Explained: What’s going on with fluorescent green water in this Houston bayou

HOUSTON – Residents near Willow Bayou wondered about a bright green liquid at Willow Bayou. The big question -- what was it?

The brightly colored water could be seen as far as the eye could see.

“Even for me who is colorblind, I can tell that that’s green,” said Bob Pennington, a neighbor.

The Willow Bayou is Pennington's backyard. He has lived in his neighborhood for 20 or so years.

"We have seen a lot come through," Pennington said.

However, for this Memorial Day, Tax Day and Harvey flood survivor -- this is a first.

“We have not seen the green sludge,” Pennington said.

Other neighbors noticed too.

"I just heard there was green stuff that was in there," Carl Rose, another neighbor said.

Pennington thought it could have been paint.

“I would definitely be concerned, we got kids around here. We got grandkids that come and visit and so anything like that we’d be concerned about,” Pennington said.

Other neighbors did some investigating. Rose was not concerned but was definitely curious.

"It didn't put out any smell, so we just waited to see what it was," Rose said.

The city of Houston released the following written statement:

"Houston Water performed dye testing after a cave-in underneath a sidewalk on the 11900 block of Hillcroft. Testing helped Houston Water determine damage was only to the stormwater line and will be repaired. The dye is biodegradable and the color will fade over the next few days. This testing will NOT impact drinking water in the area.

“For concerns over water color, please call 311 (713.837.0311) or email 311@houstontx.gov.”

For some neighbors, it was a relief.

“That always makes me happy because the environment is important to me,” Pennington said.