Environmental Sensitivity Data for High Spill Risk Areas

Environmental Sensitivity Data for High Spill Risk Areas

New product

Responders’ Need for Accurate ESI Maps: Are We Prepared for Oil Spills at Niagara Falls and Mackinac Island?: So what would happen if there was an oil spill at Niagara Falls or Mackinac Island? This possibility is why NOAA develops Environmental Sensitivity Index (ESI) maps to prepare for potential oil spill disasters.

This project will update the Environmental Sensitivity Index maps for the Straits of Mackinac, and the St. Clair-Detroit River System. Environmental Sensitivity Index (ESI) maps are a NOAA product that provides a concise summary of coastal resources that are at risk if an oil or chemical spill occurs nearby. Examples of at-risk resources include biological resources (such as shorebirds and mussel beds), sensitive shorelines (such as marshes and coastal wetlands), and human-use resources (such as public beaches and parks).

When an oil spill occurs, ESI maps help responders meet one of the main response objectives: reducing the environmental consequences of the spill and the cleanup efforts. Additionally, planners use ESI maps before a spill happens (such as during a drill and for mandated area contingency plans) to identify vulnerable locations, establish protection priorities, and identify cleanup strategies. State and federal agencies throughout the Great Lakes use ESI maps for both response planning and real-time response decisions.

The Straits of Mackinac and St. Clair-Detroit River System are especially ecologically complex and diverse areas in the Great Lakes. The Straits of Mackinac has a number of state-managed natural areas and preserves that include sensitive habitat types. A substantial amount of restoration has occurred in the St. Clair-Detroit River System since the ESI maps were produced in the early 1980s. Enbridge Line 5, which has received a substantial amount of public and political attention due to its age, crosses both the Straits of Mackinac and the St. Clair River. Additionally both areas are high traffic shipping routes, with refineries located along the St. Clair-Detroit River corridor. An updated ESI product will improve planning by response agencies and decision-makers during an incident, providing necessary protection to sensitive and rare habitats in the Great Lakes as well as restoration investment.

GLRI Funding
FY2024: $500,000

FY2023: $2,250,000

FY2022: $2,300,000

FY2021: $50,000


Other partners:
State, federal, local and industrial agencies along with other experts and stakeholder groups