Nelson’s main reservoir on Mountain Station Road collects water from Five Mile Creek.

Nelson’s main reservoir on Mountain Station Road collects water from Five Mile Creek.

Water: does Nelson have enough?

How does the city balance reduced flows with increased use?

With water use 30 per cent higher than average in June, the city has also been faced with low flows into its reservoirs, according to the city’s head of pubic works Colin Innes.

“That was not a huge surprise, but we saw that if that trend continued, if it was still 30 per cent more later in the summer, we could run into trouble. We need water in the reservoirs if there is a large structure fire.”

So the city imposed  Level 3 water restrictions.

“It appears people have taken the restriction to heart and we have seen a decrease in water use,” Innes says, but he emphasizes the problem doesn’t end there.

A fine line

Innes says the average amount of water entering the city’s reservoir system is 73.5 megalitres per day. (A megalitre is one million litres.) But during July only about 13.6 megalitres was arriving at the reservoirs every day — less than a fifth of the average.

At the same time, we are using more than usual because of the hot, dry weather. Average use is four megalitres per day in the winter and up to 10 in the summer. In July, Innes says, we used 11.2 megalitres per day.

So: 13.6 megalitres in, 11.2 megalitres out. We are cutting it fine, especially if we need water to fight a house fire. Or worse yet, if a forest fire encroaches on the edges of the city

Nelson’s main water source is Five Mile Creek, located in West Arm Provincial Park, which feeds into the main reservoir on Mountain Station Rd. The city also gets water from Anderson Creek in Fairview and Selous Creek at Ymir Rd. At each of those places is a diversion dam, screen assembly and electro-mechanical valves. The reservoirs feed into a distribution system that fans out across the city in 87 km of underground pipes.

Unlike many municipal water systems, Nelson’s system relies on gravity and requires no pumping. In fact the pressure has to be reduced at a number of stations around the city.

The water is disinfected with chlorine to deal with giardia and other pathogens. Many municipal water systems are filtered, but the quality of Nelson’s water makes that unnecessary.

Snowpack is crucial

Whether we have enough water depends on the snowpack: the amount of snow in the mountains and how early and quickly it melts.

“This year has been  unique across the province,” says David Campbell of the BC government’s river forecast centre,  “with warm temperatures in the winter and spring, less snow accumulated, and because of the warmth it melted off quicker than normal, so by June we had essentially no snow.”

He says that in the West Kootenay the snow level was 67 per cent of normal measured on May 1 over 30 years, and by June it had plummeted to 30 per cent.

“What we saw this year is not common. We have seen a combination of temperatures two degrees above normal for many months now, and very dry conditions through the spring and summer period. There have been other dry years, but none like this one. We are starting to see this in the rivers around the region with flows hitting historic lows for this time of year.”

Campbell says that since 1970, the snowpack in the southeastern part of the province has declined five to 10 per cent when measured on April 1, and seven to 18 per cent on May 1. He said the biggest drop happened in the decade from 2000 to 2010.

He said the declining snowpack affects the timing of when water cycles through rivers. If precipitation is rain rather than snow there is more flow through the winter than normal. For systems with no reservoir or lakes, this means there is less water around in the summer because it has already gone down, and this results in stress on ecological systems at that time.

As for climate change, Campbell said we cannot necessarily attribute changes in any given year to climate change, but “it is analogous to what is expected to be more common in the future.”

If droughts do become more common, how will the City of Nelson prepare for it?

New sources and conservation

Innes said the city would need to find new sources of water and increase water conservation. He said the city has two other water sources in mind but has not followed up on them.

“Qua Creek (south of Selous Creek) is a possibility and there is also a possibility at Grohman, but there the challenge is we would have to get it under the lake.”

Asked about the huge reservoir of water in Kootenay Lake, Innes said to turn it into drinking water would require the large investment of a filtration plant and a pumping system.

He said the Lakeside soccer fields are watered with lake water and some flushing of construction sites in Nelson is done with lake water in tanker trucks.

Water metering?

The presence of the lake poses a psychological problem for Nelson, says local environmental consultant Michael Jessen.

“We live beside this river and lake that gives us the illusion that we have a lot of water,” he says.

Jessen said we should each be paying for the water we use.

“We in Nelson have no idea of what the value of that water is, and when we don’t understand the value of it, that makes it more difficult to convince people they need to cut back, because they have little experience doing that. I think the prudent thing to do in every city is put a price on it.

“Water is an essential. We need electricity and we don’t get that for free. We need gasoline and we don’t get that free.”

Innes says there was water metering in the past two places he’s worked — Edmonton and Prince Albert — and in his experience it can help conserve water, but  metering isn’t common in BC. Metering has been adopted in recent years in Grand Forks, Rossland, and Castlegar, but not always without controversy.

Nelson has water meters at a few places in the distribution system to measure the amount used in different zones in the city, and there are meters in a few commercial buildings in town, just to gauge water use and demand. Both these systems are used for research about water use, not for billing.

Consultant recommends metering

A consultant’s report strongly recommended water metering for the city. In 2012, AquaVic Water Solutions presented its report, commissioned by council and paid for with a Columbia Basin Trust grant.

The consultants predicted a 10 to 30 per cent reduction in water use with metering, and a 20 per cent reduction in residential demand. It proposed an initial step might be to meter only businesses, institutions, and industry.

The consultants estimated setting up a metering program would initially cost about $2 million.

At that 2012 council meeting, then-mayor John Dooley and councillor Bob Adams spoke vociferously against metering on the grounds that it would not save the city any money because Nelson’s water costs are fixed (pipes in the ground) with no pumping costs.

Then-councillor Paula Kiss argued it wasn’t a matter of saving money but of saving water, and that Nelson’s fixed cost for water discriminates against people who consciously save water.

Other options?

Mayor Deb Kozak told the Star this week she isn’t against water metering but isn’t sure it’s the answer.

“Is it about grey water recycling? Or capturing storm water? Or separation of storm and sewer? Where will the most benefit for the future be? These are all things we must consider.”

Apart from metering, Jessen suggests the city could do more things.

“All new construction should have water conserving fixtures in them,” he said. “It should be mandatory that the most advanced conserving technology at the time of construction is used. All new construction should have built-in rainwater catchment. If we had captured the rain that came down in that big storm [on June 29], we would have had lots of water in our barrels.”