The population count of Washington County, MD was 148,913 in 2014.


Population Change

Above charts are based on data from the U.S. Census American Community Survey | ODN Dataset | API - Notes:

1. ODN datasets and APIs are subject to change and may differ in format from the original source data in order to provide a user-friendly experience on this site.

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Demographics and Population Datasets Involving Washington County, MD

  • API

    Choose Maryland: Compare Counties - Demographics | Last Updated 2016-11-23T16:03:53.000Z

    Population profile - total, rate of change, age, and density.

  • API

    Minority Business Enterprise: Statewide Directory - MBE, DBE (Disadvantaged Business Enterprise), SBE (Small Business Enterprise), and ACDBE (Airport Concession Disadvantaged Enterprise) Certified Businesses | Last Updated 2016-11-23T16:01:55.000Z

    MBE, DBE (Disadvantaged Business Enterprise), SBE (Small Business Enterprise) and ACDBE (Airport Concession Disadvantaged Enterprise) certified businesses are all shown. This dataset contains a list of businesses certified by Minority Business Enterprise (MBE) within the state of Maryland. This program is affiliated with the Maryland Department of Transportation (MDOT) Data are continually updated at MDOT's website for MBE: This dataset was created on Jan. 14 2016 and therefore shows all businesses certified as of that date. The Department of Information Technology (DoIT) will update this dataset using MDOT's source data, at least once per month moving forward. If you have questions about the dataset or data please contact

  • API

    Maryland Resident Population Per Square Mile: 2010-2012 | Last Updated 2016-11-30T15:59:29.000Z

    Resident population density for Maryland and Jurisdictions per square mile from 2010 to 2012. Source: U.S. Bureau of Census

  • API

    WAOFM - Census - Population and Housing, 2000 and 2010 | Last Updated 2016-08-09T16:23:33.000Z

    Population and housing information extracted from decennial census Public Law 94-171 redistricting summary files for Washington state for years 2000 and 2010.

  • API

    Surface Water Quality Assessments | Last Updated 2016-11-23T16:35:05.000Z

    This is the 2014 Integrated Report. EPA approved this submission in accordance with Sections 303(d), 305(b), and 314(l) of the Clean Water Act, on October 16, 2015. The Integrated Report (IR) combines two water quality reports required under sections 305(b) and 303(d) of the federal Clean Water Act. Section 305(b) requires states, territories and authorized tribes to perform annual water quality assessments to determine the status of jurisdictional waters. Section 303(d) requires states, territories and authorized tribes to identify waters assessed as not meeting water quality standards(see Code of Maryland Regulations 26.08.02). Waters that do not meet standards may require a Total Maximum Daily Load to determine the maximum amount of an impairing substance or pollutant that a particular water body can assimilate and still meet water quality criteria. Historically, the 303(d) List and the 305(b) report were submitted to the Environmental Protection Agency (EPA) as separate documents but more recent guidance has called for combining these two reports into a single biennial publication. More information is available at A searchable version of this data is available at

  • API

    Water Point Source Sample Results | Last Updated 2016-11-30T14:53:17.000Z

    Discharge monitoring reports (DMRs) and monthly operating reports (MORs) for the 58 major WWTPs, 215 minor WWTPs, and 10 major industrial point sources within the State of Maryland and are stored in MDE’s point source database. This data set contains results for nutrients such as phosphorous and nitrogen that may impact water quality in the Chesapeake Bay. This dataset covers the time period from 2008 to 2013.

  • API

    Crude by Rail - City Mileage (Data table) | Last Updated 2015-07-06T22:18:33.000Z

    Dataset created by clipping selected rail lines (RROWNER1 = PSAP or BNSF or TRMW or UP or PNWR or TMBL) from the US DOT "rail_lines" shapefile to the WA DOT "city limits at 24k shapefile, then joining the resulting polyline file to the "city limits at 24k" file and summing the numeric attributes.

  • API

    Maryland Total Change in Resident Population: 2000-2013 | Last Updated 2016-11-30T14:37:56.000Z

    Total Change in Resident Population in Maryland and its Jurisdictions by year from 2000 to 2013

  • API

    G2: 2014 Results WA Certified Firms | Last Updated 2015-03-17T21:51:33.000Z

    Report of all certified firms to date (May 28, 2014) including State and Federal certifications. Please note: The certification status of firms reported in our database can change daily. Please contact OMWBE directly for more information or to seek confirmation of a business's certification status.

  • API

    Detention Center Inmate Population Statistics: 2009 - 2014 | Last Updated 2015-04-29T18:08:53.000Z

    Statistical information regarding inmate population by year and month. Included average daily inmate population, number of meals served, number of admissions, number of releases, immigration detainee average population and U.S. Marshall detainee