Crews are in the process of cleaning up mounds of trash in an East McKinney creek bed.
The trash has been building up in Wilson Creek just south of Industrial Boulevard in east McKinney.
The garbage extends for about a football field in length along the creek and is coming from upstream, officials say.
Water bottles and floatable toys make up much of the mess.
City crews found the mess a couple weeks ago and have been cleaning up ever since.
"The first time I saw it I just couldn't believe it, because you wouldn't think trash could accumulate quite like that, but it did," said Joseph Daley, stormwater administrator for the city of McKinney.
Wilson Creek drains into Lavon Lake, a source of drinking water in North Texas.
Daley says the city will continue to monitor the area but expects the problem to persist as long as people continue to litter.
He encourages people to be more mindful of where the trash they leave behind ends up.