AUSABLE WATER WISE: Examining the river’s restoration success

When the geomorphology of a stream is stable, as in this section of the East Branch of the AuSable River in the town of Jay, improved water quality and increased biodiversity are often observed. By bringing geomorphic stability to impaired sections of river, we attempt to increase these functions and will measure them through periodic monitoring. (Photo provided)

In this season of gratitude, I am thankful for the role that trees play in our watershed and around the planet.

From sequestering carbon to providing oxygen, their ecosystem services are innumerable. The trees along and in our rivers, streams and lakes help to hold together habitats for wildlife and fresh water. I’m thankful for the many hundreds of trees we were able to plant this year in the AuSable Rover watershed.

But as biodiversity research manager for Ausable River Association, tree planting is not the only thing I do at our river restoration sites. This winter, we are launching a new research project to understand how our stream restoration projects improve habitat for fish and aquatic insects.

In the Water Wise column from May, Gary discussed the stream functions pyramid and how we use it at Ausable River Association to assess the rivers on which many communities depend — for stormwater drainage, drinking water or for water recreation.

The pyramid is composed of five categories of stream functions. The bottom of the pyramid rests upon the foundation of geology and climate, which are the primary factors that determine the development of streams within a given region. As you move up the pyramid, each function is supported by the functional category beneath it. For example, populations of fish and other aquatic organisms (biology) cannot thrive outside of the physical and chemical parameters of water quality that make their survival and reproduction possible.

Once we recognize that higher-level functions like biology and water quality in rivers and streams depend on stable geomorphology and hydraulics (the base of the pyramid), our approach to river restoration can more effectively address the root causes of dysfunction. The framework is used to establish practical project goals with the result of improved function in mind. We also use the framework as a basis for planning our assessments of past and future stream restoration projects.

Once we understand the goals of stream restoration, we can establish metrics for measuring its success. A major concern in stream restoration is the lack of monitoring after a project is completed. These projects can be expensive to implement, and much of our time is often consumed looking for funding sources to survey, design and construct projects in the many areas of the watershed.

I believe that AsRA is well-positioned to address this concern because we are not a consulting firm that moves from place to place, restoring rivers and moving on. Instead, we live and work here and have a long-term interest in restoring healthy streams, clean water, and biodiverse habitats.

This past spring, the Ausable River Association was awarded a grant from Lake Champlain Basin Program to develop and use a monitoring protocol to assess the success of our restoration efforts both from a biological perspective and looking at the restoration structures themselves. This critical funding will allow me to examine the changes in stream function and biology over a three-year period at eight sites throughout the watershed.

The project will allow myself and other staff to follow these projects through varying stages of construction. We will assess changes over time in fish and aquatic insect populations at these sites, along with water temperature and other microhabitat features, like in-stream cover and stream substrate size.

Support from LCBP and all our donors–small and large–is vital as we continue to develop and refine our approach to restoring and supporting healthy streams in the region. Our watershed is a complex landscape that reflects the balance between communities, infrastructure, recreation, and nature.

We will continue to strive to find effective tools to maintain that balance in ways that are long-lasting and self-sustaining. The work we do to monitor and refine our projects will help us to develop better ways to protect and restore the health of streams in our watershed.

Personally, it will help me to know that the young trees I plant on these banks will help to hold the habitat together for a biodiverse ecosystem over time.

(Carrianne Pershyn is the biodiversity research manager at the Ausable River Association.)

Starting at $1.44/week.

Subscribe Today