a. That drag race in Grease filmed in a huge drainage culvert…where the heck is that filmed? b. Over the years, I noticed some other shows with scenes filmed here. (You can’t miss it.) Does anyone know what shows have a scene filmed there? c. Is this some popular teen hang-out in CA?
It’s the L.A. River. Definitely not a place you want to hang out. Not exactly the best part of town.
Btw, most of the Rydell High scenes were shot at Venice High School, my alma mater.
Yep. Ninja’d.
The Wikipedia article has a Filming Location section, with a picture from Grease.
All these California dopers, and a PA boy points out that it’s the LA River.
Has anyone mentioned that it’s the LA River?
Around here we call it “Rio Los Angeles.” 
Guessed the answer just by the thread title.
It’s also where the final climactic battle against the giant ants took place in Them!
It’s the concrete channel where the LA river would flow if there was such a thing as the LA River. It is mostly just an artificial drainage ditch for storm water run-off.
That whole race scene in “Grease” happens on the dry river bottom of this river.
A river that is a dry concrete basin for most of the year is not a river, at least to me.
That’s nice but the name for that mostly dry concrete basin is and has been for decades
“The LA River”. I’m sorry that you don’t like the name. It that’s what it’s called.
You can work on changing it if you want. When you’re done with that you can move on to Greenland.
It’s a perennial river, it’s just the fake floodplain that’s dry. Like most rivers
Many movies have been filmed there. The truck/motorcycle/minibike chase scene in Terminator 2 is a well-known example.
Also the closing credits of Buckaroo Banzai: The Adventures of Buckaroo Banzai Across the 8th Dimension - End Credits - YouTube
Exactly. There’s always water in the middle channel. The dry flats on the sides are there to contain floods. Catastrophic floods in the 1930’s were why the river was channelized in the first place.
There’s a major project underway to revert as much of the river as possible to a more a natural appearance while still providing flood control.
That is fine. If you want to believe that your little concrete sewer ditch is a river, please continue to delude yourself.
Somebody told me it was the LA River.
You can probably create a whole thread on movie scenes that were filmed in the LA river.
There was a helicopter chase scene between a militarized police copter and two regular police copters (the movie “Blue Thunder”).
A space shuttle landed there once. (“The Core”)
Any others?
Yes. People often take kayaking trips down sewer ditches.