U of C Professor Champions Elbow River Protection
by C. Lacombe
The many people that drink Elbow River water may be making important decisions by default and Professor Dr. Cathryn Ryan would prefer to see that change to informed decision making.
Ryan and her students have studied the Elbow River, its water and its watershed for years. Students tested well water at Bragg Creek kitchen taps, checked Elbow River invertebrates, tested river water quality and studied hydro geology upstream of the Glenmore Reservoir.
According to Ryan, Al Sosiak, a recently retired limnolgist Alberta Environment, said for many years that the Elbow is the only river in the world that he's aware of whose major end use is drinking water.
The Elbow River is small, less than one tenth the size of the Bow River, but supplies 40 – 45% of Calgary's drinking water. Sosiak first showed water quality degradation in the Elbow River close to Calgary in 1999. Sosiak and Dixon (from The City of Calgary) checked water quality again in 2005 and Ryan studied it with her students in 2016 to find that the degradation continues – mainly in the reaches closest to the Glenmore reservoir.
Ryan says she believes that water quality degradation is related to development on the river-connected alluvial aquifer, a thin ribbon of land next to the river and not even continuous on both sides. She points out that a good portion of the Elbow River headwaters are in Kananaskis Country. The eastern slopes experience some stress from forestry and recreation, but it is the land in and just west of Calgary where urban development has a significant effect.
The Elbow River is about 120 kilometres long, but most of the degradation takes place in the 60 kilometres between Bragg Creek and the Glenmore Reservoir, where a major treatment plant cleans water for Calgarians and others to drink.
“Everyone wants to live near water and that means on the river-connected alluvial aquifer; which is the worst place in terms of protecting the watershed,” Ryan says. “If Calgary put the money together to buy and protect the river-connected alluvial aquifer land, future generations would be forever grateful.”
When it comes to drinking water, you can protect the source water and treat it less or you can build ever more complex water treatment plants as the source water degrades. Ryan points out that Calgarians are making a choice by default without having any discussion around it.
She says that there are 21 square kilometres of undeveloped alluvial aquifer in Rocky View County that could protect Elbow River water quality for a long time if that land was under protection. She explains that this piece of land is mostly sand and gravel; which means that river water flows in and out of it often. Anything happening on the land in that area is happening in the river. This situation also occurs in Calgary along the river, but the city happened before much of the hydrological science of today. Ryan says that the remaining 21-square-kilometre parcel sits mainly undeveloped right now, but developers own half of it.”
Also, Bragg Creek has a licence to flow treated wastewater into the Elbow and there may be four more effluent licences approved in the coming years. “Do we really want to license effluent into this small river whose major end use is drinking water? The interface between science and policy is hugely challenging,” she says. “Especially given most of the watershed is not in the City of Calgary, who can mostly benefit from its protection.”
There are probably 12 different policies that pertain to water supply, land use and water quality management. These range through federal, provincial and municipal laws, regulations and guidelines. Ryan would like to see a more holistic approach to managing watershed health and more people engaged in the conversation because an informed citizenry might lead to different policy. Right now, very few people take an active role in making these decisions and hundreds of thousands of people drink the water.
“I wish there was a way to engage Albertans more meaningfully in these decisions that have implications for future generations,” she adds.
Dr C. Ryan Professor Geoscience & BSc Environmental Science Program
Understanding the Old Water Paradigm
Ryan explained that in her continued studies she would like to explore and gain a better understanding of the Old Water Paradigm.
Rain falls from the sky and hits the ground all over the watershed. River flow increases very soon after and in proportion to the amount of rainfall.
Using water isotopes, researchers can fingerprint the water in the rainfall and in the change in river water isotopes. They can see that the water going into the river isn't the current rainfall, but older water. Old Water may be a couple of months or years old and should not be confused with fossil water that is thousands of years old and trapped deep in geologic formations.
The speculation is that rainfall enters the alluvial aquifer and pushes water from it into the river.
Ground water that flows into a river is called base flow. It flows even when the mountains are frozen and Alberta is in the grip of winter. Ryan would like a better understanding of when and how much water flows from the Rockies and the alluvial aquifer in terms of seasonal flows and individual storm events.
Ryan insists, “It's important to understand how the river flows will change with climate change and how to manage this small river into the future.”