OKLAHOMA CITY - The streetcar project in downtown OKC has been successful so fat, but officials say illegally parked cars are increasing wait times. 

Since its debut Friday, the streetcars have taken over 20,000 trips around the city. 

In that time streetcar drivers find themselves continuously blocked by vehicles parked in no parking zones or parked over white lines on the cement. 

Arrival times help narrow down when to expect your next streetcar. However, the wait time for streetcars has gone from six minutes, to much longer, all because of illegally parked vehicles throughout the city. 

"That does kind of stink because the car can't go through the car. But it makes it really difficult for people that are trying to make this transportation a lot easier and a lot better," said first time streetcar rider, Alan Miller. 

It's important to make sure you're following rules, parking within lines and staying out of no parking zones. 

EMBARK says problem areas include the Oklahoma City University law stop, the business district and Myriad Gardens. 

"If you're making a quick a quick delivery or letting someone of, if a train is behind you its going to hold up the entire system and slow it down," said Michael Scroggins, Public Information Officer for EMBARK.

If a train does end up stuck behind you, they've got a pleasant way of going about it. 

"They have a horn and it is a little larger than the one that you and I have in our cars. Its going to definitely make you uncomfortable and it is meant to. It's called an obstructionist horn and they're going to blow that until you move."

It's a minor issue to navigate, considering the scope of the project in a growing downtown. 

"For years we've probbaly taken those (no parking spots) for granted and just made quick trips and deliveries," said Scroggins. "Just be mindful that this is not going to hold up. Potentially, if we had all five vehicles out there, that's over 500 people you could be holding up as well as possibly other motorists."