Water is a concern on Hornby Island, as on all the Gulf Islands. Our watershed is just the island itself - the only water we have to work with is that which falls on the island in winter and is stored in the bedrock, for use in summer by ourselves and our 50,000 summer visitors.
This results in islanders having a different attitude toward water, at a level below conscious thought, just as city people (which we once were) operate on a sub-conscious assumption that there is an infinite source of water and an infinite sink into which waste water may be sent. For an islander, wastage of water literally hurts. On the islands "city folk" is a perjorative term for those who waste water and crush beer cans.
Hornby Island essentially has two seasons, rain and not-rain.
The winter rains start sometime in October, and can be quite relentless. By January, all the overburden and the easily accessible fissures in the bedrock are full. There is water standing in the fields in the agricultural areas, and the ditches and seasonal streams are full. The water level in the provincial monitoring well at the top of Sandpiper Road will rise by 5 to 6 metres.
In mid-March, the rains begin to taper off. We perceive that we are still gaining inventory, more slowly perhaps, in the winter months, as water continues to move into the less accessable fissures in the bedrock.
From May to October is the inventory draw-down season. June is usually wetter than May, which provides a final top-up for the summer. The green bars on the chart are monthly passenger loadings for the Hornby Island ferry, courtesy of BC Ferries.
By mid-August, there are signs of water depletion on the periphery of the island. Some wells run dry and some suffer intrusion of salt-water, which is an indication that we are at the limit of our resource. We only survive until the rains start again because the usage drops drastically in September.
In October the rains start again, and we perceive that the first thing that happens is that a lot of untidy material that has soaked into the ground over the summer is leached out and carried with the water. We have certainly measured it in ditch water, but also fear that it is carried into the bedrock as well. Fortunately time is on our side in allowing it to deplete over the winter.
We are like a sponge sitting on the bedrock of the ocean floor. The sponge fills up with winter rainfall, and because fresh water is less dense than salt water, it displaces saltwater downward. Contrary to popular opinion, we are informed that there is no link to the water stored in the Beaufort Range on Vancouver Island. All the water we have is what we can trap and store in the uplands of the island.
Virtually all domestic water on Hornby Islands comes from individual wells. There are only three small water systems on the island, all using well water.
Water accumulates in the uplands, the highest point on the island being almost exactly 1000' above sea level. Because fresh water is less dense than salt water, the fresh water bubble extends well below sea level. In theory, there should be 42' of fresh water below sea level for every foot above.
Most of the wells are located around the periphery of the island, where the houses are. Drilled wells of 200' depth are not unusual, and one is 500'. In summer when the groundwater inventory is being drawn down, the fresh water bubble contracts and sea water can be drawn in from the side, hence the salt intrusion.
The state of domestic sewage on the island is spotty. Treatment on individual lots may be modern, obsolete, or not at all. Many of the subdivision lots were registered as summer use only, but this has not been enforced, and is now not enforceable. Older septic systems on these lots may not have taken into consideration the high water tables in winter, when aerobic treament is not possible The island is literally overloaded in summer with all the summer houses full, and additional relatives in trailers and tents on the lawn.
This is not helped by the regulatory regime, which effectively discourages upgrading of old systems or registering new systems. The one-size-fits-all standard treatment system does not fit our situation. It is only just possible to fit a house, well, driveway, septic field and the associated set-backs on a 1\2 acre lot, but only if all your neighbours cooperate. The four foot depth of undisturbed soil above the winter water table is rare here, as it is in most of the land surrounding the Gulf of Georgia.
The real problem is that every lot must have its own water supply and its own sewage disposal. One option for improvement is to provide a common service for one or the other of these items. This might be common to two or more lots, or to whole subdivisions.
As always, Hornby Island has a contingent of concerned residents working on this. Some of the concerns are