When Are Mussel Surveys Required in Michigan?

Mussel consultations and surveys (including reconnaissance, semi-quantitative/quantitative assessments, and relocation efforts) may be required for projects in Michigan under specific conditions.

Primary Trigger Conditions

1. Projects with Federal or State Nexus

Surveys are required to determine the potential for affecting threatened or endangered (T/E) mussel species when projects involve federal permits, funding, or state regulatory oversight.

2. Work Impacting Bottomlands

Any work occurring below the Ordinary High-Water Mark (OHWM) may trigger mussel survey requirements.

Common Project Types Requiring Mussel Surveys

• Bridge Projects: Repair, replacement, or scour countermeasure installations
• Pipeline and Utility Crossings: Stream or river crossings for infrastructure
• Outfall Work: Installation, replacement, or repair of discharge structures
• Dredging Activities: Any sediment removal from waterways
• In-Stream Construction: Including causeways and other structures
• Dam Modifications: Dam removal projects or reservoir drawdown activities

Next Steps

If your project falls into any of these categories, contact our team early in the planning process to:

• Determine specific survey requirements
• Schedule appropriate field assessments
• Ensure regulatory compliance
• Avoid project delays

This guide provides general information. Specific requirements may vary based on project location, scope, and regulatory agency jurisdiction. Consult with environmental specialists for project-specific guidance.