The population count of New Castle County, DE was 555,133 in 2018. The population count of Mercer County, NJ was 368,762 in 2018. The population count of Delaware County, PA was 563,527 in 2018.
Population
Population Change
Above charts are based on data from the U.S. Census American Community Survey | ODN Dataset | API -
Demographics and Population Datasets Involving Delaware County, PA or Mercer County, NJ or New Castle County, DE
- API
Current Descriptive Data of Municipal Wastewater Treatment Plants
data.ny.gov | Last Updated 2019-06-10T18:04:47.000ZData containing municipal wastewater treatment plant design other features, with data current through the most recent survey.