9 FEMA areas

Riverine Flooding Risk by City in Pennsylvania

Compare 9 cities using FEMA's relative riverine flooding scores and annualized frequency for the county-equivalent areas shown.

Highest relative score

98.7/100

Dauphin County

Covered cities: Harrisburg

Lowest relative score in this set

72.2/100

York County

Covered cities: York

These are relative FEMA scores for county-equivalent areas. They are not annual probabilities or property-level findings.

Pennsylvania riverine flooding rankings

Cities sharing a FEMA area are grouped together and receive the same score.

RankFEMA area and citiesRatingScoreAnnualized frequency
#1

Dauphin County

Harrisburg
Relatively High98.7/1002.208 per year
#2

Lackawanna County

Scranton
Relatively High96.6/1001.583 per year
#3

Philadelphia County

Philadelphia
Relatively High94.9/1005.917 per year
#4

Berks County

Reading
Relatively Moderate90.7/1005.208 per year
#5

Lancaster County

Lancaster
Relatively Moderate88.1/1003.750 per year
#6

Allegheny County

Pittsburgh
Relatively Moderate84.1/1007.625 per year
#7

Erie County

Erie
Relatively Moderate83.9/1002.167 per year
#8

Lehigh County

Allentown
Relatively Moderate81.4/1003.375 per year
#9

York County

York
Relatively Low72.2/1003.917 per year

Occurrence thresholds vary by hazard. The FEMA methodology defines the value for each hazard.

Preparing for riverine flooding

Ready.gov Be Informed ↗

For a home or move

  • ✓Confirm the exact hazard using official local maps before making property or insurance decisions.
  • ✓Review policy exclusions, deductibles, and temporary-living coverage with a licensed professional.
  • ✓Keep inspections, inventories, and critical documents in a secure location you can access after an emergency.

For a household plan

  • ✓Know how local officials issue warnings and evacuation instructions.
  • ✓Maintain water, food, lighting, medications, and communications for several days.
  • ✓Create a household communication plan and practice it before an emergency.

Questions about riverine flooding risk in Pennsylvania

Which covered Pennsylvania cities have the highest relative riverine flooding risk?

Harrisburg use FEMA data for Dauphin County, which has the highest relative riverine flooding score in this covered set at 98.7/100. Cities sharing the same FEMA area share the same score.

Which covered Pennsylvania area has the lowest relative riverine flooding score?

York County has the lowest score in this covered set at 72.2/100. This is a relative FEMA comparison, not a declaration that every property there is safe.

Are these riverine flooding figures city-level?

No. The city links provide geographic navigation, while the scores and frequencies cover the FEMA county-equivalent areas shown in the table. Address-level conditions require local maps and property details.

Is the FEMA relative score an annual probability?

No. The relative score compares FEMA areas on a 0–100 scale. Annualized frequency appears separately with hazard-specific units.

Source: FEMA National Risk Index v1.19.0, released March 2023. Hazard data covers FEMA county-equivalent areas.

FEMA source ↗Our methodology →