Shoreline landowners face challenges to manage erosion, wildlife habitat, slope stability and drainage. Many shoreline properties have a steep slope bordering the water called a bluff. Without proper management, these slopes can become unstable and lead to erosion or landslides. Development can harm these shorelines, but landowners can take simple steps to mitigate their impact and improve shoreline structure. Click here for an excellent presentation on shoreline management from the Northwest Straits Foundation, or keep reading for more information.
A major challenge shoreline landowners face is slope stability. An unstable slope can lead to landslides that damage property and habitat. The main factors affecting slope stability are soil type, drainage and vegetation. Click here for information on slope stabilization techniques.
Warning signs of potential instability:
- Slumping soil surface at the top
- Overhanging vegetation/dangling roots
- Cracks in the soil and spongy depressions
- Terracing, rills and gullies on face
- Water-loving herbaceous plants on face
- Leaning trees on face
- Soil piles at base
- English Ivy
Development Affects Shorelines
Development can have a big impact on shorelines by changing vegetation, geology and drainage in the area.
- Trees and shrubs soak up rainwater, so clearing them increases runoff
- Cutting down or topping trees weakens slopes and increases the risk of slides
- Soil compaction and impervious surfaces increase runoff and erosion
What Should Landowners Do?
Here are the top 5 things that shoreline landowners can do to help retain a slope:
- Keep or plant trees and shrubs on and above a slope
- Use good pruning techniques to create view windows, don't use tree topping
- Connect downspouts to solid-wall pipes that discharge at the bottom of a slope, and clean gutters annually
- Compost yard waste; don't throw yard waste on slopes
- Move heavy objects and materials away from the edge of a slope