Rewilding Our Rivers: The Riparian Edge by Lauren Eden
So far in the Rewilding our Rivers Discussion Series, we have discovered the importance of healthy soil systems and wetlands in the attenuation of water during flooding events. The previous two blogs talked about how soils rich in organic matter hold and retain more water, and how wetlands function like sponges across the landscape absorbing surface water runoff subsequently replenishing aquifers. In addition to ensuring that Alberta’s soils and wetlands are healthy, riparian zones also play a beneficial role in flood mitigation.
The riparian edge is where aquatic and terrestrial ecologies interface; formed by the merging of land and a river, lake, or stream. As unique ecosystems, riparian zones provide a vast array of ecological goods and services including decreased soil erosion; storing and recycling of organic matter; providing habitat for fish and wildlife; and improving water quality through the removal of nutrients such as nitrogen and phosphorus from surface and subsurface water. The functioning of these many goods and services is highly dependent on the width of riparian vegetation; at minimum a riparian zone should extend over the stream bank and 5 to 10 metres onto the floodplain[1].
Rewilding Our Rivers: Wetlands – Nature’s Kidneys by Lauren Eden
Last week we learned the value of healthy soils and their role in flood mitigation . This week in honour of World Wetland Day 2014 on February 2, the Rewilding Our Rivers Discussion Series will turn its attention to the significance of wetlands and their potential role in flood mitigation.
Wetlands are often called planet earth’s kidneys because of their ability to purify our water supply through natural filtration systems that absorb heavy metals and other harmful containments (like phosphorus). Wetlands are complex ecologies that offer many benefits and functions to our shared bio systems – most notably, they are able to retain and store water. In essence, wetlands act like sponges; they absorb rainfall, slowly saturate soil systems, and eventually recharge aquifers. By retaining and storing water, wetlands reduce the speed and volume of water entering our streams and rivers. This can be particularly important for some flood events.
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| “Wetlands near Utikuma Lake, northern Alberta 2010” by Gord McKenna is licenced under CC BY 2.0. |
The Ramsar Convention defines wetlands as areas of marshes, bogs, fens and peatlands. They are ecosystems that contain plant and animal life in water saturated areas. A wetlands’ ability to retain and store water is greatly dependent on its soil system. For instance, peatlands have a significantly greater capacity to retain and store water because they are made up of rich organic matter developed over thousands of years. This highlights the symbiotic relationship between wetlands and healthy soil systems and the role they can play in flood mitigation. Peatlands have become important ecosystems to protect on a global scale due to the simple fact that they are nearly impossible to reconstruct. One example of this is located in our back yard. Alberta is home to a UNESCO World Heritage Site and a Ramsar Convention Wetland of international importance located in the Peace-Athabasca Delta in the Wood Buffalo National Park.
What is Old is New Again: Elbow River Historical Detention and Diversion Sites Report
A new report on historically identified detention and diversion sites, commissioned by the Alberta Flood Recovery Task Force and executed by Alberta WaterSMART, has been added to the Flood Recovery Task Force page.
This report explores 100-110 years of historical documentation on previously considered options for both drought and flood mitigation in the Elbow River Watershed. Many of the potential options come from reports by the Department of the Interior (established in 1873 by Sir John A. MacDonald) which had surveyed the land by foot looking for sites where the topography of Alberta could be used to create reservoirs to combat drought.
Executive Summary
The purpose of this study is to review historical records to identify previously proposed detention and diversion sites on the Elbow River, and determine if these historical sites have any merit for further investigation and consideration by the Government of Alberta (GoA) as an alternative to the mitigation options currently being reviewed by the Flood Recovery Task Force.
An initial historical review of potential detention and diversion sites on the Elbow River provided twelve possible options that could be implemented to mitigate for both flood and drought.
