The order was issued on Monday afternoon after tests showed coliform bacteria was found in the water system.
The village said is needs to have two consecutive tests 24 hours apart from one another showing no coliform to be able to lift the notice. To verify the theory, the village said they would send samples to a different lab to compare results.
The latest test results showed the bacteria was still present as of Wednesday at 3:40 p.m.
Village President Dan Dycus said things are looking up after some recent testing. The lab received a clean sample Thursday and needs just one more on Friday for Wonder Lake to be in the clear.
"Once we have that back... we've already talked to the IEPA and confirmed we can lift the boil order," Dycus said.
The village board held an emergency meeting on Wednesday night in McHenry County for those dealing with water issues.
"The unexpected presence of coliform bacteria...leads us to suspect the issue might be due to laboratory errors rather than water contamination" the village said on social media.
In the meantime, leaders have distributed cases of water to impacted homes.
The village said east side water systems are not affected, including Stonewater. Only the systems on the west side of the lake are affected, impacting about 1,400 homes
Some village employees have been hard at work passing out more than 600 cases of bottled water.
"I mean it's been a struggle. I know they're doing all they can, but it's been hard resident Toni Baartz said. "You have to stop and think about every little thing."
Residents have been going through it at home trying to deal with the boil order, but they're hoping relief is near.
"Terrible... the water is yellow... can't take a shower," a resident named Frank said. "Rings around the toilet from the yellow water... can't drink the water."
The Wednesday night meeting saw residents voicing their concerns as they gathered more information. Some residents reported not feeling well earlier in the week, worrying that they possibly drank contaminated water over the weekend.
"I came back from vacay Saturday night not knowing about this," Frank said. "There were no signs, so I was drinking the water for three days, filtered, but I didn't get sick yet."
The village is urging those people to check with their doctors while they investigate those reports. In the meantime, residents are staying patient.
"I mean they're working on it, so that's all they can do," resident Emilio Pacheco said.
People in Wonder Lake will have to wait until Friday with hopes that another test comes back clean. If all goes well, the boil order will then be lifted.
What is coliform bacteria?
Coliform bacteria are naturally present in the environment, according to the DuPage County Health Department.
However, the presence of the bacteria in water could suggest that potentially harmful fecal bacteria could be present.