Word or phrase meaning a target for outflow / place to put something in excess

Question

Is there a word or phrase meaning a target for outflow or a place to put something, when there's too much of something and it has to go somewhere?

Like a detention basin but in more general use, since that is a very specialized thing used for outflow of water.

The words drain or sink are in the ballpark, but they seem to have the wrong connotations; I'm looking for something that sounds a bit less like a plumbing term.

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(edit: in my specific instance I'm working in the subject of energy flow rather than liquid flow, but I'm interested in a general answer)

Answer 1

Overflow has been repurposed for more general usage to refer to places to place excess people or items. While the entry in Merriam-Webster primarily lists its liquid meanings, like

3 : an outlet or receptacle for surplus liquid,

I've seen many times transferred meanings to contexts like event rooms and inventories.

For instance, an overflow room is where event attendees are placed if they cannot fit within the main venue. Often these rooms have an audiovisual feed of the main event. Examples:

Another Easter, another trip to the overflow room at church. What’s the overflow room at church? It’s the room you are herded into when you don’t get there early enough to sit in the main sanctuary with the rest of the saints. Some churches, like mine, have several. ("Church Overflow Rooms: Do You Hate Them or Nah?" The Root, 2 April 2018.)

Displaying a stream in an overflow room ... To set up streaming in an overflow room before an event: (University of Cambridge, Faculty of Mathematics, Computing instructions)

Overflow can also be applied to other collocations, like room blocks, dorms, and warehouses:

Overflow room block avaliable [sic]. We’re happy to announce a new block of rooms at a nearby hotel for the 2016 Annual Meeting. (National Council on Public History)

Likewise, Saurabh Desai, a Boston University freshman, says he has felt neglected by his university. Mr. Desai wanted a residence hall close to the center of campus, but instead found himself in an overflow dorm 15 minutes away at Emmanuel College, a school for women. ("At Many Colleges, Dorm Living Is Easy - Though Crowded." CS Monitor, 3 Nov. 1998. )

How To Manage Warehouse Overflow ... Properly managing inventory is a common challenge but dealing with an overflowing warehouse doesn’t have to be an ongoing issue for your organization. Below are some of the common warehouse overflow problems that companies face and proven warehousing overflow solutions to help when you have too much stuff and not enough room to store it. (NewStream)

Answer 2

I hadn't thought of it yesterday when I asked, but outlet might be another word. (Still has strong connotations with pipes and water, though.)

out·let (out′lĕt′, -lĭt) n.

1. a. A passage for escape or exit; a vent. b. A means of release or gratification, as for energies, drives, or desires: exercised as an outlet for frustration.

2. a. A stream that flows out of a lake or pond. b. The point where a stream flows out of a lake or pond. c. The mouth of a river where it flows into a larger body of water. d. The point of intersection of a driveway and a road, especially in a rural area.

3. a. A commercial market for goods or services. b. A store that sells the goods of a particular manufacturer or wholesaler.

4. A receptacle, especially one mounted in a wall, that is connected to a power supply and equipped with a socket for a plug.