“They just wanted to be able to use it,” Mr. Belt said.

The garbage containers, which he described as “newish,” were cleaned and lined in plastic, and a filtration system was installed, as on a regular above-ground pool. Mr. Belt’s wife, Antonia, stitched together the coverings for the cabanas; the furniture came from Ikea. The main cost was the wood for the deck and the water: about 18,000 gallons, delivered from a New Jersey aquifer for $1,200.

“I tried to do it so that even if you had to rent one, you could do a stand-alone Dumpster, a grill and chair for under $1,000,” Mr. Belt said. Copycats are welcome, because Macro-Sea itself is using the project as a template for a larger idea: turning eyesore strip malls into artsy community destinations, with Dumpster pools and other indie attractions.

“I thought if we could get people to come here and swim in a Dumpster, I could probably use the same aesthetic sensibility” to get people  and, not incidentally, better retailers  to come to a dingy strip mall, Mr. Belt said. The company hopes to open its first repurposed shopping center in Atlanta this fall, ideally with dozens of pools in the parking lot that visitors can rent for the day.

While the project is conceptually simple  get a bunch of trash containers, clean and seal them, fill with water, jump in  there were a lot of details to finesse. The coarse edges inside the containers were filed down, and underneath the liners, the bottoms were covered in sand, for soft landings. Tightly packed sandbags double as benches along the walls, and pool toys and kid-friendliness provide an intentional counterpoint to the neighborhood grit.