Environmentally Friendly Anchoring in the Pacific Northwest – Best Practices

This article was created for and reviewed by the Environmentally and Socially Responsible Cruising (ESRC) Working Group using Perplexity AI. The intent is to mine the broader universe of information and to present relevant information more quickly; it is, of course, an assumption that it is as accurate as a human-written article. The ESRC Working Group would appreciate your feedback and thoughts on this approach.

Best Practices

For recreational vessels in the Pacific Northwest, minimizing environmental impact while anchoring is crucial due to the region’s sensitive habitats, including eelgrass beds, shellfish areas, and rocky outcrops. Here are tailored best practices for consumer sail and motor vessels, typically 20 to 65 feet in length.

1. Choose Your Anchoring Location Carefully

• Prefer Sand or Mud, in depths over 8 meters (27ft): Anchor in sand or mud whenever possible, avoiding areas with visible eelgrass, kelp, or rocky reefs in depths exceeding 8 meters (27 ft). These habitats are especially sensitive to anchor and chain damage.[1][3][4][6]
• Consult Charts and Local Guides: Use up-to-date nautical charts and local knowledge to identify designated anchoring areas and avoid protected or sensitive zones [2] .
• Allow for Swing Room: Ensure there is enough space for your vessel to swing 360 degrees with wind or current shifts, preventing the anchor or rode from dragging into sensitive habitats or other boats [3][4] .

2. Use Mooring Buoys When Available

• Opt for Buoys: In many Pacific Northwest anchorages, mooring buoys are provided to protect the seabed. Use these whenever possible, as they eliminate direct anchor contact with the bottom.

3. Select the Right Anchor and Gear

• Anchor Type: Use an anchor suited to the local bottom type (e.g., plough or fluke anchors for sand/mud and of a weight proportionate to the size of the boat; avoid using anchors in rocky or vegetated areas) [2][5] .
• Rode Composition: A combination of chain and rope is common. Use a length of chain at the anchor to help it set and reduce dragging, but avoid excessive chain that can sweep the bottom [2][4] .
• Scope: Use a minimum 3:1 scope if using all chain, 5:1 scope if using a combination of chain and rope and minimum of 7:1 scope if using rope (rode length to water depth plus freeboard) for secure holding, but avoid excessive rode that increases the swinging circle and potential for environmental damage. All of this is dependent on the depth and bottom type, as well as anticipated weather [4] .

4. Anchoring Technique

• Approach Slowly: Head into the wind or current, stop the boat, and lower (never throw) the anchor to the bottom [2][3] .
• Set the Anchor Gently: Let out rode gradually, backing down slowly to set the anchor without dragging it across the bottom. This minimizes disturbance to the substrate [3][4] .
• Test the Set: Once the anchor is down, gently reverse at low RPM to ensure it is holding. If it drags, reset rather than dragging it to a new location [4] .

5. Minimize Chain Sweep

• Limit Rode Length: Use only as much rode as needed for the conditions. Excessive rode increases the area impacted by the chain sweeping the bottom as the boat swings [4] .
• Consider Stern Ties: In narrow or crowded anchorages, especially common in the Pacific Northwest, use a stern tie to shore. This limits swinging and keeps the anchor and rode in a defined area, reducing environmental impact and risk of grounding [7] [8] .

6. Special Techniques for Small Boats

• Tsimshian Anchoring: For small craft or shore landings, consider techniques like the Tsimshian method, which allows you to anchor offshore and retrieve the boat with a line, minimizing time spent with the anchor on sensitive ground [5] .

7. General Environmental Precautions

• Avoid Dragging: Never drag the anchor to reposition. Always retrieve and reset.
• Inspect Before Anchoring: Visually check for sensitive habitats if water clarity allows.
• Respect Local Regulations: Some areas may prohibit anchoring or require specific practices to protect the environment.

References

1. Protecting Eelgrass When Boating
2. Anchoring & Mooring
3. Stress Free Anchoring
4. 8 Tips for Safely Anchoring Your Boat
5. Tsimshian anchoring
6. Anchor out of Eelgrass
7. Stern Tying: With a Messenger
8. Stern Ties

Eelgrass Illustration was created by Larry Eifert and is used with his generous permission.