Of the twelve identified historical detention and diversion sites it is recommended that the Priddis Creek diversion be seriously considered as an option for flood and drought mitigation. The Priddis Creek diversion is designed to mitigate for flooding upstream of Bragg Creek and the City of Calgary using the natural creek bed and low lying topographical areas for channeling the water flows. By using natural topography the Priddis Creek diversion has a greater potential to slow down the water; subsequently reducing peak flows. It is also recommended that the historical resevoir sites identifed by the Department of Interior in the 1890s, along with the McLean Site, should be further investigated for feasibility. These storage sites are recommended due to their use of natural topography and their ability to mitigate for flooding upstream of Bragg Creek and the City of Calgary.
In order to ensure that all the flood mitigation options are considered for all watersheds throughout Alberta, Alberta WaterSMART recommends further investigation into all mitigation options by continuing to undertake this type of historical analysis for all watersheds throughout Alberta.
Some of the current proposed options have received criticism by the water community for the potential impact they would have on the watershed. Do any of these proposed options seem like promising alternatives? If not, what options would you recommend exploring?
Rewilding Our Rivers: The Ecological Argument For Healthy Soils And Their Role In Flood Mitigation by Lauren Eden
Welcome back to the discussion series Rewilding Our Rivers – a look at natural flood mitigation options for Alberta. This week we turn our attention to the importance of healthy soils and how the building of organic matter can play a significant role in flood mitigation.
Soil is made up of a complex web of life, where a single teaspoon of soil can contain billions of living organisms. Created from the functions of its many parts including bacteria, fungi, minerals, air and water, nurtured by sun making soil a living network from which all plant life sprouts.
Healthy soil is considered one of the most complex ecosystems on the planet. Like all living organisms, soil requires nutrients (food), water, and air. Organic matter is essentially the soil’s food system created from decomposed organic material such as dead plants (carbon) or animal manure (nitrogen). The decomposition of this matter into the soil system creates a topsoil layer called humus; a dark black living structure. Humus is essentially mature compost that has reached a state of stability, where it needs no further decomposing. Humus, a dense organic matter, significantly increases the soil system’s ability to retain nutrients and moisture. Thus, healthy soil results in structure that is rich in organic matter enabling it to hold, filter, and purify water[1].
Rewilding Our Rivers: A Discussion Series On Natural Flood Mitigation Options by Lauren Eden
A recent article written in The Guardian by scientist George Monbiot [1]discusses emergent research coming out of the United Kingdom that tells us rivers do not necessarily store the precipitation that falls in their catchments; but rather the majority of the precipitation is stored in the soils of their floodplains This scientific finding directly questions the value of traditional flood mitigation measures, such as canalizing and dredging rivers, techniques that are now known to increase flow rates to downstream communities.
Some scientists are now pushing for the implementation of softer engineered solutions, such as the rewilding of our rivers. Rewilding rivers, among other elements, requires the redesigning of curves and snags back into the river system along with connecting rivers to uninhabited land designated for flooding. The likelihood for downstream flooding can be greatly reduced by creating a catchment for sediment and rock, ultimately reducing the energy and speed of the river.
Safeguarding the Source by Kevin Van Tighem
Naturalist, hunter and former Banff National Park superintendent Kevin Van Tighem revisits his July 2013 article entitled “Safeguarding the Source”,
This article, published in the July 2013 edition of Alberta Views magazine, remains no less relevant in the wake of last year’s destructive flooding (driven by an exceptional precipitation event but made worse by damaged headwaters landscapes that shed the water too fast) and by the public consultations, which will conclude this month, on a draft land use plan for the South Saskatchewan Regional Plan.
Our New Look
We at the Alberta WaterPortal are pleased to reveal our new website. A driving force behind the redesign of the Alberta WaterPortal was the desire to create a website with more intuitive navigation. Content is now sorted into three major categories: Learn, Work, and Enjoy.
Learn
The “Learn” area acts as a library of knowledge on water to inform users about the origins of Alberta’s water, how water is used, water management in our province, the relationship between water, energy and food, and the impact of water on daily life.
