Outfall

---

title: "Outfall" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["sewerage-infrastructure", "water-pollution"] description: "Discharge point of a drain or waste stream into a body of water" topic_path: "general/sewerage-infrastructure" source: "https://en.wikipedia.org/wiki/Outfall" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Discharge point of a drain or waste stream into a body of water ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/c/ce/Bell_Wharf_CSO_outfall_in_London.jpg" caption="Outfall with a flap valve at [[River Thames]] in London"] ::

An outfall is the discharge point of a storm drain or waste stream into a body of water. In the United Kingdom, the term may also apply to discharges from a "watercourse", which may be a river, stream or canal.

United States permit requirements

::figure[src="https://upload.wikimedia.org/wikipedia/commons/c/c9/FlorhamParkSewerageUtilityOutfall.webm" caption="Outfall from a sewage plant discharging to [[Passaic River]] in New Jersey"] ::

In the United States, point sources may not discharge pollutants to surface waters without a permit issued through the National Pollutant Discharge Elimination System (NPDES), as required by the Clean Water Act. Most NPDES permits are issued by state environmental agencies. The U.S. Environmental Protection Agency (EPA) issues permits in some locations.

Point sources include industrial facilities; service industries; municipal governments (particularly sewage treatment plants and stormwater outfalls); other government facilities such as military bases; and some agricultural facilities, such as animal feedlots.

References

References

1. (2025-04-06). "Structure: Outfall". United Kingdom Department for Environment Food & Rural Affairs.
2. United States. {{USPL. 92. 500. Federal Water Pollution Control Act Amendments of 1972 Approved October 18, 1972.
3. (2025-06-03). "National Pollutant Discharge Elimination System". U.S. Environmental Protection Agency (EPA).
4. (2025-06-03). "NPDES Permit Basics". EPA.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::