Apparently, back in the 1930s, they rerouted the Grand River so people could go pick up rocks. Why? Let's find out.

I stumbled upon this photo of some citizens from our fair city picking up rocks from the bottom of the Grand River.

It comes to me via the wonderful Grand Rapids City Archives Instagram feed, which is a treasure trove of old school GR stuff, and a site I highly recommend. (I especially love the old mug shot photos).

This photo is from August of 1931 when they temporarily rerouted the river to allow city workers to collect big rocks to shore up the sides of the river. I would imagine they were having some erosion problems.

Several keen observers have identified the bridge in the background as the Michigan Street bridge, and the big factory in the background as the original Bissell plant.

Can you imagine if they rerouted river like this today what they might find?

Several of those damn SPIN scooters, I'm sure of it.

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