Work
The “Work” area presents projects and research conducted by the Alberta water community, showcases existing groups within the water community, and provides a toolkit of resources for those whose work/volunteering revolves around water. Visitors to the Alberta WaterPortal can learn more about the Watershed Planning and Advisory Councils (WPACs), Environmental Non-Governmental Organizations (ENGOs), industry organizations, and academic and government institutions focused on water-related issues. We will be adding to the water community section over the coming weeks and if you would like to see your organization included please contact us.
Enjoy
The “Enjoy” area focuses on personal, primarily recreational, uses of water. Download a water related app for your mobile device, learn about water conservation techniques, or check for weather advisories to ensure that Alberta’s water may be enjoyed responsibly and safely.
What else is new?
Alberta’s New Wetland Policy: Review by Jay White
The Province of Alberta has been operating under a draft wetland policy for the white zone (the lower third of the Province) for the past 20 years since draft policy was created for white zone wetlands and a discussion paper created for green zone wetlands. Many of us have been patiently waiting for a comprehensive policy that addresses all of the wetlands in Alberta, and on September 10, 2013 our wish was granted by Environment Minister Diana McQueen.
The biggest bombshell in the new comprehensive policy is the removal of the no-net loss provisions and philosophy contained within the previous draft policy. The current policy simply does not allow for an increase in wetland area in the province, nor does it address past losses. The removal is essentially an admission of our failure as a Province to even come close to meeting the objectives of no net loss. And, with losses of up to 70% of our white zone (prairie pothole) wetlands in the south, over 300,000 hectares of wetlands in the oil sands and over 90% loss of wetlands in major urban centres, it is hard to argue with trying to continue to giving lip service to the no net loss principles of avoid, minimize and compensate.
The 2013 Great Flood: Actions to Mitigate, Manage, and Control Future Floods
A final copy of The 2013 Great Alberta Flood: Actions to Mitigate, Manage and Control Future Floods whitepaper has been released. This document consists of collaborative recommendations made by Canada’s leading water experts. The document has been evolving for over a month thanks to the received feedback from water experts and Albertans. This document was written as a collaborative teamwork to determine the recommended actions that should be taken to strategize for future flooding.
During the creation of this report, two draft versions were posted here with the request for public feedback. The response was excellent, leading to the creation of a separate feedback document titled The 2013 Great Alberta Flood: Actions to Mitigate, Manage and Control Future Floods Feedback Compendium which catelogues the feedback received.
We’d like to thank everyone who sent in feedback on the draft iteration when it was posed two weeks ago. Additional information about this document will be posted on the Alberta WaterSMART website as it arises.
If you didn’t get a chance to share your feedback or if you have additional thoughts after reading the final version of the whitepaper please do not hesitate to contact us, and like always please continue to check our news section for updates on what is happening around water in Alberta.
Brad Stelfox: Living at the River’s Edge
The 2013 flood of the Bow River basin has triggered a long-overdue conversation about the natural and man-made factors that caused or contributed to these types of events. Across society, people are now asking pointed questions that relate to mitigation, prevention, headwater management, overlapping landuses, floodplain infrastructure, climate change, and flood proofing.
The WaterSMART White Paper provides an excellent broad overview of the complexity of this watershed issue and makes clear that integrated solutions are required to meaningfully address this challenge. Appropriately, the WaterSMART report identifies that both engineering and landscape management approaches are required if watershed integrity of the Bow River basin is to be conserved and risk to infrastructure is to managed at an acceptable level.
As a resident of the Sunnyside community in Calgary, our neighborhood was extensively flooded and most families experienced serious damage to their basements, and in some cases, structural damage to their homes. In comparison to the residents of lower Benchlands, High River, and many other communities, we escaped relatively unscathed. In the aftermath of these events, we are told that those who have experienced flooding are expected to go through the emotions of anger, denial, depression and acceptance. For most affected by the flood, there is a basic need to understand what happened and what factors contributed to an event that so forcefully changed our lives. Over the next several months, more information will certainly come forward to help residents better understand the weather, landscape, and landuse dynamics that shaped this massive event, but a few thoughts are respectfully offered below to help put some of these dynamics into context.