Found it!
The Lost Streams of Los Angeles, courtesy LA Weekly.
This is a must-read for geography geeks (like me), and armchair historians in general.
After I first read this article, I started paying attention to the topography in my neighborhood (Westlake), and could see where development had covered the old streambeds leading to the natural basins of MacArthur and Lafayette parks.
The aforementioned Bimini Slough was an outlet for Silver Lake before it was developed as a proper "lake". According to
an old map posted in the Daily Mirror blog, it ran from there all the way down to 6th & Alexandria. The map depicted a proposed (circa 1917) greenbelt redevelopment project for Bimini Slough called "Silver Lake Parkway":
