Environmental Risk Report for Merrimack County, New Hampshire
Comprehensive environmental hazard assessment
Coordinates: 43.2976°N, 71.6806°W • FIPS: 33013
Risk Assessment for Merrimack County, New Hampshire
About Merrimack County, New Hampshire
Merrimack County is a county in NH known for its humid continental climate with cold winters and warm summers. Its coastal location provides beautiful scenery but also creates unique vulnerability to storm surge and coastal flooding.
Merrimack County's environmental risk profile includes coastal and inland flooding from nor'easters and tropical remnants, severe winter storms with heavy snow and ice accumulation, and the potential for river flooding during spring snowmelt. The region's aging infrastructure can amplify the impact of these natural hazard events.
Notable historical events affecting this area include the 1938 Great New England Hurricane (13 deaths, massive timber damage across the state). These events underscore the importance of environmental risk awareness and preparedness for residents and property owners.
Notable Historical Events in New Hampshire
Understanding Risk Factors for Merrimack County
🌀 Hurricane Risk
Merrimack County is vulnerable to Atlantic hurricanes and tropical storms, particularly during the June–November season. While direct hits from major hurricanes are less frequent than in the Gulf states, nor'easters and weakening tropical systems can cause significant flooding and wind damage. Coastal erosion from repeated storm events is an ongoing concern.
🌊 Flood Risk
Merrimack County faces significant flood risk due to its coastal location. Storm surge from hurricanes and tropical systems can push water miles inland, while heavy rainfall events strain local drainage systems. FEMA flood zone maps identify multiple high-risk areas, particularly in low-lying neighborhoods near the coastline and waterways.
❄️ Winter Storm Risk
Merrimack County experiences severe winter weather including blizzards, ice storms, and dangerously low wind chills. Heavy snowfall can collapse roofs, ice accumulation can bring down power lines, and freeze-thaw cycles damage roads and infrastructure. Winter storm preparedness is essential for residents.
💨 Air Quality
Air quality monitoring in Merrimack County draws from EPA AirNow sensors measuring particulate matter (PM2.5), ozone levels, and other pollutants that affect respiratory health. Seasonal variations and agricultural or industrial activity can influence local air quality.
🔥 Wildfire Risk
Wildfire risk evaluation considers vegetation density, climate conditions, historical fire data, and terrain characteristics in Merrimack County. Seasonal weather patterns and local land management practices influence the area's fire vulnerability.
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