if dry laying stone was a suitable method for building small foot bridges in Canada. I had already by that time built many smaller dry stone garden arches and realized that as long as the matching bases were dug evenly, with the same size and depth of footprint into similarly undisturbed ground, over time, very little evidence of conflicting movement occurred across the arches. Would a dry stone bridge have the same success? 

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