Vainwater Catchment?

First, I want to make it abundanenly clear I fully support the use of rainwater catchment to act as a supplement to one’s regular household supply for gardening. In a pinch it can be used for low summer well yields, and, properly designed it can be used as a marginal water supply system.

However, it is important to note its limitations and appropriate/cost effective applications.

In that regard, lets first take a look at the practical math of rainwater catchment on Salt Spring Island.

1. To obtain a CRD building permit for a house, using rainwater catchment as your source of potable water, it is my understanding you require 1500 square feet of catchment area – about the size of a roof on a 1400 sf, single level, home.

2. It rains about 3 feet each year on Salt Spring, which means you would be able to catch, at an absolute maximum 3’ x 1500’ – 4500 cubic feet of rain. Each cubic foot holds 6.22 Imperial gallons = 27,990 gallons per year.

3. Maximum daily available water supply is equal to 76.68 gallons.

4. Equivalent gallons per minute to a well’s output requires we first convert 76.68 Imperial gallons to US gallons, (since well outputs are rated in US gallons) = 92.08 US gallons.  (27,990/365)

5. 92.08 US gallons per day = .06 gallons per minute. (92.08/24hours = 3.83gph   3.83gph/60 = 0.063 gpm.)

6. Thus the maximum water output you can achieve solely through rainwater catchment is 63/1000ths of a gallon per minute. In other words, the output of a 1 gpm well is the equivalent to the absolute maximum yield 15.87 rainwater catchment systems as described above.

7. This means, if you accept/support rainwater catchment as a potential solution to water supply on the island, then any well, sustainably producing 1 gpm, can equally support 15 homes.

When we apply this math to our existing land use bylaws we find ourselves running smack dab into hypocrisies, absurdities, and unnecessities.

Let’s look at absurdity first.

Rainwater catchment is mandatory for use with 600sf to 900sf cottages, used for permanent rentals. This requirement was established when Bylaw 512 was crafted and signed into law two years ago by Trustees Grove and Patrick. The Bylaw “legalized” 411 of the 1300 potential properties (which can legally have a cottage) for long term rentals.

When I say “mandatory,” it means even if you have a 20 gallon a minute well on your property, you STILL have to install an engineered, approximately $20,000, rainwater catchment system.

However, apparently neither the Trustees or Islands Trust Staff did the above rainwater math when they were preparing, and discussing, the permanent rental cottage idea for a couple of years.

Remember the maximum amount of rainwater a 1500sf house can capture? Well, lets do the math for a 600 sf cottage. 600/1500 x 76.68 gallons per day = 30.67 gallons per day = 0.02 gallons per minute equivalent.

Now consider that in order to legally construct a seasonal cottage (which is an accessory use on a property) you need to first build a principal residence which requires proof of potable water by the CRD. Typically, if you are on a well, as the majority of 3 acre, island properties which qualify for having a cottage are, your output is going to be sufficient to supply your house AND an additional 0.02 US gallons per minute (which is  2.66 Imperial OUNCES a minute).

For a practical demonstration of the absurdity of it all, take out your one cup (8 ounce) measure from your cupboard, go to your kitchen tap, turn it on to a tiny dribble and time how long it takes to get to fill up to the 3 ounce line. I guarantee it won’t be 60 seconds.

That dribble = a mandatory $20,000+ cost to the property owner that is being “encouraged” to provide a long term, affordable, rental unit. A two bedroom, 900sf cottage’s mandatory, “dribble equivalent” is just 4 Imperial ounces per minute.

Okay, now let’s move on to hypocrisies.

Given Trust Staff and the two Trustees came up with, and approved, Bylaw 512, it would be reasonable to assume they believe a family of four, living in a 2 bedroom, 900 sf, cottage, can survive on one ounce per minute each = 9 gallons per day each (total of 36 gallons per day). Then answer me this – why on Earth would they turn around and require the following for secondary suites?

3.16.8 Where a lot is supplied by groundwater, a building containing a secondary suite must have sufficient available groundwater

First, a secondary suite is limited to 90 square metres = 968 sf.  I’m going out on a limb here and suggest that what’s good for the cottage goose is good for the secondary suite gander.

Section 3.16.8 is followed by this informational note.
Information Note: At time of Building Permit application, the Capital Regional District requires specific amounts of potable water be demonstrated, and proof of adequate septic capacity be provided, prior to issuing approvals.

And there we have another absurdity. It doesn’t matter what the bylaw wants…when it comes time to build a secondary suite the CRD Building Inspection Department is going to require “specific amounts of potable water.” So why the hell do we need another government’s involvement/approval if, at the end of the day, the CRD is going to ensure there is “adequate” water….something arguably in the range of 4 ounces a minute according to Staff and our existing Trustees.

The same is true when it comes to subdivision requirements.

To subdivide a property, an application must be made to the Ministry of Transportation and Infrastructure (MOTI). MOTI requires proof of potable water (usually a drilled well).

As noted above, CRD Building Inspection requires proof of potable water at time of building.

Two levels of government ensuring there is adequate water.

Why then do we need a “pig in the middle,” 3rd level of government, to ensure there is adequate water? Why can’t we trust MOTI and CRD to do their jobs? I challenge anyone to show me just ONE example of a property owner being able to escape MOTI’s or CRD’s proof of potable water.

The additional cost in time, energy and money to an applicant, in complying with the local Islands Trust regulations can be in the tens of thousands of dollars and months of time.

During my term as your representative, I attempted, without success, to have Trust Council remove the Trust from the water approval business due to the liability associated with water approvals. I also attempted to remove from our local bylaws reference to proof of water, thereby hoping to reduce staff time, and taxpayer dollars, on a wasted, redundant mission.

In a day and age of hyperinflation, rising construction costs, and a housing crisis on steroids, it is time to get rid of the “pig in the middle,” 3rd level of government water approval, and the waste of valuable staff time.

The water quantity approval issue is well covered. Let’s save some of our hard earned tax dollars.

Lastly, in spite of it being common knowledge, there doesn’t appear to be any rationality associated with making blanket regulations for the whole island when it comes to water.

Salt Spring is naturally split into 3 primary geological formations. The northern 1/3 of the island is primarily sandstone, the middle and southern thirds are primarily fractured granite.

Sandstone starts out as level layers of sand on the ocean bottom. Millions of years pass and that sand is solidified into stone. Tectonic action can buckle the level layers upward, resulting in a sandstone ridge – like Channel Ridge.

If the sandstone buckles high enough it will fracture, creating a natural aquifer where rainfall runs into the fractures and can create huge fresh water aquifers/reservoirs.

However, if it doesn’t buckle high enough, the sandstone does not fracture, and thus becomes an impenetrable barrier to rain. Suneagle area is a good example of this, as is a good portion of the northern 1/3 of the island. You can drill down 500’ and not hit a fracture.

It is in those areas of poor fracturing that water problems occur. Virtually everywhere you can drill a well and hit a good supply of water.

Thus, while the idealism expressed as rainwater catchment can work, the questions are (a) is it really necessary in every case, (b) is it cost effective, and (c) does it even make sense in most cases? IMO, the answer to all three questions is “No.”

Prove me wrong with a rational argument. I’m all ears.

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