The post below was sent as an issue of my newsletter, Ready for Rain.
I’ve planted trees like Japanese maples and fast-growing conifers at every house I’ve owned. I think of them as semi-permanent fixtures that slowly improve the property and provide shade, privacy, and beauty.
Soon after getting our property on Orcas, I was motivated to start planting and picked up a couple of Leyland Cypress from a nursery in our area. With the trees in tow, I made my way to the south property line with a shovel, thinking I would dig a couple of nice big holes for the trees. In a familiar move, I put the tip of the shovel into the dirt and then pounced on it with enough force to dig through the soil. This action, surprisingly, didn’t work. Instead, the shovel went in a few inches and hit an impenetrable force that made the shovel vibrate in my hand. I tried again and the THUD sound it made was deep and resonant.
I had to regroup. The locations I had plotted for the trees were all solid rock. Thud. Thud. Thud. So, I started probing and eventually found a couple of spots with softness, or at least enough to get a tree in the ground. The cypress ended up being planted on rock, but with enough soil around them to stand straight.
With the planting complete, I got curious and walked around the property with a long piece of rebar tapping through the thin soil. Almost every bit of space around the Yurt was covered in a thin layer of soil and then, cold, hard, rock.
Our property is not alone in this experience. Orcas is sometimes referred to as “rock island” and that name has become part of the local culture. Our internet service provider is called Rock Island Communications. It’s just a fact of life on the island that manifests in strange and interesting ways.
In between our building site and the water is a tall Douglas fir tree that has clearly broken in half. Halfway up the trunk, it just stops in a jagged point. I’ve seen this in multiple places around the island and eventually asked the arborist what was happening. He said that the roots of some trees get anchored into the rock over time. When the wind blows and something needs to give, the trees break in half rather than fall over. I couldn’t help but think of my little cypresses slowing anchoring themselves into rock that will be their foundation for many years.
I found this fascinating and started to learn about the geological history of the San Juan Islands and what made Orcas into rock island. The short answer is glaciers. In the last ice age (between 10,000 and 18,000 years ago), a huge glacier came down from Canada and covered our area in slow moving ice that was nearly a mile thick. The weight and pressure of the glacier pushed everything but the most stubborn land southward. Orcas was a piece of rock that resisted the flow of the glacier.
Today you can see evidence of the glaciers in large boulders that seem to be randomly dropped around the island. These rocks are called “glacial erratics”. They traveled in glacial ice for hundreds of miles before being deposited in locations where they remain today. I think of them as travelers from an ancient era that moved through the northwest when woolly mammoths and mastodons likely roamed Washington.
In other parts of the Salish Sea, where the glaciers left piles of sand and ground-up rock, homes by the shore are in danger as the sea slowly erodes their property. When we first visited the Yurt and looked at the steep hill from the house down to the water, erosion was on our minds. We soon discovered that it was not a problem for our property. It’s made of rock that withstood the force of glaciers. It isn’t going anywhere.
Owning property made of rock is one thing. Building a new house on a rock is another. As Drew and John, our architect, reminded us, once the house is built, it will be locked into bedrock.
Once the demolition was complete and the trees were removed, we could move to excavation, which meant, for the most part, using 30,000lb machines to break big rocks into smaller rocks. This phase was where the project became very real. Once expensive holes were dug, the house’s location would be locked-in.
To make sure everything was right, we had multiple surveys done that pinpointed the corners of the house using GPS and computerized survey equipment. For the first time, we could see the footprint of the house and get a feel for its orientation. The house is mostly right angles and any east/west line should point directly at the view. After an initial survey, we moved the house a few feet and changed its orientation a couple of degrees.
A problem for the surveyors was trying to use stakes on a rocky surface. In some places, they had to pile rocks around a stake to make it stand upright.
With all the locations double and triple checked, the real work could begin. Excavators got to work digging out the crawl space for the house and creating holes in the rock for post foundations.
This work is mostly done with a rock hammer that attaches to the tip of the excavator arm. It breaks the rock before the excavator comes back with the bucket to dig it out and remove it.
Breaking rocks is both time consuming and incredibly loud. For hours a day over a few weeks, the excavators hammered away.
My little cypress at the edge of the property looked so quaint in the midst of the incredible noise echoing through the neighborhood. We checked in with the neighbors from time-to-time. Maybe one more week, we’d say, with a hopeful smile. They’ve built houses on rock island. They know how it goes.
After a month or so, the excavation was complete and the property was transformed into level sections for the crawl space and garage. Holes that will support steel posts were carved into the rock on the western slope.
I don’t think either of us want to go through that kind of excavation again. We could hear the constant rock hammering from the guest house and could only imagine what it was like to live next to it.
But for all the noise and work, we get a building site that’s practically bulletproof. Our house will be anchored into rock so hard that a glacier couldn’t move it. And for a house that we consider our forever house, that sounds about right.
YouTube Highlights – The Excavation
The Ready for Rain YouTube channel is the home of short videos from the building project that are organized into playlists. The videos below are from the Excavation playlist.
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