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This is a Non-Federal dataset covered by different Terms of Use than Data.gov.

Combined Sewer Outfall Sewer Shed

Metadata Updated: February 5, 2025

DC Water operates a wastewater collection system comprised of "separate" and "combined" sewers. Approximately two-thirds of the District is served by a separate sewer system, while the remaining one-third is served by combined sewers. A combined sewer system conveys both sanitary sewage and storm water in one piping system. The District's combined sewer system was developed before 1900. Separate systems are comprised of two independent piping systems: one system for "sanitary" sewage (i.e., sewage from homes and businesses) and one system for storm water. During normal, dry weather conditions: Sanitary wastes collected in the combined sewer system are diverted to Blue Plains at facilities called regulators or dams. Typically, there are no overflows to the District's rivers and creeks. During periods of rainfall, the capacity of a combined sewer may be exceeded. When this occurs, regulators are designed to let the excess flow, which is a mixture of stormwater and sanitary wastes, be discharged directly into the District's rivers and creeks. This excess flow is called combined sewer overflow or CSO. Release of this excess flow is necessary to prevent flooding in homes, basements, businesses, and streets. CSO's are discharged to the Anacostia River, Rock Creek, Potomac River or tributary waters at CSO outfalls during most moderate rain events. There are a total of 48 potentially active CSO outfalls listed in the existing National Pollutant Discharge Elimination System permit from the United States Environmental Protection Agency.

Access & Use Information

Public: This dataset is intended for public access and use. Non-Federal: This dataset is covered by different Terms of Use than Data.gov. License: Creative Commons Attribution

Downloads & Resources

Dates

Metadata Created Date April 30, 2024
Metadata Updated Date February 5, 2025

Metadata Source

Harvested from DC data

Additional Metadata

Resource Type Dataset
Metadata Created Date April 30, 2024
Metadata Updated Date February 5, 2025
Publisher Department of Energy and Environment
Maintainer
Identifier https://www.arcgis.com/home/item.html?id=b8e5fb96e36943f88bdcec7f6001e13c&sublayer=31
Data First Published 2015-02-27T20:55:51.000Z
Data Last Modified 2023-12-08T00:00:00.000Z
Category geospatial
Public Access Level public
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 1453ea6a-1a3f-4507-9145-2546f2427426
Harvest Source Id b05f955a-65d6-4288-9558-15a5ebc74e36
Harvest Source Title DC data
Homepage URL https://opendata.dc.gov/datasets/DCGIS::combined-sewer-outfall-sewer-shed
License https://creativecommons.org/licenses/by/4.0
Metadata Type geospatial
Old Spatial -77.0798,38.8567,-76.9723,38.9761
Source Datajson Identifier True
Source Hash aa91d8a997b6de484e4780864c41619d9e0943a2054ecf04794f16247a7f9941
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -77.0798, 38.8567, -77.0798, 38.9761, -76.9723, 38.9761, -76.9723, 38.8567, -77.0798, 38.8567}

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