The Nooksack: Three Forks, One River

If we were to say the heart of Washington’s natural character are the forested mountains, then the rivers would be the arteries. Washington’s rivers flow down from the mountains into the lowlands and find the sea, carving a path filled with rich soils and even richer history. Many cities and towns here have a river nearby influencing the way people appreciate nature in their area. Here in Northwest Washington we have the Skagit, Samish and Nooksack rivers. Though these rivers have their own geomorphologic and cultural history, the Nooksack is of special interest as it has been identified as a potential salmon sanctuary in a changing climate.

Forks of the Nooksack River

The Nooksack River contains three unique forks —North, Middle and South, before flowing together to create the Mainstem Nooksack River.

The headwaters of the North Fork is in the Nooksack Cirque with glacial melt from the East Nooksack Glacier. Maple Creek is one of the many streams and tributaries that meet up with the North Fork on its way down the mountain. This creek is special because it fans out into several channels that flow through flat land to create a fan-shaped forested wetland riddled with pools and small channels beneficial to salmon and wildlife before meandering across the historic floodplain to meet up with the Nooksack. This area along the North Fork – where Maple Creek and its wetlands meet has created a distinctive ecosystem known as Maple Creek Reach. Formerly cleared for dairy and farming, restoration efforts began 20 years ago thanks to the efforts of adjacent landowners. Since 2003, when Whatcom Land Trust acquired the initial 78 acres, it has been augmenting reforestation and wetland improvements with several partners. This area is a good example of how the Land Trust works together with landowners and other local organizations to protect a sensitive natural area to benefit watershed, people and wildlife.

The An example of success for Whatcom Land Trust and the community along this fork is where Canyon Creek and the Middle Fork meet. This area is known for flooding and the river changing course due dramatic changes in flow levels during high water events, the flat terrain, and the joining of the creek with the river. When a tributary meets its river, an alluvial fan is created. Alluvial fans’ natural deposits of gravel, sand, and other sediment are incredibly important in improving habitat for many species, especially salmon, but can be problematic for property owners. headwaters come off the eastern slopes of Mount Baker’s glaciers and has a history shaped by volcanic activity. Its forested river corridors and tributary streams offer prime habitat for salmon and other wildlife and is also inviting to people.

In 2015 a high water event caused Canyon Creek to threaten landowner properties – in one case the creek rose to the homeowner’s back porch. Whatcom Land Trust was able to work together with the Department of Fish and Wildlife, Whatcom County Public Works and property owners with funding from the Salmon Recovery Funding Board to purchase the properties, remove damaged structures, and compensate property owners. In the process, Whatcom Land Trust formed lasting positive relationships with property owners to reach a common goal of accommodating the dynamic river, the wildlife dependent on it and the community who will continue to enjoy the area for generations.

The South Fork is the only fork of the Nooksack which is not glacially fed. Its headwaters come from the snow-packed eastern slopes of the Twin Sisters. Its major tributaries include Skookum, Arlecho and Cavanaugh Creeks. The South Fork also differs from the other forks because it is older. Unlike the younger and more dynamic North and Middle forks, the South Fork moves slowly and meanders on a more predictable path.

The South Fork flows through a large old valley which was carved by a glacial river of a much larger scale. The area is also prone to landslides, even though the last major one was off the Van Zandt Dike some 13,000 years ago, shown in the image below. Many smaller landslides occur on this fork, some natural and some man made. One study done in 2016 noted “habitat is degraded due to the lack of large wood in the channel and coarse sediment filling in pools, suggesting the need for protection and restoration to achieve high quality habitat”. Working to reduce landslides in this area could be beneficial to long term salmon habitat protection and overall water quality.

As each fork has its own unique topography and history, each also has its own challenges and future outlook. The North and Middle Forks will continue to experience glacial retreat in their headwaters which will likely cause low flow periods, increased temperatures and other stresses affecting salmon and wildlife. One advantage to the North and Middle Forks in a changing climate, however, is that the glaciers and snowpack feeding them are fairly high in elevation, so they are less likely to disappear. The South Fork Nooksack’s challenges with rising temperature and turbidity, especially during crucial summer months, can be addressed by protecting cold water tributaries and headwaters, and restoring maturing riparian forests. Combined, these protections will help to improve high-quality salmon rearing and spawning habitat, improve water quality and sustain summer flows.

Whatcom Land Trust’s mission to preserve and protect lands which define Whatcom County’s natural character is exemplified in our work on all three forks of the Nooksack River. Like other land trusts working with public and private landowners to protect their community’s special places amid growth and change, Whatcom Land Trust can be a leader in shaping Washington’s legacy of sustainable forestry, agriculture and growth while promoting river health.

Together we can create a shared understanding of how upstream conditions and activities affect what happens downstream. Caring for one section of the river benefits our neighbors downstream. It is possible for the river arteries of home and our state to stay healthy and functional amid a changing landscape and climate. We can be an example to other regions how communities can come together to restore and protect an iconic natural system and create a sense of place that will last forever.

Citations: Murphy, R. D. (2016). Modeling the Effects of Forecasted Climate Change and Glacier Recession on Late Summer Streamflow in the Upper Nooksack River Basin. Available at: cedar.wwu.edu/wwuet/461/ Supporting information from Dan McShane https://washingtonlandscape.blogspot.com/

Read More News from Whatcom Land Trust