#TBT: What can Old Photos Tell Us About Water Quality?
Per Tuesday’s post about the State of the River Report, the Minneapolis Star Tribune river series and other “water in the news” these days, it seemed opportune to try to see if certain kinds of historical data/records convey information similar to what we are now hearing about in these accounts. Can photographs from the past show us river conditions?
The answer is, yes, but only in limited ways. Obviously, all we have is what people decided to photograph and what (other) people decided to put in archives. So we have images from particular events like floods more than pictures of more everyday scenes. The whole question is worth a closer, more systematic look (Honors thesis, anyone?) but here are two brief examples:
This image from the Mississippi River flood of 1943 in Minneapolis shows water encroaching on a residential area. It’s reasonable to surmise the sorts of loose materials, garbage, and other detritus that the floodwaters will carry from place to place. Whatever is in the drum in the foreground may be leaking. Further research would be necessary to determine if this particular location had stormwater and sanitary sewer connections or if human and animal waste just went straight to the river. Regional sewage treatment had begun by this point, and further research would be able to determine what the particular treatment entailed.
Another flood image, this time of a Minneapolis lumberyard. Loose material is evident in the picture’s center and the ground plane is undoubtedly a mix of sawdust, mud, and other materials. Accounts from the 19th century indicate that at times the river was so full of sawdust that steamboats grounded where the sawdust and scraps had piled up on the river bed; this 1938 photograph was made after the federal 9 foot channel project had been implemented so it’s unlikely that there was THAT much lumberyard trash in the river!
Seventy years from now, in 2085 or so, what will images from today show about the modern Mississippi River, and how will those images support arguments about water quality that are contained in news accounts and “State of the River’ reports?