Also, your history of the area is essentially correct. The western part of Riverside Park was a ballfield going back into the 1930s and was built on fill land. The excursion boat dock that Gistok remembers was built sometime in the '50s and shows in DTE aerial photos from that time. What's now the eastern portion of the park was mostly taken up by a large gas works from the mid-1800s to about 1960. I had an great-uncle who worked there for many years.

The gas works ran from Fort St. to the river [[bisected by W. Jefferson), and roughly from 24th St. over to the bridge. The bridge was actually built over part of the gas plant, and the railroad roundhouse next door to the east. The portion of the gas works south of Jefferson was where the coal was delivered by boat & train and stored and handled. Maps from the 1920s show coal storage and a large retort furnace there for the burning of coal.

With the rising availability of natural gas, and the breaking up of the coal/gas monopolies, coal gasification slipped out of use and the coal portion of the gas works was shut down. Most of the gas co. buildings south of Jefferson appear to be gone by the late '40s. But the area was still owned by Michigan Consolidated Gas and did not become park land until the entire gas works was closed and demolished in the early '60s.

Hard as it may be for some people to believe today, no thought whatsoever was given to things like ground contamination back then. The city was just happy to have the land for a park. As Detroitnerd says above, any number of Detroit parks were built on former industrial sites, as were entire neighborhoods. Hell, when I was a kid in the '60s many Detroit Public School playgrounds, including the one at my elementary school, were surfaced with slag left over from steel production, which was given to the Board of Ed at little or no cost.