Once upon a time, in the dark ages of Gabriola (that’s a couple of years ago – before you moved here), there were a group of people who had wells that had gone murky or dry. They got together, and said that this had never happened before. It must be that guy that is pumping water for sale. Obviously!
So they held a meeting (Gabriola’s obvious response), at a local park, and in the evening, just as dark was coming on. But a strange thing happened! Gabriola Groundwater Management Society asked if they could study the problem, and report back in a week. (Supermen to the rescue, or kick the can down the road, it depends on your point of view.)
It turned out that the solution was well watchers (what’s that?) placed in wells surrounding the area of the pumping. (Well watchers measure the water level in a well, up or down.) So if the pumping stopped for a weekend, the wells that went back up were in the zone! (It’s called the zone of influence, but it means that pumping affects the well.)
An agreement was reached to stop pumping when a well watcher on the pumped well showed the water table (the level of the water in the earth) close to a danger level for an adjacent well. Problem solved, and no lynch mob. (And then the winter rains came and we all forgot about the problem.)
Sound confusing? Think of a big pile of sand covering all of Gabriola, say 200 feet deep. In the winter the rains come and fill the sand with water. Most of it seeps off the edges into the sea. Some is used by trees, some by you taking your supply. Off in one corner imagine there are wells and pumping for sale. This only impacts a small corner, but does reduce the water running into the sea, sort of grabbing before it can seep away, but moving it from here to there. For the corner there is an impact that we measure with well watchers. For the rest of Gabriola water runs downhill, from high areas to lower areas, eventually running over the edges until the winter rains come.
If the corner had a 200 foot vertical pipe to contain the rain, and if the pumping came out of the pipe, then the pumping would reduce the water table in the pipe. But that’s not what the Gabriola underground looks like. We have a layer cake of shale and sandstone, all of it fractured, with water going downhill. Sort of like your pile of sand.
Having mentioned wells going dry, some new residents will worry all winter. If you really want to find out what is going on, a brilliant local man invented a method of measuring the depth of water in the well, called a well watcher.
This simple device works by pumping air down a thin tube to the bottom of the well. The tube is open at the end, allowing the air to bubble out. The pressure of the air required to have it bubble is then the same as the pressure of the water at the end of the tube, which can then be converted into the height of the water in the well. The dial on the well watcher is calibrated in feet of water. Gabriola Groundwater Management Society (GGMS) members can have well watchers installed at cost.
Salt Water intrusion for people living with wells going below sea level can be solved by running the well watcher with an air compressor, and an electrical pressure switch that turns off the well pump when the water reaches a critical level.
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